THE CARLSBERG FOUNDATION’S OCEANOGRAPHICAL EXPEDITION ROUND THE WORLD 1928-30 AND PREVIOUS “DANA”-EXPEDITIONS UNDER THE LEADERSHIP OF THE LATE PROFESSOR JOHANNES SCHMIDT

OANA-BEPORT No. 74

THE SYSTEMATICS AND BIOLOGY OF THE FAMILY PHRONIMIDAE (CRUSTACEA: AMPHIPODA)

BY GHANG-TAI SHIH MARINE SCIENCES CENTRE, McGILL UNIVERSITY

WITH 22 FIGURES IN THE TEXT

PUBLISHED BY THE CARLSBERG FOUNDATION

THIS PAPER MAY BE REFERRED TO AS: •DANA-REPORT No. 74,1969«

COPENHAGEN ANDR. FRED. HOST & S0N

PRINTED BY B1A.NG0 LUNO A/S CONTENTS Page Pnge In tro d u c tio n ...... 3 III Life h is to ry ...... 33 Acknowledgements...... 4 Development and growth ...... 33 5 P rehatching...... 34 H istory...... 5 Juvenile p erio d ...... 34 Terminology...... 7 Im m ature period...... 36 Key to the genera and species Adolescent period...... 37 of the family Phronimidae .... 8 Mature period ...... 37 Familv Phronimidae D a n a ...... 9 Propagation...... 41 Genus Phronima (L.\treille) ...... 10 Time of sexual maturation...... 42 Phronima sedenlaria (F orskal) ...... 10 Breeding seasons...... 42 Phronima allanlica Gu e r in ...... 14 Number of broods per individual.. 46 Phronimo. solitarici G u e r i v ...... 16 Food habits...... 47 Phronima pacifica St r e e t s...... 18 Relationship to the other animals, ...... 48 Phronima colletti B ovallius...... 21 IV Distribution...... 49 Phronima affinis Vosseler...... 25 Vertical distribution...... 49 Phronima curvipes Vo sse l e r ...... 26 Geographical distribution...... Phronima stebbingi Vosseler...... 29 Zoogeography...... 62 Genus Phronimella Cl.

•\ thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy. Author’s address: Canadian Oceanographic Identification Centre (COIC), Museum of Natural Sciences, Ottawa, Ontario, Canada. I. INTRODUCTION

his is the first attempt to study the circUinglobal pelagic planktons of the t’amily Phronimidae follected Tfrom all oceans. Before V ossel f.r (1901) published his work on the systematics of the phronimid species, the sexual dimorphism and the age variation in these animals proved confusing to the taxonomists. Synonyms of the species were mostly made at this period. Based on the collections made by the German Plankton Kxpedi- tion from the waters of the X. and S. Atlantic Oceans, V o s s e l e r reviewed the whole family and his ]:irescn- tation has since then been recognized as the most valuable reference for it. In the first three decades of the present century, attracted by the successful collection of the Challanger Expedition, many oceanographic expeditions have been sponsored by various countries, and through the collections of some of these expeditions, phronimid amphipods have been recorded from a wide range of localities. Most of these reports, e.g., B arnard

(1930, 1932, 1937 a & b), C h ev r eu x (1900, 1913, 1935), M ock (1926, 1927 a & b), P ir l o t (1929, 1930), S pandl (1924 a & b) and S t e p h e .v s e .v (1923, 1924), mainly dealt with the systematics. Little or no attention has been given to the other biological studies of these animals. The knowledge of this family has therefore not been improved very much since V o s s e l e r . The lack of definite discovery of the males of some species remains a problem. The distribution of the animals was frequently said to be cosmopolitan. This generalized statement for the distribution was strongly criticized by Hi rlev (1960 b), who rightly pointed out that, “an analysis of the information already available in the literature would show that many of these species are not truly cosmopolitan at all, but restricted to definite water masses with definable physical properties, recognised by hydrologists.” The purpose of the present study is multiple. The systematics of the Phronimidae is revised in an attempt to evaluate all the species that have so far been described. The general life history of the animals was studied, with emphasis on the postnatal development and the manner of propagation. These are practically unknown among the hyperiid amphipods. Although the result may be inaccurate in detail, because of the nature of the material available, the general pattern of the process no doubt will be reliable. The distribution pattern in relation to the oceanic environment is discussed. The factors which affect the distribution and the man­ ner in which the animals speciate are speculated on from the present material as well as from the literature on the prevailing theories. The material available for the present investigation comes from various sources listed below. Numeric­ ally and geographically it exceeds any of the previous works on this family:

1. Dana Expedition 1920-1922; Atlantic and Gulf of Panama. 2. Dana Expedition 1928-1930; around the world. 3. California Cooperative Oceanic Fisheries Investigation (CCOPT), cruises 1, o, 9, and 20; eastern N. Pacific olT California coast (Anonymous, 1951).

4. Longlining stations; eastern equatorial Pacific (W il s o .n and S h i.mada, 1955). 5. Bellairs Research Institute of McGill University; waters off west coast of Barbados, West Indies (Lewis et al., 1962).

6 . Zoological Museum of the University of Copenhagen; collections deposited at the Museum from various waters, including the male specimens of the so-called “Phronima collelti” taken from the Mediter- rancan hv the Danish Occanographic Expedition (Thor) and identified b y S t e p h e n s e n (1924), and the phroniniids collccted b y the Galathea (Bri i \, 1957 a). Two months of field work was vindertaken at Barbados in an attempt to rear the phronimids in the aquarium. Since the phronimids occvir only rarely in this area, the experiment was greatly hampered and was not successful.

AC KNOWLE D G E M E NTS

The author wishes to thank Dr. M. J. Dlnb.\r, his academic supervisor, who introduced the present problem to the author and has offered valuable suggestions and critici.sms during the course of the study. Gratitude is due to Dr. I. A. M cL ahkn of the Marine Sciences Centre, McGill University, who has read and made worthwhile comments of the manuscript. Dr. J. B. L e w is , Director of the Bellairs Research Institute at Barbados, West Indies, is acknowledged for his help in arranging facilities for field work and for his kind­ ness in allowing the author to utilize the collection deposited at the Institute. The author is grateful to the Carlsberg Foundation of Denmark which has allowed him to use the valuable collection taken by the "Dana”. Many thanks are due to Dr. T. W o l f f of the Universitet Zoologiske Museum, (Copenhagen, who has sent him the phronimid collection of the Museum. His sincere thanks arc extended to Dr. T. M B o w m a n (^f the Smithsonian Institution, U. S. National Museum for providing working space at the Museum and permission to examine collections from the eastern Pacific Ocean. The author wishes to express his appreciation to Dr. E. L. B o v s f i f l d of the National Museum of Canada for allowing the exami­ nation of pertinent collections of the Museum.

Mrs. D. C. M a c l k l i .a n of the Marine Sciences Centre, McGill University, has helped the author in many ways, especially in polishing the English of the manuscript and in proof-reading. To her the author wishes to ex])ress his warmest appreciation. The author is greatly indebted to his wife who has assisted him in the preparation of the drawings and the editing of the station list. Finally the author would like to thank the National Research Council of Canada which has financially supported the present investigation. This paper is dedicated to my Mother. II. SYSTEMATIGS History

The members of the Family Phronimidae have been recorded as early as in the last quarter of the eighteenth century. The commonest species, Phronima sedentario, was named by F orskal (1775) as Cancer sedentarius. Well known even among the early carcinologists, it has been however allocated to dirferent families by various authors, e.g., Crevettines or Gammarinae (L atreillf., 1802, 1806; Risso, 1816), Gamarini (L each, 1813), Uroptera (L atreille, 1829), and Hyperines (L ucas, 1840). L each (1813-1814), not seeing a specimen of this species himself, was the first person to consider that the genus Phronima L atre­ ille probably forms a distinctive family. Not until the middle of the nineteenth century was the name of Phronimidae established. Although the authority for naming the Phronimidae is credited to Dana (1852), nevertheless W hite (1850) proposed the name two years earher. In W hite’s Phronimidae, there are two genera, Hyperia Latreille and Phronima. However no definition of the family was given by him. D ana (1852) instituted Phronimidae as one of the three families under his “Subtribus Hyperidea” and gave the following definition for the newly founded family: “Antennae 2dae exserte. Abdomen in ventrum se non flectens. Pedes 5ti 6tive sive crassi sive elongati, saepius prehensiles, quoque 3tii 4tique saepe prehensiles.”

The Phronimidae, according to Dana, were divided into three subfamihes, containing six genera: Subfamily 1. Phroniminae, Phronima L atreille and Primno Gu e r in ; Subfamily 2. Phrosininae, Anchylomera E dward, Phrosina Risso and Themisto G u e r in ; Subfamily 3. Phorcinae, Phorcus E dward. Judging from the position of the antennae and the morphology of the fifth pair of peraeopods'. B ate (1862) rejected the genus Phorcus from the Phronimidae and made it an independent family, Phorcidae. In the meantime he dropped the genus Themisto from the subfamily Phrosininae and put it under the family Hyperiidae. He also shifted the genus Primno from the subfamily Phroniminae to the subfamily Phrosininae based on the common characteristic of possessing foliaceous uropods. In 1871, C laus assigned his former Phronima elongata Claus (1862) to a new genus, Phronimella. In the second edition of his “Grundziige der Zoologie”, Claus (1872 b) rearranged the family Phronimidae. He abandoned the rank of subfamilies and referred the genus Anchylomera to the family Hyperiidae. The Phronimidae, by his classification, consisted of four genera: Phronima, Phronimella, Dactylocera L atreille (= Phrosina) and Primno. Streets (1877) created a new genus, Anchylonyx, for his new species, A. hamatiis. He found that Anchy- lonyx, by having a similar shape of the head, peraeon and pleon, the grouping of eye facets into two, and the peraeopods (except peraeopod 5), is very closely allied to Phronima and that spinous peraeopod 5 is common to both Anchylonyx and Primno; he considered that the two genera, Phronima and Primno, are linked by Anchylonyx, and therefore believed that the position which Dana assigned to them was the cor­ rect one. A. hamatus, however, was proved to be the synonym of Claus’ Phronimella elongata (S t r eets, 1882).

* According to B a t e ’s nomenclature, this is the third pair of peraeopods. For the discussion of n a m in g the peraeopods, see p. 8. Ci-.u s (1879) agreed with B a t e (1862) in excluding the Phorcinae and retained two subfamilies, Phroni- minac and Phrosininae, in D a n a ’s Phroniniidae. Two new genera, Phronimopsis and Paraplironima, were ercated and introduced to the Phroniminae by him. Gi'HSrAKC'.KKR (1886) made an addition to C lals’ Phroniniidae. Without giving any reason, he removed

the genus Tryphmm I?okck from Hokck’s family Tryphanidae stating that it probably belonged to the family Phroniniidae. He assigned it to neither of the two subfamilies. The greatest alteration of the family Phroniniidae is found in the laborious work of R o v a l l i u s (1887). He fountled a new family, Anchylomeridae, for the subfamily Phrosininae and removed Phronimopsis and Paraphroniina from the subfamily Phroniminae. Paraplironima formed his new family, Paraphronimidae, and Phronimopsis becamc one of the nine genera in the Hyperiidae. To the remainder of the Phroniniidae, he added the subfamily Dairellinae, based upon the new genus Dairella B o v a l l i v s (1887), to form the family I'hronimidae. .Since this family had been so largely changed, he gave the following diagnosis;

•'Head large, luiniil, more or less conical, much deeper than the body, lives large, occupying parts of the sides and the (op of the head. First pair of antennae Fixed at the anterior side of the head; with a rnulH-arficiilate flagelluiii in the male): second pair fixed at the anterior side of ttie head, multi-articulate (in the male) or rudimentary (in the female). >hindlbles without palp. Seventh pair of peraeopoda not transformed. Peduncle normal.”

Bovali.u s retained Dairellinae as a subfamily of Phroniniidae on the basis of a few similar characteri­ stics, namely, the morphology of the first pair of antennae, the absence of the second pair of antennae in the female, the form of the mouth-parts and the fusion of the epimerals with the peraeon segments. But, “further anatomical studies of Dairella and Phronima will make it desirable to place Dairellinae as an independent family . . .” (Bov^lliis, 1889). From collections made by the “Challenger”, S tk b b i.v g (1888) added many species to the family Phroni- midae. Even though most of these new species were found to be only synonyms of known species, the biblio- grajjhy which he compiled is the most complete one up to that date. The present status of the family Phroniniidae was introduced by V o s s e l e r (1901), based on the material collected by the German Plankton Expedition. \ ’o s s e i . k r excluded Dairellinae from Phronimidae and made it an independent family, Dairellidae. The points on which these two families do not agree, according to V o s s e l e r , are great enough to justify their separation. However, due to the structure and form of the first antenna, the reduction of the second antenna in the female, and the characteristics of the mouthparts, V o s s e l e r considered them to be closely related. The characters separating these two families are tabulated below: Phronimidae Dairellidae 1. Head conical. 1. Head globular. 2. Antenna 1 with one-jointed peduncle in the female. 2. Antenna 1 with three-jointed peduncle in the female. 3. The first two peraeon segments free or partly fused, 3. The first two peraeoon segments coalesced, not higher higher than the following segments. than the following segments. 4. Peraeopod 5 more or less modified to form a prehen- 4. Peraeopod 5 not specially modified, sile organ.

More specimens of the family Phronimidae have been collected since the German Plankton Expedition. Many o f them have been worked out. In general, V ossei.er’s contribution seems to be the most reliable reference available in the literature. Only a few minor questions, such as the lack of knowledge of either the male or female of certain species, have been raised by later authors. As mentioned before, F o r s k . \ l found Cancer sedentarius in 1775. More than a quarter of a century later, L a t r e i l l e (1802) had established a new genus, Phronima, for F o r s k a l ’s species. The genus was defined by L a t r e i l l e as follows:

“Antennes apparentes au nombre de deux, presque setac6s, de trois articles. Des palpes sailans, setaces. Dix pattes; les quartre anterieures et les quartre posterieures terminees par une piece conique, un peu arquee; celles de la troisieme paire les plus anneaux etroits; plusierus styles alonges, articul^s et bifides, a I’exlreinit^ du corps.” Risso (1816) described a new species, Phroiiima ciistos, from the Mediterranean. Although this species has been quoted and found later by other carcinologists, it was declared by C osta (18o3) to be identical with F o r sk a l’s species. The first male specimen of Phronimd was discovered by Cocco (18;J2). He gave a new genus to contain this specimen and named it Bivonia znnznrn. The fact that B. zanzara might be a male of the genus Phrouimn was pointed out by Di-; X atalk (18.')0, quoted by S tkbbing, 1888). Cocco’s new species was listed as a syno­ nym of P. sedentaria by B ovallu s (1889). However, judging from the original figure by Cocc.o, it is hard to tell to which species it belongs, but due to the presence of the well-developed second antenna, it is not

P. sedenlarin. Dk X atalk also named a male specimen of this genus as P. coccoi. This again, according to STEBiiiNG (1888) was impossible to identify as such, even if he had had his specimen. Two new species, P. ntlantica and P. solitnria, were described by (in';iu.\ (183(ia, IH.'Jdb). The latter was considered to be a variety of P. atUmHcn by \'ossi;i-r.K (H)Ol). Although P. ntlantica was accepted as a genuine species, it was at once susjiected by Mii.nf.-Edwauds (1838) to be the yoimg form of P. scdcntaria. Bate (1862) tentatively described a new species, P. hnrm-ensis, from Borneo, but suggested that this new species might only be a synonym P. sedentnria. More svnonyms of the latter were found in the literature of the late nineteenth century, e.g., P. novae-zenlandiae P o w e l l (187.5), P. spinosa B ovai.l u s (1887) and

P. tenella S tebbixg (1888). Two new species were added to the,genus Phronima, before the end of the last century: P. pacifn-a S t r e e t s (1877) and P. colletti B o v a ll u s (1887). S tebblvg (1888) recorded P. pacifna and established a new species, P. niegalodoiis, from the Challenger’s material. The latter, however, is the synonym of P. atlantica V. solitaria, the former is later to be P. stebbingi, one of the three new species of Phronima described by

VossELER (1901). The other two species are P. curvipes and P. affmis. D udlich (1926) added the last new species, P. gnsti to this genus. Due to the considerable morphological differences existing between the females and males of the same species in the genus Phronima, there has been a great deal of confusion in the systematic work of this group of hyperiids. For instance. Cm \ (189,')) insisted that the second antenna in the male of P. sedentaria is vestigial in the young and becomes well developed in the adult. He assigned the mature male of P. atlantica to the adult stage of P. sedentaria. The male of the true P. sedentaria hence became the young form. Of the known species of Phronima, only four have both the female and male recorded, i.e., P. atlantica, P. colletti, P. sedentaria and P. stebbingi. In other species either the female only (P. cnrnipes, P. pacifica, and the variety P. atlantica v. solitarin) or the male only (P. affmis and P. gasti) are known. C l a is (1862) described a new species, Phronima elongatn, which subsequently became the type species of the new genus, Phronimella C laus (1871). Since C laus gave only a short diagnosis in his Grundziige der Zoologie (C laus 1872), his description for the type species might be an alternate for this purpose. He stated; “Korper sctilank und zart. Das Abdomen sehr langgestreckt niit 3 Setiwiinmfusspaaren und 2 Paaren von Spring- fiissen versetien. Thoracalfussen selir diinn und schwacti, die dritten und nocti niehr die vierten fast geisselfonnig verlangert, die fiinften sind nicht Sctieeren sondern Klauenfiisse.”

However, a correction should be made in this statement since the third thoracic foot is longer than the fourth and, in the male, the second uropod is present, though much smaller than the others. 'J'here is only one species know n in the genus Phronimella. Several synonyms are found in the literature, e.g., Anchylonyx hamntus St r e e t s (1877), Phronimella filiformis B ovallius (1887) and P. hippocephala G iles (1887).

Terminology

The Head: The sessile eyes are enormously large. Each eye consists of two sets of facets: the superior group, located on the dorsal and the upper lateral side of the head; the inferior group, on the lower lateral side. There are two pairs of antennae, the first or .superior antennae and the second or inferior antennae. The antennae are composed of two parts, the basal (peduncle) and the distal (Ihigelhim). The niouthparts contain five parts, the mandible, lower Up, first and second maxillae, and maxilliped. The inner margin of the mandible bears the culling edge at the distal end and has a molar process proximally. The lower lip has a well developed lateral lobe and a median incision. The first maxilla has a one-jointed palp and an outer plate; its inner plate is lost. The second maxilla possesses inner and outer plates. The maxilliped lacks a palp. Its inner plates fuse medially to form a medial lobe; the two outer plates remain free (for a comparative account

of the maxilliped of the Hyperiidae, see P ir l o t , 1932). The Peraeon or mesosome consists of seven peraeon segments. Each segment bears a pair of appendages, the poraeopods. A’ery frequently, especially in the old literature, the first two pairs of peraeopods are called gnathopods, their function difl'ering from the remainder which accordingly are named the first to fifth peraeo­

pods. This nomenclature however has resulted in great confusion. For instance, S ars (1895) referred to the first two pairs as gnathopods in his text and as peraeopods 1 and 2 in his plates. It also produces confusion in that it is necessary to give difTerent numbers to the appendages and to the segment that belongs to the same unit., e.g., peraeopod 2 of the peraeon segment 4. To avoid such confusion and to keep the append­

ages consistent with their body segments, it is reasonable to follow S p o o n e r (1947) who named them as peraeopods 1 to 7. Each peraeopod is seven-jointed; starting from the proximal one, they are; coxus, basos, ischium, merus, carpus, metacarpus and dactijlos. The coxus is indistinct in this family. The basos is the longest joint. The ischium and merus are short. In peraeopod 5, the carpus is very well developed and with the metacarpus forms a perfect subcheliform or an imperfect folding hand. The dactylos is minute, spine-like.

There are three pairs of branchial pouches, each attaching posteriorly to peraeopods 4 to 6 . In the adult females there are four pairs of brood lamellae or oostegites, located medially to peraeopods 2 to 5. The carpus of ]ieraeopod 5, or carpus 5, is one of the structures which provides the most obvius specific characteristic in this family. The anterior distal part of the carpus ends in a pointed protrusion, the carpal process. The projection on the lower or ventral margin of the carpus is termed the carpal tubercle, and possesses several tooth-like projections. The carpal tubercle may or may not have a separate anterior tooth. If the latter is present, then the carpal tubercle is said to be bifid; otherwise, it is called single. The projection on the upper or inner edge of the metacarpus is likewise termed the metacarpal tubercle. The Pleon or metasome consists of three pleon segments. Each bears a pair of pleopods consisting of an unsegmented basal peduncle and two multiarticulate rami, the outer exopodite and the inner endopodite. The I'rus or urosome: There are three urus segments, each bearing a pair of uropods. The uropod has a styliform peduncle and two rami. The first urus segment is free; the second and third are coalesced and are usually termed the coalesced segments. The Telson is small and rounded posteriorly.

St e i.nberg and D o ugherty (1957), working on caprellids, have modified certain spellings. They suggested using “pereon” and “pereopod”, and “pereod” and “pleod” instead of “peraeon” and “peraeopod”, and “peraeon segment” and “pleon segment”. Y ang (1960) and B owman (1960) have applied these terms in hyperiids, but since these terms are otherwise not widely adopted in the literature, it seems wise to follow the conventional terms to avoid confusion. In the description of the species of this family, several measurements or ratios are of specific value. The abbreviations with their meanings are as follows;

Hjj Height of head in first peraeon segments Hi Length of head in first peraeon segments P/A Length ratio of pleon plus urus, including the uropods, to head plus peraeon Pli/Per, Length ratio of pleon segment 1 to peraeon segment 7.

Key to the Genera and Species of the Family Phronimidae The following key is modified from Shui and Dlnbau (1963); it applies to the adults only; 1. Body very slender; peraeon segments 1 and 2 partially coalesced; carpus of peraeopod 5 slender, with several strong spines at anterior edge, and forming together with tlie metacarpus an imperfect folding hand; uropod 2 wanting in female and rudimentray in m ale...... Phronimclla Claus P. elongala Claus Body elongate; peraeon segments 1 and 2 not coalesced, carpus of peraeopoa 5 more or less dilated, with a strong carpal process and forming together with the metacarpus a strong perfect subcheliform hand; uropod 2 well devel­ oped in both sexes...... Phronima Latreille 2 2. Male...... 3 F em ale...... 9 3. Antenna 2 rudimentary...... 4 Antenna 2 well developed...... 5 4. Peraeopods 1 and 2 with a strong posterior process at the distal end of the carpus; peraeopod 5, a separate tooth in front of the carpal tubercle...... P. scdenlaria (ForskAl) Peraeopods 1 and 2 without process at the distal end of the carpus; peraeopod 5, without separate tooth in front of the carpal tubercle ...... P. affinis V osseler 5. Peraeon shorter than pleon; 7th peraeon segment shorter than 1st pleon segment...... P. slebbingi V osseler Peraeon longer than pleon; 7th peraeon segment longer than or equal to 1st pleon segm ent...... 6 6. Peraeopod 5, merus and carpus longer than w ide...... 7 Peraeopod 5, merus and carpus wider than long...... 8 7. Peraeopod 5, metacarpus apparently protruded beyond the anterior margin of the carpus; except the anterior separate tooth, all processes of the carpal tubercle close together...... P. allanlica Guerin Peraeopod 5, metacarpus not, or only slightly, protruded beyond the anterior margin of the carpus; in addition to the anterior separate tooth, the first process of the carpal tubercle slightly apart from the remainder P. colelli B ovallius 8. Peraeopod 5, except the anterior separate tooth, all processes of the carpal tubercle close together; inner ramus of uropod 2 at least one-third shorter than the outer ram u s...... P. curvipes V osseler Peraeopod 5, in addition to the anterior separate tooth, processes of the carpal tubercle spacely arranged; inner ramus of uropod 2 subequal to or at least longer than two-thirds of the outer ra m u s...... P. pacifica S tre ets 9. 1st pleon segment longer than 7th peraeon segm ent...... P. slebbingi V osseler 1st pleon segment shorter than 7th peraeon segment...... 10 10. Peraeopod 5, basos strongly curved in a reversed “ S” ...... P. curvipes V osseler Peraeopod 5, basos more or less straight...... 11 11. Peraeopod 3 longer than peraeopod 5 ...... 12 Peraeopod 3 shorter than peraeopod 5 ...... 13 12. Peraeopod 5, merus longer than wide...... P.collelli B ovallius Peraeopod 5, merus wider than long...... P. pacifica S tre e ts 13. Peraeopod 5, carpal tubercle bifid and weak, metacarpal tubercle indistinct...... P. allanlica G uerix Peraeopod 5, carpal tubercle single, metacarpal tubercle more or less developed...... 14 14. Peraeopod 5, carpal process slightly stronger or as strong as the carpal tubercle; metacarpal tubercle weak P. solilaria G uerin Peraeopod 5, carpal process extremely produced downward, carpal tubercle moderate, metacarpal tubercle very distinct...... P. sedenlaria (Forskal)

Family Phronimidae Dana

Phronimidae. D a n a , 1852: 315 (diagnosis; includes Primno, Anchylomera, Phrosina, Themislo and Phorcus). B a te , 1862: 316ff. (after D a n a but excludes Phorcus and Themislo). C la u s , 1872b; 467 (revision; contains Phrosina and Primno in addition to Phronima and new genus, Phronimclla); 1879: 59ff. (partly after B a te , 1862 and C la u s , 1872b, with the addition of Phronimopsis and Paraphronima). Gerstaecker, 1886: 487ff. (after C la u s , 1879, with the addition of Tryphana). Bovallius, 1887: 24f. (revision; retains only Phronima and Phronimclla with an addition of Dairclla). V o s s e le r , 1901: Iff. (revision; excludes Dairclla).

D iagnosis (after V o ssk i.e r (1901) and C h e v h e l x and F age (1925) with modification): Head large, conical and tapering ventrally, much higher than long; eyes very well developed, facets covering dorsal and lateral surfaces of the head; first antenna 2 joints in the female, with flagellum in addition to 3-jointed peduncle in the male; second antenna obsolete in the female, rudimentary or well developed in the male, if well developed, in addition lo the 3-jointed peduncle, with a many-jointed, slender flagellum; mandible without palp; coxus indistinct; peraeon lower than head; tapering ])osteriorly; peraeopods 3-7 walking, the 5th developed into a strong prehensile organ; pleon narrow, pleopods birami: urosome 3 segments, the last two coalesced; branchial pouches at 4-6 peraeon segments; oiistegites at 2-5 peraeon segments of mature females.

Ainphipods when born arc apprdxiniatcly a miniature of the adult form, but they are seldom an exact replica of the latter. Generally speaking, the iiientification of the adult specimens of this family is very certain; l)roblems arise on the identificalion of the young. Some of the structural characters and proportions of body ]>arts arc of sjjccific conslancy in the malure forms, but arc indistinct in the younger stages in which one spccics is often like another. The following specific diagnoses are therefore based on the characteristics found in the adult form. The change of forms during growth for each species, however, are described wher­ ever the material and lileralure are availal)le.

Genus Phronima L a t r e i l l e .

Phronima. L.\theille, 1802: 38 (original diagnosis). Leach, 1815: 355 (detailed diagnosis). Claus, 1872b; 467 (first descri])tion of male specimen of this genus). B ovallils, 1889: 341-353 (diagnosis; synonymy; literature survey; key). VossELEH. litOl: lOff. (revision). SxEpnExsEN. 1924: 113-114 (bibliography; key; propagation and vertical migration). SiiiH and Dvnbar, 1963 (key; identification; distribution). Bivonia. Cocco, 1832: 208 (original description; male).

L a tk i:ill i;’s original diagnosis for the genus seems to be inadequate; the following diagnosis is adapted from VossELER (1901) a n d C h e v r e u .x a n d F ace (1925): Head high and conical: outer ])late of maxilla 1 finely serrated; all 7 peraeon segments free, lower than head, and tapering posteriorly; the first two peraeon segments short, and usually much higher than the following; coxal plates of peraeopods entirely coalesced with peraeon segments, those of the peraeopods 3-5 still slightly recognisable; carpus of peraeopod 5 strongly dilated and, together with metacarpus, fortiiing a perfect subcheliforni hand; the last two urus segments fused together; all uropods with a styliform peduncle and two sharp-pointed rami; uropod 2, shortest of the three, but well tieveloped in both male and female.

Phronima sedentaria ( F o r s k a l ) . Fig. la-m .

Cancer sedenlarius. Fobsk.4l, 1775:xxi, 95-96 (original description; Mediterranean). Gammarus sedenlarius. Schol' sb o e , 1802: 11, fig. 1-6 (description with comment). Phronima sedentaria. Latreille. 1803: 291 (description). L e a c h , 1815: 355 (description; Burray in Shetland). Risso, 1816: 120 (description; compared with P.cuslo; Mediterranean). Delle Chl\je, 1841: pi. 33, fig. 5-7 (in the barrel of Dolioliiim papillosum). Pagenstecher, 1861, 15-41, pi. 1-3 (morphological transformation; circulation; struc­ ture of eyes: Mediterranean, between Nizza and Villefranche). B a te , 1862: 316-317, pi. 51, fig. 1 (synonymy; distribu­ tion). C l a l s . 1862: 195-196, pi. 19, fig. 1, 4-6 (structure of circulatory system; confused with P. allanlica). Macdonald, 1874: 154-158 (anatomy and habits; S. Pacific). G o r d o n , 1881: 56-59 (within the tunicate barrel and medusae; hatching of young; Hillswick in .Shetland). Bovallils, 1887: 25 (listed). C h e v r e l x , 1887: 325, 328, 330, 331 (geographic and bathymetric distribution in eastern N. Atlantic and Mediterranean). B a r r o is , 1888: 50 (.\zores). S te b b in g , 1888: Ft. 1 (literature survey): Pt. 2: 1357-1361, pi. 162B (synonymy; description; morpholgical transformation; W. Pacific). Hovallius. 1889: 353-369. pi. 16, fig. 1-3 (in key; diagnosis: synonymy; extensive literature survey; detailed descrip­ tion of the female and male; combined with P. cuslos, P. Borneensis, P. novaezealandiae and Bivonia zanzara Cocco). Cui N. 1895: 109-129. pi. 7, fig. 2, 5 (young male only). C h e v r e u x , 1900: 136 (Azores, west of Bay of Biscay; from albacore stomach). N o rm a n , 1900: 133 (synonymy; off S. W. of Ireland). V o s s e l e r , 1901: 14-19, pi. 1, fig. 1-11 (synonymy; detailed description of mature and young of female and male; Atlantic); 1903 (in Lo Bianco, 1903): 278 (listed; Mediterranean). W a l k e r , 1903: 230 (S. \V. off Ireland). S te b b in g , 1904: 32 (Bay of Biscay). H o lm e s , 1905: 46 ((irand Manan: in the barrel of salp.) Tattersall. 1906: 27 (west coast of Ireland). Bigelow, 1909: 199-200 (Gulf Stream). H olm es. 1909: 490 (I-:. Pacific, off California). W a l k e r , 1909: 49 (western Indian Ocean). Minkiewicz, 1910 (morphological transformation; behaviour). S te b b in g , 1910: 475 (listed; off S. African coast). C h ilto n , 1911: 308-309 (in barrel; Slew art Island). S t e u r , 1911: 673 (Adriatic). P e a r s e , 1913: 378 (Gulf of Mexico). S t e w a r t , 1913: 254 (Madeira). B io e lo w . 1915: 279 (in barrel; Gulf Stream). J o c b in and R o u l e , 1918 (in albacore stomach; Athmtic). C h ilto n , 1921: 233 (synonymy; t^hatliam Island). Stephensen, 1923: 34 (literature; young male; N. Atlantic, 61“14'N, 30'’28'W); 1924: 113-121, fig. 50-51, chart 15 (in key; synonymy; eastern N. Atlantic and .Mediterranean; vertical and geographic distribu­ tion; breeding season). S p.^.n d l , 1924 b: 264-265 (.\driatic). Ch e v r e u x and F.\g e , 1925: 393-395, fig. 396 (after \ o s s e l e h . 1901) (in key; synonymy; description; distribution). B ig e l o w , 1926: 54-58 (Gulf of .Maine; related to water mass). Mo g k , 1926, 1927a (morphological transformation; compared with P. allanlica; .\. .Atlantic); 1927b: 127-130, fig. 1 (captures and known recorcls of .\tlantic and Indian Oceans; young stages). S chellenberg , 1927: 639-641. fig. 44 (after V o s s e l e r , 1901) (in key; detailed description of mature and young female and male; distribution in .N. .Atlantic). H a l e , 1929: 229-230, fig. 226 (after Cla u s, 1872b) (listed, S. .Australian coast). I^irlo t, 1929: 110 (synonymy; diagnosis; eastern N.-Atlantic); 1930: 12-14 (synonymy; description; distribution; adjacent seasof Indo-.Australian .Archi|)elago). Ma h n a r d , 1930: 422 (S. .Atlantic, ofT Three Kings Islands and Campbell Island). B o o n e , 1930: 209-211, pi. 79 (detailed description of the female; captures from the adjacent waters of Monaco, Mediterranean and Cape Malo, Panama). B a h x a u d , 1932: 283-284 (breeding season; young in barrel; distribution; captures from .\. and S. .Atlantic, ofT P'alkland Island). Ch e v - REUX, 1935: 185-186 (N. Atlantic and Mediterranean). B ar.n a rd , 1937a: 4 (Macquarie Island); 1937b: 185 (young in barrel; .Arabian Sea, Gulf of Aden and Red Sea). L.'^g e n d r e , 1940: 177-181, fig. 15, 16 (bibliography; comjiared with P. allanlica; breeding season; as food of marine inhabitants; in albacore stomach, from Bay of Biscay). L in (}. 1941: 190-193 (Hong Kong). T h o r s t e in so .v , 1941: 92 (Gulf of .Alaska). S h o e m a k e r , 1945: 236 (synonymy; distribution; adjacent seas of Bermuda). B o u s f ie l d , 1951: 148, 162 (a young male probabh’ of this species; Gulf of St. Lawrence). M cH l g h , 1952: 164 (E. Pacific; in albacore stomach). H u r l e y . 1955: 166-170, fig. 12. and partly of 13 (in key: detailed description of female and male; known records of the adjacent seas of .\ew Zealand; captures from S.E. coast of New Zealand). R e id , 1955: 21 (listed; Atlantic ofT ^V. .Africa). H u r l e y , 1956: 17 (deep hauls from California waters). Sp r i.vg er and B ull is, 1956: (Gulf of Mexico). B a r y , 1959b: 325, 333, fig. 2, 5, tab. 1 (distribution in Xew Zealand waters related to the water masses). Ir ie , 1959: tab. 4 (adjacent seas of Japan). H u r l e y , 1960a: 280 (S. Pacific; remarks on distribution related to the water masses); 1960b: 113 (S. Indian Ocean). E v a n s, 1961: 232 (listed; Equatorial .Atlan­ tic). K a n e , 1962: 305-307, fig. 4 (synonymy; discussion of distribution in -New Zealand adjacent seas). \' in o g r ad o v . 1962: 23 (S. Pacific-Indian). S hih and D u .n b a r , 1963: text atul fig. 7a-d (in key; identification; bibliography; world distribution, with special reference to I.C.E.S. area). S ie g f r ie d , 1963: 9 (.Atlantic ofT S.^V. .Africa). Phronima custos. Risso, 1816: 121, pi. 2, fig. 3 (original description; Mediterranean). L a m a rck , 1818: 179 (brief diagnosis, .Mediterranean). Phronima allanlica. W h it e , 1847: 91 (misidentified; Borneo). St e b u in g , 1888: 1354, pi. 160 (misidenlified). Phronima Rorneensis. B a t e , 1862: 318, pi. 51, fig. 3 (original description; altered from P. allanlica. W h it e . 1847). Phronima novaezcalandiac. P o w e l l , L., 1875: 294, pi. 21, fig. 1, 2 (original description; Xew Zealand). St e b h in g . 1888: 1356, pi. 161B (Southern Ocean). Ch il t o n , 1912: 131-132 (Xew Zealand). P o w e l l , .A. W. B., 1947: 36 (listed). Phronima neo-zelanica (= P. novaezealandiae, P o w e l l ). T homson and Ch il t o n . 1886: 150 (distribution in adjacent seas of Xew Zealand). Phronima spinosa. B o v a l l i u s , 1887: 25 (original diagnosis; tropical Atlantic); 1889: 370-371, pi. 1 6 , fig. 8 - 1 8 (in key; detailed description of female). Phronima lenella. S t e b b i.n g , 1888: 1354-1356, pi. 161 .A (original description, central Pacific).

Diagnosis: Female. Total length of adult 25-42 mm. H,,: 6- 6'/,2; Hi subequal to 4. P/.A: 1.06i0.02; Plj Per,: 0.S4 ::0.02. Peraeopod 5, carpal process, well developed, about the same length as the carpal proper; carpal tubercle, single length much more elongate than the width, with 6-7 tooth-like projections, the distal tip of the tubercle slightly extended beyond the ventral margin of the metacarpus, which is much longer than the length of the ventral margin of the carpus, and is provided with a distinct tubercle on its dorsal margin. Outer and inner rami of the same uropod sube([ual. .Male. Total length of adult 8.5-12 mm. Hjj: 5*/2- 6 ; H^: 3\,-4. P .A: 1.13-0.04; Plj Per, slightly less than 1. ■Antenna 1. well developed, flagellum 7-jointed; antenna 2. very rudimentary: contains only a 2-jointed peduncle. Perae­ opod 5, carpal ])rocess short, not prolonged to reach the ventral margin of the carpus; carpal tubercle low, with a separate anterior tooth; metacarpus long, e.xtended far beyond the anterior margin of the carpus, no metacarpal tubercle present. Outer ramus longer than the inner in uropod 2, but subequal in uropods 1 and 3.

Remark.s:

P. sedentnria is the largest species of this family. .Members of the genus Phronima are, according to \ 'o s s e - l k r (lyoi), divided into two groups, based on the siriicture of antenna 2 in the males. P. scdenlarid ami P. afflnis are the only two species whose males do not possess well developecl antenna 2 ami are Iherefore put together in one group; the rest of the species are contained in the other. Although the validity of P. af/iitis is still doubtful (see page 25), nevertheless, it is equally impossible to consider it here as a synonym of P. sedentaria without checking the type specimen. Morphological Change with Growth. In the material examined in the present investigation, the present species provides the most detailed in­ formation on the change of form in the course of growth. Since the morphological changes in the earlier life seem to have a very close relationship with the stages of the growth they are considered in greater detail in the next chapter. The general pattern of the morphological transformation is essentially similar among species of this genus and the description of the earlier changes in the next chapter would possibly apply to the other species, which may not have enough material available for analysis.

Fig. 1. Carpus 5 (a-j) and antennae (k and ni) of Phronima sedentaria F o r s k a l . - Carpus 5: Female: a. 7.0 (total body length in mm); b. 8..S: c. 10.2; d. 13.5; e. 16.0; f. 21.2 and g. 28.5. Male: h. 5.5; 1. 7.5 and j. 9.0. - Antennae of mature males; k. Atlantic-E. Pacific form; Indo-\V. Pacific form. - (Scale, 1 mm. Except Subflg. f and g all are of the same magnification).

The carpal tubercle of peraeopod 5 in the female is somewhat bifid in the younger stages. When the animal grows older, the carpal tubercle becomes more and more elongated. In the meantime, the separate anterior tooth is brought closer and closer to the main body of the tubercle. When the animal reaches the maturity', the carpal tubercle has already become single. The metacarpal tubercle of peraeopod 5 does not appear until the animal reaches the size of 14 mm., but becomes very prominent in the next stage. Since peraeopod 5 is of such importance in specific identification, its change of morphology- from young to adult is show'n in fig. 1 . The changes of form in the carpus and metacarpus of peraeopod 5 in males are similar to those of the females in the young stages. However, when the male is maturing, the separate anterior tooth is kept sepa­ rated from the tubercle proper. (This aC'Counts for the diverse changes of form in carpus 5 of the two sexes). An illustration of the changes of carpus 5 in the males is shown in fig. 1.

Geographical Variation.

The identification of this species in the last century was highly controversial. Although S t e b b i n g himself was one of the victims (see his work on Challenger’s collection), he once wrote (1904), . . since the genus was instituted, writer after writer has been tempted to establish new species, each being in general less ready to accept the validity of his predecessor’s innovation than to follow his example by making a fresh one.” Specimens of this species collected from different parts of the occans have been established as new species by different taxonomists, e.g., P. Borneensis ( B a t e , 1862), P. novaezealandiae (L. Po\vi:i,i,, 1875). The latter is still listed by A. Powkll (1947) as a genuine species of the New Zealand fauna. The diverse opinions on the identification of this species, and also of other species of this genus, arc due, as one school claims, to geographical variation. To investigate the possibility that this explanation is true, a statistical comparison has been done on some of the important numerical specific characters of this species selected from random samples from different parts of the occans. The result is shown in Table 1. Apparently there are some sig­ nificant differences in one or more characters between samples from different waters but the general appear­ ance remains the same throughout. It is therefore probable that the controversial identification of this species in the past is due rather to the imperfection of the illustration. Drawings in the literature based on specimens of different stages are quite dissimilar from each other. The antenna 2 of the male of this species presents, however, a more interesting problem. It is very small in this species, but two different sizes are found among the adults. The specimens collected from the western Pacific and the Indian Ocean possess a longer antenna than those from the Atlantic and the eastern Pacific (fig. 1 k and m). The antenna 2 of the former areas is of the order of 0.2o mm., that of the latter areas is of the order of 0.1 mm. This morphological difference has not been reported by past investigators. In the Dana material, the male recorded from the most southerly station of the eastern Africa coast (Dana Station 3969) belongs to the long antenna 2-group, and the male caught from the most southerly station of the western Africa

Table 1 a. The t-test of means of several numerical characteristics among female specimens of Phronima sedenlaria from four Dana Stations.

1371 -1018 3722

a b c 4018...... 0.0187 0.0625 0.30 Peraeon/Pleon a b c 3722...... 0.0020 0.0157 0.13 0.0207 0.0539 0.38 ab c 3642 ...... 0.0280 0.0530 0.53 0.0093 0.0569 0.17 0.0300 0.0624 0.71

4018...... 0.0219 0.0630 0.35 Per, PI, 3722...... 0.0020 0.0571 0.04 0.0239 0.0469 0.51 3642...... 0.0440 0.0553 0.80 0.0221 0.0444 0.50 0.0460 0.0355 1.30

4018...... 0.0037 0.0176 0.21 Peraeon seg. 7;Peraeon 3722...... 0.0100 0.0126 0,80 0.0073 0,0197 0,37 3642...... 0.0110 0.0100 1.10 0.0083 0.0182 0.46 0.0100 0.0134 0.75

4018...... 0.0004 0,0428 0,001 5th basos Peraeon 3722...... 0,0080 0.0241 0.33 0.0076 0,0404 0.19 3642...... 0,0630 0,288 2,11* 0.0634 0,0434 1,46 0,0710 0,251 2,83* a. DifTerence of the means; b. Standard error of the difference between two means; c. Calculated t-value, - Each sample is composed of 10 adult specimens, - t-value at 95"/, level (d. f. = 18) = 2.10, at 99 “ = 2.88. - • Significant difference at 95" , level. Table 1 b. The t-tests of some numerical characteristics among male specimens taken from Dana Stations 3736 (W. Pacific), 3996 (E. Atlantic) and Longlining Stations (E. Pacific).

Dana Station 3736 Dana Station 3996

a b e Dana Station 3996...... 0.088 0.0437 2.01 Peraeon/Pleon a b c [.onglining Stations...... 0.021 0.0503 0.42 0.109 .0332 3.28**

Dana Station 3996...... 0.069 0.0317 2.18* Per, Pl^ Longlining Stations ...... 0.008 0.0260 0.31 0.075 0.021 3.57**

Dana Station 3996...... 0.024 0.0132 1.82 Pcracon seg. 7/Peraeon Longlining Stations...... 0.006 0.0130 0.46 0.018 0.0129 1.39

Dana Station 3996...... 0.007 0.0203 0.34 Basos 5/Peraeon Longlining Stations...... 0.030 0.0251 1.20 0.023 0.0235 0.98

For explanations see Table la. - • Significant difference at 95" „ level. - ** at 9 9 " level. coast (Dana Station 3975) belongs to the short antenna 2-group. It is evident that one of the boundaries of this morphological difTerence is the area south of the African continent. The Dana collection provides no male specimens from the eastern Pacific; its most eastern station reporting a mature male, is north of New Guinea (Dana Station 3768). The antenna 2 of CCOKI collection belongs to the short group. Since there is a wide gap between the eastern and western Pacific in the distribution of the male specimens of this species, it is not possible here to propose an exact boundary of this character in the Pacific Ocean. The meaning of the mor­ phological difference in the antenna 2 will be further discussed in the Discussion (Chapter V).

Phronima atlantica G u e r in . Fig. 2 a-k. Phronima atlantica. Guerin, 1836a: 7, pi. 18, fig. 1 (original description). Milne-Edwards, 1840: 93 (synonymy; brief description; P. custos considered probably of the same species). B.\te, 1862: 318, pi. 51, fig. 3 (S. Atlantic). Streets, 1882: 5-8, pi. 1, fig. 1, la, 2 (detailed description of male and female; against Claus’ opinion to combine this species with P. aedentaria; Central Pacific). Bovallius, 1887: 25 (listed). Stebbing, 1888: Pt. 1 (literature survey), Pt. 2: 1351, pi. 160 (I^acific). Bovallius, 1889: 374-377, pi. 16, fig. 19-26 (in key; literature survey; description of female). Chevreux, 1900: 137 (N. Atlantic). Vosseler, 1901: 21-27, pi. 2, fig. 1-10 (detailed description of female and mature and young male; Atlantic). Vosseler, 1903 (in Lo Bi.\nco, 1903): 278 (listed; Mediterranean). W alker, 1903: 223 (southwest off Ireland). Bigelow, 1915: 279 (Gulf Stream). Spandl, 1924a: 24 (Red Sea). Stephensen, 1924: 121-125, chart 16 (in key; synonymy; captures, vertical occurrences, size and propagation in Mediterranean and eastern N. Atlantic; world distribution). C h e v r e u x and F a c e , 1925: 395-396, fig. 397 (after V o s s e le r , 1901) (in key; synonymy; description; distribution). Bigelow, 1926: (Gulf of Maine; related to Gulf Stream). D u d lic h , 1926: 17-1 (breeding cycles in the -Mediterranean). -Mogk, 1926, 1927a (morphological transformation; N. Atlantic; compared with P. sedentaria); 1927b: 131-133 (captures and known records from literature in the Atlantic and Indian Oceans). Schellexberg, 1927: 641-643, fig. 45 (after V o s s e le r , 1901) (in key; detailed description of mature and young male and female; distribution in X. Atlantic). Pirlot, 1929: 112-114 (synonymy; diagnosis; eastern Atlantic). B a r n a r d , 1930: 422 (S. Atlantic and the adjacent waters of Three Kings Island and Campbell Island). P irlot, 1930: 14-15 (the adjacent waters of Indo-Malayan .\rchipelago). B a r n a r d , 1932: 285 (distribution; captures from X. and S. Atlantic). C h e v r e u x , 1935: 184 (X. .\tlantic and Mediterranean). B a r n a r d , 1937b: 185 (X. Arabian Sea); 1940: 484, 541 (Durban, Africa; in key). L e g e n d r e , 1940: 181-185, fig. 17, 18 (bibliography; compared with P. sedentaria; breeding season, as food of marine habitants; in stomach contents of albacore form the Bay of Biscay). Shoemaker, 1945: 236 (synonymy; brief descrip­ tion; the adjacent waters of Bermuda). M c H u g h , 1952: 164 (eastern X. Pacific coast; in albacore stomach). H u r l e y . 1955: 166, 170 (in key; compared with P. aedentaria). R e id , 1955: 20 (listed; Atlantic off W. Africa). Irie, 1958: 142, 143 (listed; Tsushima Current); 1959: tab. 4 (adjacent seas of Japan). H u r l e y , 1960b: 113 (S. Indian Ocean). E v a n s, 1961: 232 (listed; Equatorial Atlantic). Grice and H art, 1962: appendix table 3 (listed; Atlantic between Bermuda and -New York). Vinogradov, 1962: 23 (S. Pacific-Indian). Shih and D u n b a r , 1963: text, fig. 2a-d (in key; idenfication; bibliography; world distribution, with special reference to I.C.E.S. area). Siegfried, 1963: 9 (listed; Atlantic off south­ western Africa). Phronima sedentaria. Cl a u s, 1872a: 331-338, pi. 26, fig. 1, 3 (inisidentified; female P. atlanlica considered to be the young of P. sedentaria; mature male P. allantica considered to be the mature male P. sedenlaria). Ch u n , 1889b: 378­ 382 (misidentified; in agreement with Cl.\u s , 1872a); 1895: 109-129. pi. 7, fig. 1, 3, 4 (niisidentifled, mature male P. atlanlica for mature male P. sedenlaria).

Diagnosis. Female. Total length of adult: 12-25 mm. H^: Hj subequal to 3. P/A: 0.92 - 0.02; Plj/Per,: 0.70 ±0.04. Peraeopod 5, carpal process moderate, only slightly protruded beyond the ventral margin of the metacarpus; carpal tubercle bifid, weaker than the carpal process, not protruded beyond the ventral margin of the metacarpus, with 4-5 toothlike projections on the posterior margin; metacarpal tubercle indistinct. Uropod 1, outer ramus slightly shorter than the inner; uropod 2, outer ramus longer than the inner; uropod 3, outer ramus subequal to the inner. Male. Total length of adult: 8-11 mm. Hj subequal to 3. P/A: 1.14±0.04; Plj/Per,: 0.95i0.04. Anten­ na 1, well developed, flagellum 7-jointed, first flagellate joint longer than two-thirds of the head height; antenna 2, well developed, usually longer than antenna 1, flagellum with 11 to 12 joints. Peraeopod 5, carpal process nioderateh de­ veloped, protruded downward slightly beyond the ventral margin of the metacarpus; carpal tubercle, shorter than the carpal process, with a separate anterior tooth, the posterior part containing 4-5 tooth-like projections; metacarpus moderately longer than the ventral margin of the carpus. Uropod 2, outer ramus slightly longer than the inner; uropods 1 and 3, both rami subequal.

Remarks. The size of this species is second to P. sedentaria in this family. It is also very widely distributed. The earlier

carcinologists, for instance, C la u s and C h u n , confused it with P. sedentaria. In the most extreme cases, they have considered the female of P. atlanlica as the young form of the female P. sedenlaria and the male

of the former species, possessing well developed antenna 2 , then had to be named the mature form of the latter. The genuine adult male P. sedenlaria was said to be the young form, because the antenna 2 was still “rudimentary”. Morphologically, this species is also very closely associated with P. solilaria, which has been

considered to be a variety of atlanlica since V o s s e l e r (1901). The reasons for re-establishing the latter as a separate species will be discussed later (p. 17).

Morphological Change with Growth. It is very difficult to distinguish the younger form of this species from that of P. sedentaria. The very young stages of all species of this family are so alike that identification to species is difficult unless the young in a sample are particularly associated with adult females; for instance, if they are found inside the maternal brood pouch, or within the tunicate barrel with the mother. M o g k (1926, 1927 a) made detailed morphological comparison of this species with P. sedenlaria. He was able to distinguish the two even in very young stages by a series of numerical measurements of the body parts. In the present study, although the measurements taken from the larger specimens are in good agreement with M o g k ’s findings, it is difficult to apply the characteristic measurements to the very young stages. There are not many specimens of these stages present; also the vagueness of the segmentation makes correct meas­ uring almost impossible. The youngest form free of the egg membrane found inside the maternal brood chamber is about 0.50 mm. in length; the next stage is about 1 mm in size. The morphological characteristics of these stages arc the same as those described for P. sedenlaria. If they were not found inside the brood pouch, it would be im­ possible to identify them to species. As in P. sedentaria, the male and female specimens of this species are readily distinguishable at a length of 4.5 to 5.0 mm. The antenna 2 of the male at this stage is represented by a small but distinct protrusion at the medial inferior corner of the lower group of eye facets. The antenna 1 is about the same length in both sexes, but the diameter is apparently thicker in that of the male. The pleopod rami are composed of four joints in both the male and female at this stage. The male, previous to the penultimate stage, has the external features of the female, with the exception of the antennae. This similarity suddenly becomes less obvious when the male reaches the penultimate stage. and disappears almost entirely when the male is sexually mature. A diagram to show the change of form in the carpus of paraeopod 5 during the course of growth, is shov.n in fig. 2 a-k.

Geographical Variation. This specics presents less of a problem in the literature than P. sedentaria. It seems to vary less, geographic- all v, than the other members of the family.

Fig. 2. Carpus 5 of Phronima atlantica G u e r ix . - Female: a. 4.3 (total body length in mm); b. 6.2; c. 7.3; d. 8.5; e. 11.8 and f. 17.5. Male; g. 4.1; h. 6.1; i. 6.9; j. 8.0 and k. 9.4. - (Scale, 1 mm. Except subfig. e and f all are of the same magnification).

Phronima solitaria G u e r in . Fig. 3 a-d.

Phronima solitaria. G u e r ix , 1836a: 7, pi. 18, fig. 1 (original description); 1936b: 21, pi. 25, fig. 4 (listed). B o v a l l iu s, 1889: 372-373, pi. 17, fig. 4-7 (synonymy; description; Atlantic and Indian Oceans). Phronima cuslos. B a t e , 1862: 318, pi. 51, fig. 2 (description; Mediterranean). Phronima megalodous. St e b b i.v g , 1888: 1353, pi. 162A (detailed original description; N. Atlantic and N. Pacific). Phronima atlantica var. so/i/ar/a. V o sse l e r , 1901: 23, pi. 2, fig. 5 detailed description; comparison with P. atlantica; -\tlantic). St e p h e n s e n , 1924: 125 (synonymy; Mediterranean; in key). M o g k , 1927a: 59, fig. 31 (morphological trans­ formation); 1927b: 133, fig. 3 (captures and known records from Atlantic and Indian Oceans). P ir lo t, 1929: 112 (Morocco coast). B a r n a r d , 1930: 423 (S. Atlantic; 59° S, 25°I5' \V); 1937b: 186 (Red Sea and N. Arabic Sea). Sh o e ­ m a k e r, 1945: 236 (listed; adjacent seas of Bermuda). Shih and D u n b a r , 1963: text, fig. 2e and 2f (in key; identification; world distribution). Sie g f r ie d , 1963: 9 (listed; waters off southwestern Africa).

Diagnosis. Female. Total length of ault: 13-24 mm. H,,: 5V2- 6 ; Hj subequal to 3. P/A: 0.90±0.03; Pli/Perj: 0.66 ±0.05. Peraeopod 5, carpal process strong and curved; carpal tubercle single, narrow but strong, with 7-9 tooth-like projections, the ventral tip of the tubercle protruded downward beyond the ventral margin of the metacarpus, and almost reaching the level of the tip of carpal process. Metacarpal tubercle present but weak. Outer ramus and inner ramus subequal in all uropods.

Remarks. This species was first taken from coastal Atlantic water, not far away from the estuary of R. Plata (S.

America), and briefly described by Gl e r ix (1836 a). B o v a l l u s (1889) then made a more detailed descrip­ tion. The specimen that was identified as P. ciistos by B a t e (1862) belongs to this species, judging from the shape of the carpus of peraeopod a and the ratio of the 7th peraeon segment to the 1st pleon segment in his drawing, although this specific name cuslos, created by Risso (1816), is a synonym of P. sedentaria. P. soUlaria is easily distinguished from P. atlantica by the shape of the carpus of peraeopod 5, and from P. sedentaria by the much larger length ratio of the 7th peraeon segment to the 1st pleon segment. The said carpus in atlantica and sedentaria is more or less triangular in shape, with a narrow proximal end and a some­ what straight anterior border; while in solitaria it is provided with a pronounced convex anterior border. This difference is obvious when comparing fig. 2 and fig. 3. VossELER (1901) considered that P. solitaria is only a variety of P. atlantica. He argued that although the form of the carpus of peraeopod 5 is very similar to that of sedentaria, the body proportions, especially the length ratio of the 7th peraeon segment to the 1st pleon segment and the length of the head to the first peraeon segments, are nevertheless much closer to those of atlantica. He stated further that in the younger

stages, the carpal tubercle of peraeopod 0 in solitaria is, as in atlantica, bifid and therefore shows a much closer affinity to atlantica than to sedentaria. As is described l)efore, the carpal tubercle of peraeopod 5 in P. sedentaria is also bifid in the younger stages. While the growth goes on, the anterior separate tooth of the tubercle comes closer and closer to the others, and finally the tubercle becomes single when the animal is mature. This change is likewise observed in solitaria. Other species of the genus Phroniina also exhibit some similarity to atlantica in the body proportion. For instance, the length ratio of the 7th peraeon segment to the

1st segment is of the same order in pacifica and curuipes as in atlantica (Sum and Dl n b a r , 1963). It is thus

clear that the characters which V o s s e l e r considered of significance in relating solitaria to atlantica are also found in the other species. As demonstrated by the collections of the Dana expeditions examined in the present investigation, P. solitaria is widely distributed in all oceans as are other Phronima species, and is recognizable from very young stages. No male specimens of P. solitaria, were found in this study. Female specimens with eggs of juveniles in the brood pouch have been found on several occasions. From the foregoing it follows that P. solitaria does not seem to be either a sympatric or allopatric variation of the normal form of P. atlantica. It is impossible to judge from the morphological characters alone whether solitaria is closer to sedentaria or to atlantica. However, out of the thirty-eight stations of Dana materials positive for solitaria, the species is found together with sedentaria and atlantica in thirty-t^vo (84.2 ®/q), and alone with sedentaria in six stations (15.8 ®/q). It is possible that solitaria is the hybrid form of sedentaria and atlantica. To determine this point, more ecological, physiological and cytological studies are required. It seems reasonable at this moment to restore the specific status of solitaria, in spite of the fact that no male of the species has been found.

Morphological Transformation. In addition to the change of the bifid to the single carpal tubercle in peraeopod 5 described above, the rami of uropod 2 also exhibit a gradual change corresponding to the increase of the animal size (fig. 3). In the

Dana-Report No. 74,1969 3 younger stages, the outer ramus of uropod 2 is apparently longer than the inner. When the animal reaches the size of about 13 mm, i.e., almost the mature stage, the difference in the length of the two rami is insig­ nificant.

Geographical Variation. Specimens of this species were found in abundance at any station. If mature specimens from the Dana stations ;^997 to 4010 (East African water) are taken as a sample, then the numerical characteristics of the individuals taken from other parts of the oceans usually fall within the fiducial limits (at 95 “/o level) of the individual variation of the sample.

Fig. 3. Carpus 5 of Phronima solitaria Guebi.v. - Female: 8.2 (total body length in mm); b. 11.0; c. 14.6 and d. 24.1. - (Scale, 1 mm)

Phronima pacifica S t r e e t s . Fig. 4 a-i.

Phronima pacifica. St r e e t s , 1877: 128-130 (original description; compared with P. sedentaria and P. allanlica; N. Pacific); 1882: 6-8, pi. 1, fig. 3 and 3a (detailed description of female; range of distribution in Pacific). V o s s e l e r , 1901: 29-32. pi. 3, fig. 4-7 (detailed description of female and brief description of young male; Atlantic); 1903 (in Lo B ianco, 1903): 278 (listed; Mediterranean). W a l k e r , 1909: 51 (W . Indian Ocean). SaANDL, 1924: 25 (Red Sea). S t e p h e .v s e n , 1924: 130 (in key; synonymy; captures from the Atlantic; world distribution). M o g k , 1927a: fig. 31 (structure of carpus 5); 1927b: 140 (S. Atlantic). B a r n a r d , 1930: 423 (discussed with P. colletli; Atlantic); 1932: 285-286 (discussed with P.colletti] Atlantic). Ciie v r e c x , 1935: 185 (N. Atlantic). S h o e m a k e r , 1945: 235 (synonymy; the adjacent waters of Bermuda). R e id , 1955: 21 (west African coastal water), S h ih and D u .n b a r , 1963, text, fig. 6 (in key: identification; world distribution). Sie g f r ie d , 1963: 9 (southwestern African coastal water).

Diagnosis. Female. Total length of adult: 6.5-14.5 mm. H^: SVj-SVs; Hj: 2V3- 3V3. P/A: 0.89±0.05; Plj/Per,: 0.71 ±0.03. Peraeopod 5, merus, wider than long, posterior border strongly produced; carpus dilated, the proximal posterior corner produced; carpal tubercle with 4 to 5 tooth-like projections and a separate anterior tooth; carpal process protruded slightly beyond the ventral margin of metacarpus; length of metacarpus subequal to the width of the ventral margin of carpus. Outer and inner rami of all uropods subequal.

Male. Total length of adult: 6.5-8.5 mm. H^: 5%-6*/4; Hj: 3-3V2- P/A: 1.16 ±0.07; Plj/Per,: 0.94 ±0.07. Antenna 1, well developed, flagellum 6-jointed, 1st flagellate joint about three quarters of head length; antenna 2, well developed, about one half longer than antenna 1, flagellum 15-17-jointed. Peraeopod 5, posterior border of merus very strongly produced to form a semicircular arc, width of merus larger than height; carpus, wider than long, the proximal posterior corner produced, carpal process moderately developed and curved, carpal tubercle with a separate anterior tooth and 4 tooth-like projections, of which, the first is somewhat isolated from the rest, the last two usually low; metacarpus, subequa) to the ventral margin of the carpus. Outer ramus subequal or slightly longer than the inner ramus in uropod 2. Remarks. The female of this species is easily distinguished from the other species by peraeopod 5. The strongly produced posterior border of the merus and the almost trapezoid shape of the carpus constitute the most distinctive characters. The male of P. pacifica has never been fully described. Str eets (1882) stated that the carpus of pcraeo- pod 5 in the male is similar to that in the female. Vosseler (1901) recorded one young male from the German Plankton Expedition station 184, and said that the carpal tubercle is flat and with 3 tooth-likc projections, of which the first is large and separated, the last two small. He also found three male specimens of size, 8.5 mm, larger than the average size, 7-7.5 mm of the adult male P. colletti in his material. These large speci­ mens possess all the essential characteristics of male colletti except the size, and he did not exclude the possibility that they were male pacifica; if they were, he proposed that a close relationship exists between these two species. B a r n a r d (1930) found a male characteristic of colletti taken together with the female pacifica from the British Antarctic Expedition station 50. Since there are no other specimens belonging to P. colletti in the collection of this expedition, he assigned it to P. pacifica. He agreed with M o g k (1927 b) that females of pacifica and colletti may be dimorphic forms of one species, though the colletti form is more abundant. M o g k found specimens which show transitional characters between these two species. During the preliminary examination of the Dana collection male specimens that were provisionally called “colletti-gcoup”, were sorted out for more detailed study. This group was later found to be composed of three types, distinctly distinguished from each other by some essential morphological features, e.g., the length and joint number of the antenna 2, the shape of the carpus of peraeopod 5, and the length relationship of the outer and inner rami of uropod 2. The distribution of these three types, when compared with that of the female specimens, shows a correspondence with the females of pacifica, colletti and ciirvipes. Since these male types are clearly different from each other in certain characters and each, in addition to the pattern of distribution, is found to have some morphological characteristics similar to the female of one of the three species mentioned, it is believed that each type of this “colletti-group" is in fact the male of the corresponding female species.

Description of Male. (Fig. 4 a-i). More detailed information on the male is required in addition to the brief diagnosis listed above. The following description is based on specimens taken from the Atlantic at Dana Station 3998.

Head, height in length frontal surface flat, with a ridge elevated between the frontal and lateral surface. Lower group of eye facets very well developed, forming a highly swollen structure on the central lateral surface. Antenna 1, inserted on the frontal surface medial to the lower group of eye facets, slightly higher than the lower one-third of head height, 1st flagellate joint */, of head height and V4 longer than the rest five flagellate joints together; antenna 2, inserted on the frontal surface, medial to the antero-inferior corner of the lower group of eye facets. Peraeopods, First: basos, width about of length, anterior margin more or less straight, posterior margin slightly dilated in the lower half, length about V4 longer than the next 3 joints together; distal posterior margin of carpus pro­ duced posteriorly, with the ventral margin serrated; ischium, width subequal to length; metacarpus slender, subequal to the length of carpus; dactylos small, less than in metacarpus. Second: basos, V5 longer than that, of first, and * 3 longer than the next 3 joints together; distal posterior margin only slightly produced and protruded downward. Third: basos. * 5 longer than that of the first, anterior margin straight, posterior margin dilated near the distal end, with a tiny seta inserted at the distal posterior corner; length of the next 4 joints of basos, 2/5, ®/j and ^/, respectively; posterior margin of merus, carpus and metacarpus serrated. Fourth: similar to that of the third but slightly wider: Fifth: basos. length about 2 in that of the first, anterior margin slightly convex, posterior margin with a short and blunt [)rocess at the distal end; ischium, slightly longer than*/4 in basos, longer than wide; merus, subequal to ischium in length, anterior margin straight, posterior margin strongly convex, width 1/5 larger than length; carpus, in basos, anterior margin anteriorh oblique, proximal posterior corner strongly produced, making the carpus more or less trapezoid in shape as in the female, width about Vs larger than length, carpal process moderately strong and curved backward slightly, carpal tubercle with a separate anterior tooth and 4 tooth-like rpojections, of which the first is somewhat isolated from the rest, the last two very low; metacarpus arched, subequal to the ventral margin of carpus. Sixth: basos, ’/g in that of the fiftli, subequal to the next 3 joints together, anterior margin straight, with a very tiny process at the distal end, posterior margin slightly curved; ischium arched, carpus about 2 in merus and one half longer than the metacarpus. Seventh: basos, subequal to that of the fifth, and V4 longer than the next 3 joints together; otherwise similar to the sixth. Pleon, about shorter than peraeon. Ei)imeral plates most well developed in the second pleon segment, a deep notch present at the posterior half of ventral margin in the first segment. Urus, subequal to the third pleon segment, the coalesced segments longer than one half of the first urus segment. Uropods, lateral and medial margins almost parallel in the first and third, but widened distally in the second ; outer ramus and inner ramus subequal in the first and third, subequal or slightly longer in the second; length ratio of peduncles: 10:7:8.3; length ratios of outer ramus to the peduncle: -/j, and

Fig. 4. The male of Phronima pacifica S t r e e t s . - a. Lateral view of an adult, 6.8 mm, Dana statiort 3998. b-h. Peraeopods 1-7 and i. uropods of the same. - (Scale, 1 mm. Except subfig. a all are of the same magnification)

Morphological Change with Growth. The c arpal tubercle of peraeopod 5 in the female has three tooth-like projections in addition to the separate anterior tooth in the younger stages, but increases to four or five in the adults. The first of these processes is far separated from the remainder in the young animals but becomes closer in the later stages, and is con- tigous -with the rest in the mature stages. The separate anterior tooth is far apart from the tubercle in young animals but almost continuous with the latter in the adults. The inner ramus of the second uropod is almost one half of (he length of the outer one, but becomes subequal in the adults. In the young stages, the male generally very much resembles the female. The length ratio of the 7th

peraeon segment to the 1 st pleon segment is how ever smaller in the male from a very young stage. The carpal tubercle of peraeopod 5 in the male seems to change little from young to adult. In the mature male it is there­ fore similar to that of the young female rather than to that of the mature female. Geographical Variation. There seems to be no difference in the general from of specimens taken form different parts of the oceans. However, statistical tests have shown significant difTerences in certain numerical characteristics between samples taken from the Indo-Pacific region and from the Atlantic Ocean olT western Africa. For instance, in the females, the length ratio of the 7th peraeon segment to the 4th to 6 th segments together is apparently larger than 1 in the former (1.156) and smaller than 1 in the latter (0.985). A /-test of the means of these two samples gives a / value of 6.58, which means that P is less than 0.001 (d.f. = 20). In the males, the only difference found in samples from these two areas is the length ratio of the first three peraeon seg­ ments to the next three peraeon segments, 0.623 vs. 0.669. The /-test of the difference between these two means shows that P is less then 0.01.

Phronima colletti B o v a l l i u s . Fig. 5 a-t. Phronima colletti. Bovallius, 1887: 25 (listed; brief original description; S. Atlantic); 1889: 378-382, pi. 16, fig. 27-47 (in key; detailed description of male and female; synonymy). Chun, 1895: 109fl., pi. 8, fig. 1-5 (Atlantic between the Gulf of Biscay and Canary Islands). Chevreux, 1900; 137 (listed; N. Atlantic). Vosseler, 1901; 32-36, pi. 3, fig. 8-10 (synonymy; detailed description of male and female; Atlantic). Stephensen, 1924: 127-130, chart 18 (syno­ nymy; in key; captures from and vertical distribution in the Mediterranean and Atlantic; world distribution). Chev­ reux and Fage, 1925: 396-397, fig. 395 (after Bovallius, 1889) and 398 (after Vosseler, 1901) (in key; description; distribution). Mock, 1927a: fig. 31 (carpus 5, illustrated); 1927b: 139-140, Tig. 7 (size and propagation; captures and known records from Atlantic and Indian Oceans). P irlot, 1929: 114-115 (synonymy; distinctive characteristics; di­ stribution; captures from eastern N. Atlantic); 1930: 554 (Indonesian waters). Barnard, 1932: 286 (N. Atlantic). Chevreux, 1935: 184-185 (listed; N. Atlantic). Barnard, 1937b; 186 (N. Arabian Sea and Gulf of Aden); 1940: 484, 541 (Indian Ocean off Durban, S. Africa; in key). Shoemaker, 1945; 236 (synonymy; the adjacent waters of Bermuda). R eid, 1955: 20 (listed; Atlantic off western Africa). H urley, 1956; 17 (deep hauls from California waters). Irie, 1958; 142, 143 (listed; Tsushima Current); 1959: tab. 4 (adjacent seas of Japan). H urley, 1960a: 280 (S. Pacific). E vans, 1961: 232 (Equatorial Atlantic). Shih and D unbar, 1963, text and fig. 3a-d (in key; identification; bibliography; world distribution, with special reference to I.G.E.S. area). Siegfried, 1963: 9 (listed; Atlantic off southwestern Africa). Phronima sedentaria. Claus, 1872a: 331-338, text fig. 1, pi. 26, fig. 2, pi. 27, fig. 11 (misidentified, male only). Phronima bucephala. Giles, 1887: 213-217, pi. 3, fig. 1-2 (original description; Bay og Bengal). Phronima diogenes. Chun, 1889a; 527-531, pi. 3, fig. 5-6 (original description; compared with P. sedentaria and P. atlantica; Atlantic); 1889b; 379 (deep and surface water of Atlantic). Phronima gasti. D udlich, 1926: 134-137, fig. 1-3 (original description; Mediterranean).

Diagnosis. Female. Total length of adult; 6.5-18(?) mm. H^: 6-6Va; Hj: P/A: 0.96i0.03 (for Atlantic form only), Pli/Per,: 0.81 i0.03 (for Atlantic form only). Peraeopod 5, merus, slightly longer than wider, posterior margin rounded; carpus, narrow, carpal tubercle low, with 3-4 tooth-like projections and a separate anterior tooth, carpal process moderate, slightly bent backward; metacarpus, subequal to the length of the ventral margin of carpus. Outer ramus subequal to or slightly longer than inner ramus in uropod 2. Male. Total length of adult: 6.3-8.5 mm. H^: Hj: 8- 31/2. P/A; 1.13i0.07; PlJPer,: 0.94 ±0.07. Antenna 1, well developed, flagellum 5-6-jointed, 1st flagellate joint subequal to or longer than three quarters of head length; antenna 2, well developed, one half or more longer than antenna 1, flagellum 12-17-jointed. Peraeopod 5, carpus, similar to that of female, but wider in shape; metacarpus, subequal to the length of the ventral margin of carpus. Outer ramus subequal to or slightly longer than the inner ramus in uropod 2.

Remarks.

B o v a l l i u s (1889) has given a detailed description of this species. The female is readily recognized by the slender shape of the body. The head is somewhat bent down; its crown is prominent as compared to that of other species. Peraeopods 3 and 4 are slender, elongate and subequal in length. They are at least longer than one-third of the total length of peraeopod 5. The male, on the other hand, has been confused with the male of other species, namely P. curvipes and P. pacifica. This is mainly due to the fact that among the genus Phronima, males of different species resemble each other more than they resemble the females of their ow n species, and the similarity is especially marked in these three species. The situation is made more confused by the illustration given in V o s s e l e r ’s (1 9 0 1 ) monograph. It is doubtful whether his drawing of the male collelli, appearing on fig. 8 of plate 3, is taken from male collelli or male pacifica. The specimen on which this figure is based is taken from eastern S. At­ lantic (7.8° S, 17.3° W), without the capture of female collelli or pacifica at the same time. In the Dana collection, both females and males of these two species are found abundantly close to this particular locality, i.e., Dana Stations 3998 and -1000. Judging from the shape of the merus and especially the carpus of peraeopod

5 and the number (17) of the flagellar joints of antenna 2 in V o s s e l e r ’s drawing, it seems most probable that this specimen is a male of pacifica rather than of collelli. Numerical characteristics measured from this drawing also show a remarkable correspondence to those of P. pacifica, and are well fitted in the discrimi­ nant function. It is therefore suggested that the drawing of the so-called "P. coUelti” in V o s s e l e r ’s drawing is actually taken from a specimen of male P. pacifica. If this is true, it might well explain why there are so few records of male pacifica in the literature, and where it is recorded, the authors usually express uncertainty in their decision and are shy to give any drawing to demonstrate it, especially since V o s s e l e r ’s work has been unanimously considered to be the standard for this family. From the present investigation, the male of this species can be distinguished from the males of P. pacifica and P. curripes mainly by the shape of peraeopod 5 and uropod 2. In peraeopod 5, if the length of the carpus is measured along its anterior margin, from the proximal end to the tip of the carpal process, and the width, the widest portion of the carpus horizontally, then the length/width ratio is about 1 for male collelli and much larger than 1 for the other two species. The uropod 2 is somewhat similar to that of male P. pacifica, i.e., with the inner ramus subequal to or only slightlj' shorter than the outer ramus, but its peduncle differs from that of the latter species by the fact that it is only slightly dilated, distally. The carpal tubercle of peraeo­ pod 5 of this species on the other hand is more like that of the male curuipes in having the projections closely contiguous.

After VossELER, most workers, e.g., S t e p h e n s e n (1924), in this field considered that the young male specimens described as P. pacifica by S t r e e t s (1877, 1882) are actu ally of the present species. This annota­ tion sh o u ld be qualified since there is no female collelli found in the same expedition and the similarity of these young male sp ecim en s to the female, as m e n tio n e d by Streets, is co n firm ed by the obsevation of the pre­ sent investigation. With these considerations, P. pacifica (male only, S t r e e t s , log. cit.) is removed from the synonymy of the present species. D cdlich (1926) described a new species, P. gasli, from a mature male specimen collected from the adja­ cent waters of Naples. From the number of flagellar joints in the second pair of antennae, the length ratio of inner to outer ramus in uropod 2, and the shape of the carpus in peraeopod 5, it is in good agreement with the male collelli specimens from the Atlantic in the material of the present study. Since the characteristics of the male of this species are otherwise in full accordance with the descriptions

made by B o v a l l u s and V o s s e l e r , a repetitive description is therefore not desirable at this moment. It is also wise to remember that of the male specimens identified as P. collelli in the literature, a careful check might reveal that they may, in some cases, belong to either P. curuipes or P. pacifica. For instance, the seven­ teen mature male specimens taken by the Danish Oceanographical Expedition from the Mediterranean and

reported by S t e p h e n s e n (1924) as P. collelli are, with only one exception, found to be P. curuipes.

B ovallils (1889) has given a surprisingly large size, 12 to 18 mm, for this species. From the other records available in the literature, the size for the mature animals is 7.5 to 8.5 mm for the female and 7 to 7.5 mm for the male in the Atlantic (V o s s e l e r , 1901), 9 mm for the female and 8 mm for the male in the

eastern N. Atlantic and 7 mm for both sexes in the Mediterranean (S t e p h e n s e n , 1924) and 6 to 8 mm for the female in the Arabian Sea (B a r n a r d , 1937 b). In the present study, the largest size of the mature female is 10.8 mm, and the male, 8.5 mm.

Morphological Change with Growth. Among the genus Phronima, this species seems to have least modification of the form during the course of growth. This fact was noticed b y V o s s e l e r who remarked that the shape of the carpus of peraeopod 5 in young female specimens of the size of 3 mm already exhibited the specific characteristics. This is con­ firmed by the present study. Also, the inner ramus of the uropod 2, which is usually much shorter than the outer in the young stage among Phronima species, is found not to differ very much from the outer ramus even in very young stages. The shape of peraeopod 5 in the male is highly similar to that of the female. Although the length/width ratio of the carpus becomes larger when the male is mature, its general shape is still in good accordance with that of the female.

Geographical Variation. P.coUetti illustrates the most striking example of geographical variation among members of this family. Samples of specimens taken from the Indo-W. Pacific, eastern Atlantic and eastern Pacific are here com­ pared and several numerical characteristics are tested. The size of specimens from the Indo-W. Pacific is apparently smaller than those from the Atlantic or eastern Pacific. The female of the Indo-W. Pacific form reaches full maturity, i.e., with well developed ovaries and brood lamellae, at a very small size, usually at 6.5 mm, but not infrequently as small as 5.5 mm. The largest sized female found in this area is less than 9 mm. On the other hand the female of the Atlantic and E. Pacific forms has a larger size when mature. The mature females found in these two areas are never smal­ ler than 7.5 mm, and may be larger than 10.5 mm. The mature male of this species also varies in size: 6.1-7.3 mm in the Indo-W. Pacific, 7.1-8.5 in the Atlantic and 7.0-8.0 in the eastern Pacific. Specimens taken from different parts of the oceans not only differ in size but also exhibit certain morpho­ logical differences. V o s s e l e r ’s (1901) drawing represents the general form of mature females in the Atlantic. They have a very prominent crown, forming a strong convex curvature higher than the peraeon. The value of Hi is about 4, and P/A approximates to 1. Peraeopod 5 is strikingly short, shorter than the length of the peraeon. Its basos is at least one-fourth shorter than the bases of peraeopod 3. Its carpus is slightly shorter than one-fourth of its length. The crown of the females from eastern Pacific and Indo-W. Pacific is not so prominent, so that the dor­ sal profile of the head and peraeon seems to be confluent. Peraeopod 5 is short, as compared with that of other species, but is subequal to or slightly longer than the length of the peraeon. Its basos is definitely longer than that of peraeopod 3. However, the females from these two areas still differ from each other to a consider­ able degree. The values of Hj and P/A are 3-3Vz and nearly 1 respectively for the E. Pacific form and 3-3^2 and 0.90 for the Indo-W. Pacific form. The carpus of peraeopod 5 is, proportionalh’, about the same size as that of the Atlantic form for the Indo-W. Pacific form, but nearly one-third of the whole limb for the E. Pacific form. The male specimens from these three areas also show differentiated morphologj-. In the Atlantic form, the mature males have a 6-jointed flagellum in antenna 1 and 12-13-jointed flagellum in antenna 2. The crown of the head is not so prominent as in the female, but the value of Hh, more or less about 3 ^/2, is larger than that of the other forms. Peraeopod 5 has the most remarkably differentiated appearance in the At­ lantic form. The basos is wide, with a strongly convex anterior margin. The posterior margin of the merus, like that of P. pacifica, is strongly swollen to form a semicircular arc, the width almost subequal to the length. The proximal posterior corner of the carpus is produced upward, somewhat like that in P. pacifica, and the width/length ratio is subequal to or slightly larger than 1. The length of basos of peraeopod 5 is, again shorter than that of peraeopod 3. The Indo-W. Pacific form has only five flagellar joints in antenna 1, but with the same number of joints as the Atlantic form in the flagellum of antenna 2. The E. Pacific form has the antenna 1 similar to that of Indo-W. Pacific form, but has the flagellum of the second pair of antennae 15-17-jointed. The crown of the head in these two forms is normal and similar to each other. Peraeopod 5, unhke that of the Atlantic form, has a more or less straight anterior margin of the basos, which is longer than that of peraeopod 3, a globular merus apparently wider than long, and a carpus without the proximal posterior corner produced in both Fig. 5. The three forms of Phronimn collelti B o v a l l iu s . The lateral view of the adult and its carpus 5 and uropods. - Atlantic form: a-c. Female, 8.3 mm, Dana station 4000; d-f. Male, 7.1 mm, Dana station 4000. - Indo-W. Pacific form: g-i. Female, 8.2 mm, Dana station 3964; j-m. Male, 7.4 mm, Dana station 3893. ~ E. Pacific form: n-q. Female, 8.9 mm, Longlining station 2; r-t. Male, 8.0 mm, Longlining station 14. - (Scale, 1 mm. Carpus 5 and uropods are of the same magnitication). the Indo-W. Pacific and E. Pacific forms. The latter form is, however, different from the former in having the carpal process elongate and slightly bent forward. To demonstrate the morphological differences, a mature female and male of each of these three forms are illustrated in fig. 5 a-t. Several numerical characteristics of the females of these forms are compared and listed in Table 2. Each sample is composed of ten mature individuals and taken from one station or from stations that are close together. Table 2. The t-tests of means of several numerical characteristics among female specimens of Phronima coHetli from various parts of the oceans.

W. Pacific-Indian Atlantic

a 1) Atlantic...... 0.209 0.0694 3,01 •• Peraeon/Pleon b E. Pacific...... 0.066 0.0589 1.12 0.143 0.0539 2.65*

Atlantic...... 0.359 0.1543 2.33** Head length Length of Peraeon seg. 1-3 E. Pacific...... 0.024 0.0796 0.30 0.335 0.1596 2.10*

A tlantic...... 0.021 0.0745 0.28 Length of Peraon seg. 1-3 seg. 4-6 E. Pacific...... 0.093 0.0403 2.31* 0.084 0.0777 1.08

Atlantic...... 0.083 0.0621 1.34 7th Peraeion seg. 4-6th Peraeon seg. E. Pacific...... 0.046 0.0676 0.68 0.119 0.814 1.46

A tlantic...... 0.248 0.0717 3.46** Per, PI 1 E. Pacific...... 0.036 0.0704 0.51 0.284 0.0794 3.58*»

See the explanations under table 1 a.

Phronima affmis V o s s e l e r .

Phronima affinis. V o sse le r , 1901: 20, pi. 1, fig. 12-16 (original description of male; captures from Sargasso Sea; compared with male of P. sedentaria). St e p h e .v se n , 1924: 113 (in key). P irlo t, 1929: 112 (a specimen, possibly juve­ nile male, taken from waters between Azores and Madeira). Shih and D u n b .\r , 1963: test and fig. la and b (in key; identification).

Diagnosis. Male. TotaJ length of adult; 8 mm. H,j; 6; Hj: slightly smaller than 4. P/A: 0.93; PJj/Per,: 0.90. Antenna 1, well developed, flagellum 7-jointed; antenna 2, very rudimentary, which only a 2-jointed peduncle. Peraeopod 5, carpal process short, not prolonged to reach the ventral margin of the carpus; carpal tubercle low, without separate anterior tooth; metacarpus elongate, almost twice as long as the width of the carpus. The outer ramus subequal to the inner in all uropods.

Remarks.

V o s s e l e r recorded the only mature male specimen while P irlo t gave a doubtful record of a juvenile male specimen. The hyperiid amphipods from the Sargasso Sea where V o s s e l e r ’s type specimen was found have been reported since by S h o e .\i.\k er (1945) and G rice and H.\rt (1962). Neither of these authors found this species. The collection of the Dana Expeditions, which passed close to the locality where V o ss e l e r found his specimens, also did not provide any specimen that might be assigned to this species. The phroni- mids are generally considered to be cosmopolitan species and are recorded, though never found to be abundant, in most major oceanographic expeditions, yet not a single specimen of this species appears in this material; its validity is therefore questioned. The possibility of its being a synonym of P. sedentaria seems to be most probable on first examination. As has been mentioned earlier, this and P. sedentaria are the only two species among Phronima in which the antenna 2 of the male is rudimentary. The form of the carpus of peraeopod 5, also shown a signifcanl similarity between these two species. On the other hand, the separate anterior tooth of the carpal tubercle, although it may vary in size, is persistently present in P. sedentaria, but is absent in P. affinis. In addition to this dissimilarity, V o s s e l e r found that the posterior ventral margin of the carpus in peraeopods 1 and 2, which usually has a prolonged distal end in this genus, is not present in this species at all. The P/A ratio, which is measured from V o s s e l e r ’s figure, also provides a distinct character of this species from the other. It is always much larger than 1 for the mature male of the other Phronima species, but is slightly less than 1 for this species. Since V o s s e l e r ’s type specimen is not available for the present investigation, it is unjustifiable to give a determination for the systematic status of this species. Special attention has been paid to the observation of female Phronima specimens taken from the Sargasso Sea. They are how'ever found to belong to the known species only.

Phronima curvipes V o s s e l e r . Fig. 6 a-g.

Phronima curvipes. V osseler, 1901: 27-29, pi. 3, flg. 1-3 (original description; female; Atlantic). W alker, 1909: 50 (Indian Ocean). Stephensen, 1924: 126-127, flg. 53, chart 17 (in key; capture and vertical distribution of the Medi­ terranean and Atlantic; known records in literature). Mogk, 1927a: flg. 31 (carpus 5 illustrated); 1927b: 137-139, flg. 6 (propagation; flnding of young males; S. and N. Atlantic). P irlot, 1929: 114 (Atlantic Morocco coast). B arnard, 1932: 285 (S. and N. Atlantic). R eid , 1955: 20 (Atlantic off W. Africa). Shih and D unbar, 1963, text, flg. 4 a and b (in key; identification; bibliography; world distribution, with special reference to I.C.E.S. area). Phronima coUeili. Steph en sen , 1924: 126 (misidentifled, part of the males only; Mediterranean).

Diagnosis. Female. Total length of adult: 8.5-17 mm. H^: 6- 6V3; Hi: P/A: 0.90 ±0.05; Plj/Per,: 0.70 ±0.06. Perae- opod 5, basos in reversed “S” shape, a strong process pointed backward at the distal end of posterior margin; merus, globular form, longer than wide; carpus, longer than wide, except the rounded dorsal third, the posterior margin parallel with the anterior, carpal process strong and protruded downward, carpal tubercle strong and single, with 6-7 tooth-like projections; metacarpus, longer than the width of the carpus, with weak metacarpal tubercle. Uropod 2, inner ramus at least one-fourth shorter than the outer. Male. Total length of adult: 6.0-9.2 mm. H^: 5V2- 6 ; Hj: 3- 3V2- P/A: 1.08±0.08; Plj/Per,: 0.92±0.07. Antenna 1, well developed, flagellum 6-jointed, 1st flagellar joint subequal to two-thirds of head height; antenna 2 , well developed, subequal to the length of antenna 1, flagellum 7-9-]ointed. Peraeopod 5, posterior margin of basos slightly curved as that of the female, but in slight degree; merus, slightly wider than long, posterior margin semicircular in the dorsal two-thirds and oblique in the ventral one-third; carpus, wider than long, proximal posterior corner highly produced, against the oblique posterior margin of merus, carpal process moderate, and slightly bent backward, carpal tubercle with a separate anterior tooth and 4-5 closely contiguous tooth-like projections. Outer ramus at least one-half longer than the inner ramus in uropod 2.

Remarks.

This species was not reported in the literature until V o s s e l e r ’s work was published. The reversed “S” curvature of the basos of peraeopod 5 forms the most distinctive character by which to recognise the female. The carpus of this peraeopod is thick and similar to that of P. solitaria to a high degree. The crown of this species is well developed, but unlike that of P. coUetti, is confluent with the dorsal profile of the peraeon. The peraeon segment 7 is elongate, usually longer than the three preceeding segments together, and always longer than one-thrid of the pleon segment 1.

The only record of the male of this species is reported by M ogk (1927 b) who found some young male specimens from the Gauss collection. He mentioned that these young males resemble the females of similar size in the form of the head, the expansion of the posterior part of the carpus and the dentition of the carpal tubercle of peraeopod 5. These young specimens were found in the Atlantic off western Africa (12°11' S, 6°16' W and 0°46' X, 18°50'W), where many male specimens are also found in the present investigation (Dana Stations 3998 and 4000).

S t e p h e n s e n (1924) found 99 female specimens of this species from the Mediterranean but failed to discover the male in the same collection. In his report, however, he recorded more male specimens than females of P. coUetti from the Mediterranean. A re-identification of his Mediterranean male coUetti specimens has revealed that these in fact are mostly of the present species (curvipes). Description of Male. (Fig. 6 g-q).

Apart from the above brief remark made by M ogk, the male of this species has never been described. VossELER (1901) presumed that it might be similar to the type of male P. atlantica. The following description is based on specimens taken from the Atlantic Ocean (Dana Station 3998). Head, height in length 2^/3, frontal surface flat, with a ridge elevated between the frontal and lateral surface. Lower group of eye facets well developed, centered at the lower ^/j(, of the lateral surface. Antenna 1, inserted on the frontal surface at the lower of the head height, medial to the lower eye faccts, 1st flagellate joint 2/3 of head height and about twice the length of the remainder of the flagellum; antenna 2, inserted on the frontal surface at the lower V4 the head height, medial to the anterior ventral corner of the inferior eye facets, flagellum about the length of the first pair of antenna, with 7-9 joints. Peraeopods, First; basos, width about of length, anterior margin straight, posterior margin slightly convex, length about ^/3 longer than the next 3 joints together; ischium, longer than wide; carpus, distal posterior margin produced downward, with the ventral margin serrated; metacarpus, slightly longer than carpus; dactylos, narrow, about V3 of metacarpus. Second: basos, longer than that of the first and V4 longer than the next 3 joints together; otherwise, similar to the first. Third: basos, ‘‘/j longer than that of the first, anterior and posterior margins more or less straight and parallel, with a tiny seta inserted at the distal end of the posterior margin; length of the next 4 joints in basos, */9. “/s. Vs respectively, posterior margin with few setae in merus, but finely serrated in carpus and metacarpus. Fourth: basos, almost 2 in that of the first; otherwise, similar to the third. Fifth: basos, subequal to that of the third, anterior margin dilated at lower one-third, posterior margin slightly curved in reversed “S” shape, with the blunt distal process pointed backward; ischium, in basos, merus, subequal to length of ischium, slightly wider than long, anterior margin straight, posterior margin semi-circular on the dorsal two-thirds, and obhque in the remainder; carpus, 2/3 in basos, width about larger than length, anterior margin oblique anteriorly, with the carpal process slightly bent down­ ward, proximal posterior portion highly humped, carpal tubercle with one separate anterior tooth and 4 contiguous tooth-like projections; metacarpus subequal to the length of ventral margin. Sixth: basos, ’/g of that of the fifth, and 1/7 longer than the next 3 joints together; ischium, posterior margin concave, anterior margin convex and pointed at the centre; carpus longer than 2 in merus and Va longer than metacarpus. Seventh: basos, subequal to tliat of the fifth and 1/2 longer than the next 3 joints together, otherwise, similar to the sixth. Pleon, V5 shorter than peraeon. Epimeral plates most developed in the second pleon segment, ventral margin of the first segment only slightly concave. Urus, subequal to the pleon segment 3, the coalesced segments longer than one-half of the first urus segment. Uropods, lateral and medial margins parallel; outer ramus subequal to the Inner in uropods 1 and 3, but twice as long as the inner in uropod 2; length ratio of peduncles: 15:10:12; length ratios of outer ramus to the peduncle: ®/g, and

Discrimination of Males of P. curvipes, coUetti and pacifica. Males of these three species can be distinguished, as already mentioned, by the number of joints in the flagellate part of antenna 2, the shape of merus and carpus in peraeopod 5 and the length ratio of outer to inner ramus of uropod 2. In addition, several numerical characteristics were tested between every pair of the species. To each pair, three characters, which are scattered over the body, were then selected to fit in the

discriminant function (S t a n l e y , 1962). To carry out these tests, a sample of ten mature specimens of each of the three species was taken randomly from a single station: P. curvipes and P. pacifica from Dana Station 3998, and P. coUetti from Dana Station 4000. The F test of the analysis of variance of each of the three pairs was significantly high, and led to the conclusion that these three species are discriminant from each other. The statistical data are summarized in Appendix table 1.

Morphological Change with Growth.

Female specimens of this species of 6 mm or less in length can be recognised by the well developed crown of the head. The basos of peraeopod 5 is straight at this stage, but the blunt process at the distal end of the posterior margin already shows the specific characteristic. The carpus of this peraeopod is rather thick, as compared with those of other species, in these young animals, and the carpal tubercle is bifid. Specimens of 7-8 mm already show the trace of reversed “S” curvature in the basos of peraeopod 5, but only to a very slight extent. The dorsal margin of the metacarpus, peraeopod 5, swells but without projections. When the female approaches sexual maturity, it aslo acquires the remarkable specific characteristics: the strongly reversed “S” shape of the basos, the single carpal tubercle and the metacarpus with projections in peraeopod

5, and the elongate peraeon segment 7 (fig. 6 a-f). Fig. 6. Phronima curvipes V o s s e l e r , the female peraeopod 5 and the male form. - Female; a. Dorsal contour of the head and peraeon of a young female, 6.1 mm; Peroaeopod 5: b. 6.1 (total body length in mm); c. 7.4; d. 8.8; e. 13.3 and f. 16.8. - Male: g. Lateral view of the adult, 6,9 mm, Dana station 3998; h-p. Peraeopods 1-7 and q. Uropod of the same. - (Scale, 1 mm. Peraeopods and uropods of the male form are of the magnification).

The young male is very similar to the female of approximately the same size, as observed by Mogk (1927 b). When they reach the penultimate stage, the male characteristics gradually appear, e.g., the dilation of merus and carpus in peraeopod 5.

Geographical Variation. This species, unlike P. coUetti, seems to have no significant geographical variation, although the size of mature individuals is generally larger in the Atlantic than in the Indo-W. Pacific. Only a few young speci­ mens are available from the E. Pacific area. Phronima stebbingi Vo s s e l e r . Fig. 7 a-d.

Phronima stebbingi. Vosseler, 1901: 36-39, pi. 4, fig. 4-10 (original description of male and female; Atlantic). Chev- REUX, 1913: 5, flg. (Mediterranean off Monaco). Stewart, 1913: 254 (S. Atlantic). Stephensen, 1924: 113 (in key). Chevreux and Fage, 1925: 397, fig. 399 (after Vosseler, 1901) (in key; description; distribution). Mogk, 1927b: 133-137, fig. 4, 5 (captures and known records in Atlantic and Indian Oceans; morphology). P irlot, 1929: 115-116 (synonymy; diagnosis; adjacent seas of Madeira). Chevreux, 1935: 186-187 (N. Atlantic). Shoemaker, 1945: 236 (adjacent waters of Bermuda). R eid, 1955: 20-21 (Atlantic off W. Africa). H urley, 1956: 17 (deep Californian waters). Irie, 1958: 142, 143 (listed; Tsushima Current); 1959: tab. 4 (listed; adjacent seas of Japan). H urley, 1960a: 280 (S. Pacific). E vans, 1961: 232 (listed; Equatorial Atlantic). Grice and H art, 1962: 301, appendix tab. 3 (listed; Atlantic between New York and Bermuda). Vinogradov, 1962: 23 (S. Pacific-Indian). Shih and Dunbar, 1963: text and flg. 8a-d (in key; identification; bibliography; world distribution). Phronima paciftca. St e b b in g , 1888: 1348, pi. 159 (misidentifled; Atlantic). B o v a lliu s, 1889: 382-385, pi. 16, fig. 48-50 (misidentifled; description of male).

Diagnosis. Female. Total length of adult: 6.0-9.0 mm. H^: 6V4- 7 ; Hj: P/A: 1.17 ±0.08 (for Atlantic form only); Plj/Per,: 1.15 ±0.05 (for Atlantic form only). Peraeopod 5, similar to that of P. o//on/ico, with a blunt process at the distal end of posterior margin of basos; carpal subtriangular, carpal tubercle bifld; metacarpus longer than the ventral margin of carpus. Pleon segment 1 apparently longer than peraeon segment 7. Uropod 2, outer ramus much longer than inner ramus. ■ Male. Total length of adult: S.5-7.6 mm. H^: 6V4- 6V2; Hj: P/A: 1.27 ±0.06 (for Atlantic form only); Pli/Per,: 1.25 = 0.08 (for Atlantic form only). Antenna 1, well developed, flagellum 7-jointed, 1st flagellate joint about */, of head height; antenna 2, well developed, flagellum 10-12-jointed. Peraeopod 5, similar to that of the female, but width of carpus subequal to length. Pleon segment 1 apparently longer than peraeon segment 7. Uropod 2, outer ramus much longer than the inner.

Remarks. The most remarkable characteristic of this species is the comparatively short peraeon, especially peraeon segment 7, which is usually longer than pleon segment 1 in other Phronima species. Otherwise, this species, either female or male, is strikingly sim'lar in general appearance to P. atlantica. This resemblance is most clearly exhibited in the form of peraeopod 5.

Morphological Change with Growth.

M ogk (1927 b) studied the morphology of this species, based on material collected from the Atlantic. He noticed the great similarity between the male and female of the same size in the length proportion of peraeon to pleon. Although this is not confirmed in the present study, it is found that before reaching maturity, the sexes resemble each other to a much greater degree than in other species. When the animal approaches maturity, the carpus of peraeopod 5 becomes narrow in the female but widened in the male. These opposing trends form the most contrasting morphological change between the two sexes.

Geographical Variation. Not many specimens of this species are found from the Indo-\V. Pacific area. In the specimens taken from x\tlantic and E. Pacific areas certain differences are found. la the E. Pacific form, the difference of length between the pleon segment 1 and peraeon segment 7 is samller than that in the Atlantic form, e.g., Pli/Per, for the E. Pacific form: 1.06 (female), l.lo (male); Atlantic form: 1.15 (female) and 1.25 (male). In peraeopod 5, the E. Pacific form has a longer process at the distal end of the posterior margin of the basos. The length/ width ratio of the carpus of this peraeopod is larger than ’/a in the female E. Pacific from while smaller than ®/4 in the female Atlantic form. This difference of length/width ratio is not present in the male. The flagellate part of the second pair of antennae in the male is 10- to 11-jointed in the E. Pacific form but 11- to 1 2 -jointed in the x\tlantic form. Fig. 7 shows the females and males of both forms. Fig. 7. Two forms of Phronima stebbingi V o s s e l e h . - E. Pacific form: a. Female, 9.3 mm, Longlining station 14; b. Male, 7.3 mm, Long- linig station 14. - Atlantic form: c. Female, 7.3 mm, Dana station 3998; d. Male, 6.4 mm, Dana station 3998.

Genus Phronimella C la u s.

Phronimella. Cla u s, 1872b: 467 (brief diagnosis); 1879: 64 (more detailed diagnosis). St r e e t s , 1882: 7 (revision). S t e b b in g , 1888, P t. 1 (literature survey); P t. 2: 1361 (diagnosis). B o v a lliu s, 1889: 341, 386-388 (in key; diagnosis, synonymy; literature survey). Ch e v r e u x and F a g e , 1925: 399 (in key; brief diagnosis). P ir l o t , 1929: 116 (diagnosis). Anchylonyx. St r e e t s , 1877: 130-131 (original description).

Claus’ original definition for the genus is incomplete and partly not correct. The following diagnosis is adapted from Ch e v r e u .\ and F age (1925) and P ir lo t (1929) with additions: Head moderately high and conical; outer plate of maxilla 1 provided with strong and isolated denticles; body slender and transparent; peraeon segments lower than head; the first two segments partially coalesced on the dorsal portion; higher than the following segments; the remainder of segments free from each other, subequal in height; peraeopods slender, peraeopods 3 (the longest of all) and 4 filamentous with spinous processes on the posterior margin of the basos; peraeopod 5. with spinous processes on the anterior margin of basos, ischium, merus and carpus, the latter, narrow, together with metacarpus forming an imperfect folding hand; the last two urus segments coalesced; uropods 1 and 3 normal, with a styliform peduncle and two sharp-pointed rami; uropod 2, reduced to form a tiny pointed process in the female, and usually normally present but small in the male.

Phronimella elongata C laus. Fig. 8 a-f,

Phronima elongata. C la u s , 1862a: 193-195, pi. 19, fig. 2, 3, 7 (original description of female); 1862b: 247, pi. 3, fig. 6-11 (description of male). Phronimella elongata. Cl a u s, 1871: 149 (assigned the new generic name without diagnosis). Ca r u s , 1885, 423 (listed: Mediterranean). Ch u n , 1887: 29 (Mediterranean). St e b b in g , 1888: 1362-1369, pi. 163 (detailed description of male and female specimens from various localities of Pacific and Atlantic). B o v a l l iu s, 1889: 389-395, pi. 16, fig. 52-67 (diagnosis; synonymy; literature survey; detailed description of male and female). Ch u n , 1889: 531 (adjacent seas of Canary Islands). Ch e v r e u x , 1900: 138 (captures from N. Atlantic). V o sse l e r , 1901: 40-42, text fig. (description; Atlantic); 1903 (in Lo B ianco, 1903): 278 (listed; Naples). Lo B ia n c o , 1909: 596 (breeding season). W a l k e r , 1909: 51 (Indian Ocean between Madagascar and Maldive Archipelago). St e u e r , 1911: 673 (Adriatic Sea). P e s t a , 1920: 30 (Adriatic Sea). S p a n d l , 1924b: 265 (abundant in Adratic Sea). St e p h e n s e n , 1924: 130-134, chart 19 (Mediterranean and Atlantic; vertical distribution, size and propagation in the Mediterranean; world distribution). Chevrelx and Page, 1925: 399, fig. 400 (description; Mediterranean and Atlantic). Bigelow, 1926 (S.W. of Georges Bank). Mogk, 1927b: 141-144, fig. 9-11 (captures and known records in Atlantic^and Indian Oceans; distribution; size and age). B.A.RNARD, 1930: 43-44 (N. Atlantic; adjacent waters of Three Kings Islands, S.Pacific). Pirlot, 1930a: 116-117 (syno­ nymy; distinctive characters; distribution; captures from eastern X. Atlantic); 1930b: 15-16 (adjacent seas of Indo- Australian Archipelago). Barnard, 1932: 286 (morphological transformation of male; breeding season; N. Atlantic). Chevreux, 1935: 187 (N. Atlantic). Barnard, 1937b: 186-187 (Arabian Sea); 1940: 484-485 (listed; Durban, Africa). Shoemaker, 1945: 236, 238 (synonymy; distribution; the adjacent waters of Bermuda). H itrley, 1955: 165, 170 (in key). R eid, 1955: 21-22 (Atlantic off W. Africa). Irie, 1958: 142, 143 (listed; Tsushima Current); 1959: tab. 4 (listed; adjacent seas of Japan). H urley, 1960a: 280 (S. Pacific). Evans, 1961: 232 (listed; Equatorial Atlantic). Grice and H art, 1962: appendix tab. 3 (listed; Atlantic between New York and Bermuda). Shih and Dunbar, 1963: text and fig. 9a-d (in key; identification; bibliography; distribution, with special reference to I.C.E.S. area). Siegfried, 1963: 9 (listed; Atlantic off S.W. Africa). Anochylonyx hamatus. Streets, 1877: 131-132 (original description; N. Pacific). Phronimella ftliformis. Bovallius, 1887: 26 (original description; S. Atlantic). Phronimella hippocephala. Giles, 1887: 217, pi. 3, fig. 3 (original description; Bay of Bengal).

Diagnosis. Female. Total length of adult: 9-20 mm. H^: 4Vj-5V2; Hj: 21/2-3. P/A: 1.02 ±0.07; P\JPer,: 1.00-0.12. Perae- opod 3, longer than any peraeopod, with 2-3 spinous processes at the posterior margin of basos; metacarpus, longer than basos, straight, filamentous and tapering distally. Peareopod 5, basos, subequal to the next 3 joints together, with 5 to 6 spinous processes on the anterior margin; carpus, narrow and slightly dilated at distal portion, with 5 to 6 spinous processes on the anterior margin, carpal process short, ventral margin of the carpus with 3 separate teeth. Uropod 2, represented by a very tiny process only. Male. Total length of adult: 7.5-12 mm. H^: 4i/j-5; Hj: P/A: 1.12 ±0.07; Plj/Per,: 1.16 ±0.11. Antenna 1, well developed, flagellum 14-16-jointed, 1st fagellar joint longer than of head height and slightly shorter than the next 5 joints together; antenna 2, well developed, shorter than antenna 1, flagellum 14-16-jointed. Peraeopod 3, longer than any peraeopod, basos without spinous processes on the posterior margin, about in length of metacarpus. Peraeopod 4, with 3 to 4 spinous processes on the posterior margin of the basos. Peraeopod 5, basos about ^/jq shorter than the next 3 joints together, anterior margin with spinous processes; carpus, narrow with 3 to 4 spinous processes on the anterior margin, carpal process short, two separate teeth on the ventral margin of carpus. Uropod 2, short and narrow, inner ramus at most of the outer.

Remarks. The general form of this species is similar to that of the Phronima species, e.g., the shape of head, peraeon and pleon, the structure and distribution of the superior and inferior groups of eye facets, and the insertion of the antennae on the lower frontal surface. The peraeopods, on the contrary, provide distinctive characters. They are slender, and in certain segments filamentous, with a spinous border in some pairs.

Uropod 2 is usually described as disappearing in the female (fig. 8 a and b) and reduced in the male

(fig. 8 c arid d) but this requires qualification. In the female, the remnant of uropod 2 is represented by a small pointed process. This process does not increase proportionally w ith the increase of size. In the male, it is only a small process in the very young stages (fig. 8 e), then becomes a peduncle with an outer ramus, with the inner ramus obscure or small. In the adult male, while uropod 2 is small as compared with the other two pairs of uropods, it is usually clearly visible. It is however not uncommon to find among the adult males, some that have uropod 2 represented only by a small process (fig. 8 f) as is found in the female. Since this reduction of orupod 2 in the male occurs randomly in the samples, it is considered only to be an indi­ vidual variation, as no other morphological differences are detectable between specimens with normal or reduced uropod 2 .

Morphological Change with Growth. This species shows only a slight change of form during the course of growth; several proportions of body parts do not change significantly, including Hh, Hj, P/A and Pli/Per,. ■Y/7 i // " \\ \

Fig. 8. Phronimella elongata C l a l s . - Female: a. Lateral view of the adult, 11.0 mm, Dana station 3689; b. Uropods of the same. - Male: c. Lateral view of the adult, 8.6 mm, Dana station 3689; d. Uropod of the same; e. Uropods of a young male, 5.4 mm, and f. Uropods of an adult with rudimentary antenna 2, 8.8 mm.

Geographical Variation. The fragility of this species accounts for the very badly preserved condition of the specimens. Because of this, it is very difficult to make detailed observations in order to compare morphological characteristics of specimens from different geographical areas. III. LIFE HISTORY Development and Growth

Among the amphipods, Gammariis chevreuxi is perhaps the one that has been most fully observed during the course of its growth. S exto n (1924) has recorded that certain characters can be used as indicators of growth stages such as the antennae, the gnathopods, the setae and spines. Of these characters, the first pair of antennae is of particular importance because an e.xamination of its primary flagellum would tell pre­ cisely the moulting stage, or number of instars, of the animal. According to S ex to n , the proximal joint of the primary flagellum in this antenna is the part responsible for the increase of joint number. In every moult, the proximal joint is divided into two joints, of which the distal one is elongate and subdivided again into two. Only the distal of the last two joints bears a along seta at its distal end. Apparently in every moult two new joints of different characteristics are derived from the proximal joint of the flagellum. A count of the alternating flagellar joints, characterized by the presence or absence of the distal seta, will therefore indicate the number of moults that the animal has passed through. In hyperiid amphipods, unfortunately, no comparable observation on living material throughout the life span has been made. M ogk’s (1926, 1927 a) “Versuch einer Formanalyse bei Hyperiden” possibly is the most comprehensive study that has ever been made to relate the change of forms with growth, based on preserved specimens. His work dealt mainly with two species of Phronima, P. sedentaria and P. atlantica, and he was able to tell the instar number by the shape of the head, by the shape of the carpus of peraeopod 5, and by various proportions of body parts from which he has constructed many curves in his paper. K ane (1963 a, 1963 b), working on two hyperiid species, Paralhemisto gaudichaudii and P. gracilipes, found the pleopod podomere to be a good indicator of development stage. She was able to relate the increase of podomeres in the pleopods to the increase of the body size in the living and preserved materials of P. gaudichaudii in the juvenile period. The animals of this group are divided into nine stages, the podomere number in the exopodite of the first pleopod increasing from one in the 1st stage to nine in the 9th stage. At the same time, the growing animals develop some new characters that are different from the previous stage. Owing to the constancy of the increase in size and of the development of new characters between each of these stages, she suggested that the change from one stage to the next is accomplished by the moulting, during which a podomere is added to the exopodite of the next stage. Since the number of podomeres in the endopodite of the pleopods is not usually equal to that in the exopodite of the same pleopod (there may be differences of two or more), she suggested that there might be intermediate stages. If intermediate stages do exist, the stage she described might represent more than one moult. In the present investigation, it is found that the podomere number in the pleopods is closely related to the form and size of the specimens, especially in the young stages. It is therefore believed that it might be a reliable indicator of the stages, probably also of the instar numbers, of the animal. In the phronimid hy- periids, the podomere number is equal in both of the rami of the same pleopod in the early stages. It is then one fewer in the endopodite than in the exopodite in the following stages. The difference becomes larger and larger in the maturing specimens. Kane (1963 b) found an unequal number of podomeres in different pleo­ pods of Paralhemisto gracilipes. It is noted in the present study that, in the young individuals, all three pleo­ pods of the same specimen have the same podomere number. In the mature individuals, however, pleopod 1 in some cases may have one less than pleopod 3. The podomere number in pleopod 3 is used consistently in the present study. The following description of the developing stages, using podomere number as an indicator, is based mainly on observations made on P. sedentaria, the best known species of the family. These stages, in terms of sexual development, are further grouped into four periods: juvenile, immature, adolescent and mature. For the other specics, a tabulated form of this relationship will be given subsequently.

Prehatching (Fig. 9 a and b). The animal curls within the egg membrane. The size is 0.25 to 0.30 mm in diameter, but about 0.45 mm when straightened. A mass of egg yolk is present ventral to the body. Antenna 1 is knob-like. All peraeopods appear almost of the same size and shape, with the first two pairs slightly longer than the remainder. Pleon and urosome are poorly developed. Pleopods and uropods are seen as stump-like projections, without any trace of rami. Branchial pouches are not developed. Specimens of this stage are always found inside the brood pouch of the female.

Juvenile Period. In this period, it is not possible to distinguish the sexes. The animals are found living within the brood pouch of the female or inside the barrel of a tunicate. The general characteristics of the animals at this period are highly elevated position of the head, the backw ard-extended midgut, the small pleon and urosome, the simplicity of the appendages and the thin transparent exoskeleton. This period includes Stages 1 to 3.

Stage 1. (Fig. 9 c and d). The animal is free of egg membrane, but still more or less circular in shape. The size, when straightened, is O.oo to 0.65 mm. Antenna 1 is undifferentiated. The general structure of the peraeopods shows no development. How­ ever, that they are of two groups is becoming apparent by the opposite bending direction between basos and ischium. The pleopods possess two blunt, spineless processess at the distal end of the peduncle but not separa­ ted from it. Uropods are still simple. The midgut extends to the 6th peraeon segment and is filled with egg yolk. Three pairs of branchial pouches, each posterior to the peraeopods 4 to 6, are visible though small. Specimens of this stage are carried within the brood pouch of the female.

Stage 2. (Fig. 9 e~g). The animal is somewhat straightened in shape. The size varies between 0.9 and 1.6 mm. Antenna 1 has been differentiated into two joints. The peraeopods, except for the fifth pair, show' more or less the normal pattern in the later stages, i.e., with the ischium turning forward in the first four pairs and backward in the last two and the turning downward of the metacarpus in all of them. Peraeopod 5, shorter than any other, is straight. Its carpus, although somewhat dilated, does not show any indication of becoming differentiated toward a subchelate hand. Pleon and urosome together are subequal to the length of the last two peraeon segments. The rami of the pleopods are elongate, with a very narrow distal end. This is the first indication of segmentation in the rami. Uropods are bilobed at the distal end. The differentiation of the rami from the peduncle in the uropods is therefore incomplete. The midgut extends to the end of the 4th peraeon segment and is empty. Specimens of this stage, although in some cases carried in the brood pouch of the female, more often are found inside the tunicate barrels or free in the samples. The fact that they are scattered in the sample must not be considered as evidence for the start of a free life, since they might be stimulated and escape from their shelter (either the brood chamber or the tunicate barrel) when the fixative is added to the sample. The transparent and empty midgut at least suggests that at this stage they have not yet started to feed them­ selves. Fig. 9. Early stages of Phronima sedenlaria F o rs k a l. - Prehatching: a. Peroaeopods and b. Uropods. - Juvenile period; Stage 1: c. Lateral view and d. Uropods; Stage 2: e. Lateral view, f. Uropods and g. Pleopod 3; Stage 3: h. Lateral view, i. Uropods and j. Pleo- pod 3. - Immature period; Stage 4; Lateral view of male (k) and female (m).

Stage 3. (Fig. 9 h-j). The size of the animal is from 2.2 to 3.2 mm. The peraeon segments, except for the first two, are subequal in length. The peraeopods are much more highly differentiated than in the previous stage. The carpus of peraeopod 5 develops a small carpal process. Peraeopod 7 has an extremely elongate basos, which alone is almost equal to the length of the whole peraeopod 5. Pleon and urosome have lengthened sligtly. Both rami of the pleopods have two podomeres, each provided with a pair of distal spines. The distal podomere is small and apparently is formed from the narrow distal end of the previous stage. Although the rami of the uropods have become elongated they seem to be continuous with the peduncle. The distal ends of the rami are rounded. The midgut extends to the an­ terior half of the 4th peraeon segment. Dissection has shown that some of the specimens contain diatom shells in the midgut. This is possibly the first stage in which the animal starts to feed. Specimens of this stage are usually found within the tunicate barrels or free in the samples. It seems at this stage that the animal is ready to be independent of the maternal care.

Immature Period. The sexual dilTerences are recognizable at this period, but the gonads are poorly developed. The external features of the female and male, except for the presence of the much more well-developed antenna 1 in the latter, are almost identical in specimens of similar size. Unlike the previous period, the animal no longer depends on the mother or the tunicate barrel. The raised head has gradually become perpendicular to the longitudinal axis of the body as in the adult form. The exoskeleton is thicker and paler than in the previous period. The specific characteristics have gradually appeared, though not perfected. In this period, the male passes through two stages (stages 4-5) and the female nine stages (4-12). Stage 4 - Fem ale an d Male. (Fig. 9j and k). The head is only slightly elevated. The distal joint of antenna 1 is provided with sensory hairs. The eye facets are well developed. In peraeopod 5, the carpal tubercle is present, the metacarpus elongates and lies closely against the carpus. Pleon and urosome have increased markedly in length. The two parts together, including the uropods, are subequal to the length of the peraeon. Both rami of pleopods have three podo- meres, each with a pair of distal spines. The addition of new podomeres in the pleopod is apparently derived from the distal end of the proximal podomere. This is in agreement with Sexton (1924) who stated that the direction of growth takes place at the proximal end of an organ and not the distal. Uropods are well differ­ entiated; rami of the uropods are well demarcated from the peduncle and possess pointed distal ends. The greatest change at this stage is the development of sexual dimorphism. The first pair of antennae is thicker in the male than in the female, but with no difference in length. These antennae, both in the female and male, show an external structure of two joints. The inner tissue in the distal joint of the male antennae exhibits, however, an incomplete segmentation. This demonstrates that the two joints of antenna 1 in the female are formed of two parts; the proximal joint is analogous to the 3-jointed peduncle in the male, and the distal joint to the many-jointed flagellum of the latter. Besides the difference in the first pair of antennae, from the specimens available for the present study, the size difference between the female and male is already present: 3.5 to 4.5 mm for the male and 4.0 to 5.0 mm for the female. The reproductive organs are rudi­ mentary; the ducts especially are hardly visible. Specimens of this stage are always found free in the samples. Judging from the advanced development of the appendages, especially the pleopods, they seem able to manage their lives w ell and will no more inhabit the tunicate barrels. Stage 5 - Male. The head is perpendicular to the longitudinal axis of the body. The peduncle of antenna 1 is 3-jointed. The llagellum of this pair of antennae, although not many-jointed at this stage, has increased considerably in size. In the last stage it is only about twice the length of the peduncle but at this stage is at least three times the length of the latter. The inner tissue at the distal part of the flagellum shows some incomplete seg­ mentation. The pleopods have five podomeres in the exopodite, four in the endopodite. Testes are much more developed and the vasa deferentia can be traced to their openings at the median part of the sternum between the bases of the last pair of peraeopods. The size of specimens at this stage varies from 5.0 to 6.5 mm. Stages 5-12 - Female. The female, unlike the male, passes the immature period in eight stages and reaches a much larger size at the end of this period. There is no abrupt change during this period. The proportions of body parts are approaching the specific values, but the general shape of the body is slim. The musculature develops slowly. The most important character, however, is seen in the development of the gonad. The ovaries are a pair of small pocket-like structures lying on the dorsal surface of the midgut. They contain a mass of small cells. The oviducts are very fine and delicate, and it is difficult to trace their course to the opening at the base of peraeopod 6. Xo ooste- gites are developed. The size of the specimens at these stages varies from 6.0 to 25.0 mm. The number of podomeres in the exopodite and endopodite of the pleopods increases from six to seventeen in the former and from five to fourteen in the latter. The detailed sizes and podomere numbers of each stage are listed in Table 3.

Adolescent Period. The animal continues its increase in size, but more importantly, there is a further development of the gonads and other secondary sexual characteristics. The male passes through this period in one stage while the female seems to take two. Stage 6 - Male. The flagellum of antenna 1 becomes more elongate. In addition to the 1st flagellar joint, there may be three or four small joints at the distal end. The inner tissue at this stage however usually shows complete segmenta­ tion of the distal joints, i.e., excluding the 1st joint, there are six in number. These distal joints are all very short as compared with the mature specimen. The testes and vasa deferentia are very well developed. The latter have a swollen portion, the seminal vesicle, before they turn medially. The body has become thicker. There are seven podomeres in the exopodite of the pleopods and six in the endopodite. Occasionally there are a few specimens which have eight podomeres in the exopodite and seven in the endopodite, but without a size difference (fig. 11). It is therefore presumed that there is only one stage in the adolescent period. The size range for the specimens of this stage is from 7.0 to 8.5 mm. S tages 1 3-1 4 - F em ale. The most apparent characteristic of this stage in the female is the development of oostegites, four pairs of thin sac-like structures, each inserted medially at the base of peraeopods 2 to 5. The ovaries increase in size and extend posteriorly. The oocytes become larger, but adhere to one another. The oviducts are thick and open at the base of the last pair of oostegites. The size of the specimens at these stages varies from 22 to 30 mm. The podomere number of the pleopods is 18 to 19 in the exopodite and 15 to 16 in the endopodite.

Mature Period. The gonads and the secondary sexual characters are perfectly developed at this period. Stages 7-8 - Male. Seven joints are completely formed in the flagellum of the first pair of antennae. The first flagellar joint becomes very thick and is provided with dense fine hairs. The body shape is greatly changed from the previous stage. This is particularly prominent in the pleon, where the dorsal margin becomes heavily undulated, the epimeral plate is well developed, and the peduncles of the pleopods change from oblong in the previous stage to a heart-like form. The musculature is highly developed in the peduncle part of the pleopods and in the pleon which connects the latter with the pleopod peduncles. This highly developed musculature pre­ sumably plays an important role in the animal’s activitj* at this period. The male is likely to go through two stages during this period. Stage 7 is much more common than stage 8. The former varies in size from 8.0 to 9.0 mm, with eight and nine podomeres in the pleopod endopodite and exopodite respectively. The podomere number in the specimens of stage 8 is one more than in the previous stage. The size is usually larger than 8.6 mm. S tage 15++-Female. The external features of the female at this period do not change much from those of the previous stage. The ovaries have, however, developed to the highest degree. The oocytes are large and separated from each

Dana-Report No. 74, 1969 6 other. In the fuHy mature individual, there may be more than 200 fully developed egg cells in each ovary, e oostegites are ^vell developed. They elongate and broaden and finally meet ventrally with those of the opposite side to form the brood pouch. It seems that the formation of the brood pouch is synchronized with the ejection of the eggs “ The f * niale at this period is likely to pass through more than one stage. How ever, since the size and podo- mere 'ariations are large and few data are available, it is not feasible to judge the number of stages from e preser^ed specimens. The size of the animal at this period varies from 25 mm up to 42 mm. The podo- mere number changes from 20 to 26 in the exopodite and from 17 to 21 in the endopodite. periods and the stages of the development and growth of P. sedentaria are listed in Table 3; for the o or species of this family, in table 4. Figures 10 and 11 show the length frequencies of the female, including the sexuall\ indistinct juvenile, and the male specimens of P. sedentaria taken from Dana Stations 4017—4019, plotted against the podomere number of the pleopod 3. Hauls from these stations are especially suitable for t is purpose, since thev not onlv are rich in number of specimens but also contain various sizes of the individuals of P. sedentaria. “ From Figues 10 and 11 and table 3, it is apparent that, in P. sedentaria, the early stages during develop­ ment are clearly indicated by the podomere number. This is particularly true in the juvenile and immature periods, in which specimens possessing the same number of podomeres in the pleopod rami not only aggre-

Table 3. The periods and stages of the development and growth of P. sedentaria, based on the development of reproductive organs and secondary sexual characteristics and the podomere number in the pleopod rami. Samples taken from Dana Stations 4017-4019.

Period Characteristic Stage Podomere No. Size Range Exopod. ,/Endopod. (mm)

Within the brood chamber of the female or inside the tunicate barrel; 1 O.'O 0.50-0.65 J u v e n il e head highly raised; pleon and urosome small; gonads not yet devel­ 2 1/1 0.9- 1.6 oped. 3 2/2 2.2- 3.2

-M Gonads slowly developing; size increasing rapidly; segmentation 4 3/3 3.5- 4.5 A not started yet in the flagellum of antenna 1 L 5 5/4 5.5- 6.5 E immature F Gonads slowly developing; size increasing rapidly; oostegites not yet 4 3 3 4.0- 5.0 E developed 5 5/4 5.5- 7.5 M 6 6/5 7.0- 9.0 A 7 8/7 9.0-12.0 L 8 9/8 11.0-13.0 E 9 10-12/ 9-11 13.0-16.5 10 13-15/11-12 15.5-20.0 11 16 13 20.0-23.5 12 17/14 22.0-25.0

-M Gonads developing fast; incomplete segmenfafion in the flagelium 6 7-S/6-7 7.0- 8.5 of antenna 1 \d o le 5 C e n t F Gonads developing fast; oostegites started to develop but incomplete 13 18/15 22.5-26.0 14 19/16 23.5-29.5

iM Gonads and flagellum of antenna 1 well developed; undulated dorsal 7 9/8 8.0- 9.0 A pleon margin 8 10/9 8.6-12.0 L E Mature F Gonads and oostegites completely developed; brood chamber well 15-? 20-26/17-21 25-42 formed as eggs ejected M/2f *♦/;*« -

2 l/l9 to/7 I9ll« 14 ia/l5 13

o ; t/(4 , 12 Q. , k„L // « la/it - ^/4/« 10 1 8/// y j 2 «/>/

!«>/»

t/r oa E 7 /« •§ £ sjt A .® »/4 -sili 5 3/S

a/a ^113 j- J— I—L J___L _L 3 a ? 9 II 13 m 17 19 21 2 3 23 27 2 9 31 33 33 37 Tot 0 I body length (mni

Fig. 10. Length frequencies of females (including the sexually indistinguishable juveniles) of P. sedeniaria. Specimens taken at Dana stations 4017-19. Each dot represents one specimen. Numbers besides histograms represent the stages. gate into groups of similar size but also show a resemblance in morpholog\’ and sexual development. This close relationship is therefore not considered to be a mere coincidence but rather to illustrate a significant increase of podomeres through the process of moulting. This has already been suggested by K ane (1963 a). The present case offers additional evidence that this kind of relationship may be found in other amphipods. It is interesting to note that from stage 4 to 5, in both male and female of P. sedeniaria, the podomere number increases from three to four in the endopodite, but from three to five in the e.xopodite. It is therefore not feas­ ible to suggest from the present study that there is a moult between every two successive stages of the present classification. Observation on living material is necessary before drawing a conclusion. If the presumption that the podomere number in the pleopod rami is closely related to the moulting is correct, then certain phenomena common to all species of this family become clear.

1. The large species pass through more moults during the life span while the small species have fewer, e.g., 15 or more stages for the female of P. sedeniaria, and 9 for the female of P. pacifica. 2. The size difference between the female and male of the same species is also expressed in the differ­ ence in the number of moultings. P. sedeniaria has the largest difference in size between the mature male and female and also has the largest differences in stages, while those species with small differences in size between the mature male and female have only one or two stages less in the male, e.g., P. coUetli and P. slebbingi. 6

3/3 t . __l_____ X -L 4 5 6 7 8 9 10 Total body length (mm)

Fig. 11. Length frequencies of males of P. sedentaria. For other explanations, see flg. 10.

3. The increase in size takes place mainly in the immature period. The larger the species, the more stages it passes through during this period, e.g., among the females, P. sedenlaria, 9; P. allanlica, 5; and P. curvi- pes, 4. 4. The period of adolescence consists of only one or two stages. During this period the reproductive organs develop rapidly. The secondary sexual characters also start to appear. However their development is completed at the beginning of the mature period.

The growth of the flagellum of the antenna is different from that described by S ex to n (1924), S e g e r s t r a l e (1950) and K ane (1963 a). S ex to n has noted that in Gammarus chevreuxi a new joint is added to the primary flagellum of antenna 1 from its proximal joint. According to S e g e r s t r a l e , in Pontoporeia affinis, a gammarid amphipod species, the first new segments of the flagellum of the antenna are derived from the division of the proximal segment during the whole course of development. The distal segments however begin to divide into two in a later stage. These newly formed segments then remain undivided until the last moult, during which every segment is divided into two, so that the flagellum is suddenly elongated. K a ne (1963 a) made observations on the moulting of Paralhemislo gaudichaudii. Although she did not give the detail of the devel­ opment of the flagellum in the antenna 1 of the male, from her drawing (fig. 7), it seems that in this species, the flagellar joints have gradually increased in number and in length during the course of development. In the Phronimidae, the manner of increase of flagellar joints of both pairs of antennae is similar to that of antenna 1 in the male of P. sedenlaria described above and differs from those first mentioned. The seg­ mentation of the inner tissue is almost complete in the adolescent period, but the complete formation of joints occurs suddenly in the last moult previous to the mature period. The different patterns of the development of antennal flagellum seem to be related to the general modes of the development of secondary sexual charac­ ters in different species. In Gammarus chevreuxi, the male sexual characters develop gradually and continue after sexual maturity is reached, and the growth of the antennal flagellum is also gradual. In Pontoporeia affinis and in the Phronimidae, the mature stage appears suddenly, the elongation and segmentation appear in the last moult. This parallel development of the antennal flagellum and other sexual characters presum­ ably is under the same control mechanism, most probably hormonal. Table 4. The stages of development and growth of species of Phronimidac (excluding P. sedentaria) based on the development of the reproductive organs and the podomere number in the pleopod rami. a. number of stages; b. size range within the period; c. range of podomere number within the period in exopodite/ endopodite of the pleopod; F. females; M. males. The largest sizes of the mature specimens are those seen in the materials of the present study.

Juvenile Im m ature Adolescent Mature a b a b a b b

3-8 9-10 11-15 5 4.0-9.5 2 9.0-12.0 11-25 0-2 3^ 8-9 10-13 Phronima atlanlica — 3 0.5-2.5 0^ 3-6 7-8 9-10 M 3.5-7.S 2 7.0-8.5 8-11 3-5 6^ 8-9

0-? ?-9 10-11 13-17 P. solHaria F ? 0.5-? 7-10.5 2 10-12 13-24 (T? 9-10 11-15

3-5 7-10 3.0-5.5 1 5.0-7.0 6.5-14.5 0-2 3^ 6 ^ P. pacifica 0.5-2.5 3-5 6-7 7-10 2.8-5.5 2 5.0-6.5 6.5-S.5 3-4 5-6 6-9

2-4 5-6 7-9 F 3.0-5.0 2 4.5-6.5 6.5-11 0-? 2-3 4-5 6-8 P. colletti _ 7 0.5-? 0^ 2-4 5-6 3.0-4.5 2 5.0-6.5 6.3-S.5 2-3 4-5 6-7

3-7 10-14 3.0-8.0 1 7.5-9.0 8.5-17 0-? 3-6 8-12 P. curvipes — ? 0.5-? 0^ 3-5 M 3.0-5.5 1 5.S-6.5 6.0-9.2 3^ 6-7

3-4 5-6 7-9 2.7-5.0 2 4.5-6.S 5.5-9.5 0-? ^3 6-8 P. stebbingi - ? 0.5-? 0^ 3-4 6-7 M 2.5-4.S 1 4.5-6.0 5.5-7.6 2^ 5^

3-4 5-6 3.0-5.5 2 5.0-9.0 9-14.5 2-3 4-5 Phronimella elongala — ? ? 3-4 5-6 M 3.0-5.5 2 5.5-8.0 7.5-12 2-3 4-5

Propagation

The manner of development and growth described above will help to understand the spawning habits of the phronimids. Laboratory observations on the breeding habits of the amphipods are known for the gammarids only. S e x t o n and M . \ t t h e w s (1913) have reared Gommarus chevreuxi, a fresh and brackish water species, in the laboratory. They reported the following findings: The time of sexual maturation of the female is at least thirty-six days after hatching; for the male, in one instance, fifty-two days. Breeding continues all year round in the laboratory and very probably also in the waters near Plymouth. The males takes the female when their reproductive gonads are becoming mature and carries her for some time before mating takes place. After ejecting all the juveniles of the first brood from her pouch, the female proceeds to moult. In the presence of the male eggs will be deposited in the pouch after the completion of moulting. If the female is isolated from the male, then the eggs will not be deposited but will increase to a very large size. In ideal conditions, the mating may occur once a fortnight. The temperature seems to play an important role in breeding: low temperature not only hinders the development of the gonads in the young individuals but also delays the subsequent oviposition in the mature female (B l e g v a d , 1922). He observed another marine gammarid in Danish waters, Gammants locusta, closely related to G. chevreuxi. The breeding season lasts from the end of January to some time in October. The time for sexual maturation is highly variable. It may be longer than two months for the females born at the beginning of the breeding season and approximately one month for those born in the middle of August. Similar to G. chevreuxi, the mating will take place after the completion of the hatching of the eggs and the subsequent moulting of the female. A single female may give birth to up to seven broods in her life. Pontoporeia affinis, a brackish water gammarid (an arctic relic in Finnish water), behaves differently from the two Gammarus species just mentioned. According to S e g e r s t r a l e (1950), the females die after producing one brood. More data on propagation in freshwater, brackish and marine gammerids are scattered in the literature and most of them are reviewed by B legvad (1922). For the pelagic hyperiids information on this aspect is unexpectedly scanty. There is none in the literature for the vast numbers of tropical and temperate species. For the northern forms an excellent example was given by Di n b a r (1957), based on material collected on the Calanus Expeditions of 1947 to 1955. As stated by Di n b a r , in Themisto libelliila breeding extends from September through the winter until some time in May or June in Hudson Bay, Hudson Strait, and the waters of southeast Baffin Island. Since there are no spent specimens of either sex taken, except in March at the height of the breeding season, he presumed that the Themisto libelliila individual breeds only once and dies.

Time of Sexual Maturation. From the material used in the present study no reliable information can be given on the time needed for the complete development of gonads in phronimids, because of two main factors. First, except for the Bar­ bados and CCOFI collections, which have been sampling the same area repeatedly for a considerable period, none of the present material is suitable for such a study. The material of the Barbados waters and the CCOFI cruises moreover, were collected from the surface layer which contains mainly the young stages. Secondly, as will be explained later, the spawning of the phronimids very probably extends through most if not all of the year, and each individual again is likely to breed more than once. The continuous recruitment of the new generation into the population makes the analysis difficult, unless the method of collection is specially designed. Although the time taken to reach sexual maturation is not available from the present material, a com­ parative figure can be deduced from the manner of growth summarized in tables 3 and 4. If the presumption that the stages described are related to the moulting is correct, then it is clear taht generally the male would reach maturity in less moults than the female. If we suppose that the time elapsed between every two suc­ cessive moults is the same in both sexes, which is probably true, at least in the immature period (excluding P. sedentaria) and may be up to the early adolescent period (e.g., P. pacifica, P. colletti and P. stebbingi), then the time needed for the complete development of gonads in the males would be shorter than that in the females of the same species. This supposition of course should be taken with reservation, since there is no evidence to assure that the rate of moulting is similar in both sexes, although neither is there for the opposite.

Breeding Seasons. Mature female and male phronimids are, with few exceptions, found together in every positive Dana station, i.e., stations where phronimids are found. Before making any conclusions on the spawning, it should be realized that the Dana Expeditions, although covering the tropical and temperate parts of the three oceans, were not designed to cover the investigated route repeatedly. It is thus apparent that the collections demon­ strate only an “instantaneous aspect” of the whole picture. To compensate for this disadvantage, which is true of most oceanographical expeditions, data from other sources containing records in adjacent waters Date Locality Remarks Reference

7. 3.1874 50°01' S. 123°04 E. ? with eggs S t e b b i n g , 1888 9.-10. 3.1874 48°18' S. 130°04 E. ? with juv. 12. 5.1875 35“11' N. 139°28 E. 5 with eggs 19. 1.1910 40°53' N. 13=43 E. 0 with juv. Stephenses', 1924 28. 6.1910 38° 17' N. 4°11 E. $ with eggs 1. 7.1910 42“31' N. 7°41' E. $ with eggs & with juv. 10. 7.1910 42“43' N. 9°50'E. $ with juv. 29. 8.1910 40°34' X. 3°03 E. 24. 2.1910 35°53'N. 7=26' W. $ with eggs 28. 2.1910 36°13' N. 9°44 W. 3.10.1910 47°0r N 5°48 W. 17. 9.1910 47^14'N. 6°02‘W. ? with juv. 14. 6.1905 51^32'N. 12=03 W. & with eggs

20. 6.1905 48=09' N. 8=30 ^Y. 2 with eggs 29. 8.1905 61°20'N. 11=00 W. c with juv. 29. 8.1905 60“00' N. 10=35 W. 11. 5.1906 48“42' N. 12=20 ^Y. 5 with eggs 5. 6.1906 50°25'N. 12=44 W. 6. 9.1906 49“23'N. 12=13 W. 31. 8.1906 49°31' N. 11=51' W. 3. 9.1906 48°19' N. 13=53' W. 5 with juv. 31.10.1901 30°21' S. 14=02' \V. 9 large oostegite M o g k , 1927 b 2. 6.1922 33°12'N. 10=20' \V. ? with juv. PiRLOT, 1929 23. 6.1922 43“32' N. 24=40 W. 26. 6.1922 47°10' N. 18=02' W. 8.10.1899 0°17.6' S. 129=14.5' E. PiBLO T, 1930 10. 8.1899 0°19' S. 129=15 E. 26. 3.1912 of Campbell Island B a r n a r d , 1930 16.10.1925 17=24' N. 18=15'W. B a r n , \ r d , 1932 28.10.1925 13=25' N. 18=22' \V. 13.11.1925 3=50' S. 12=54'w. 5. 6.1926 39=50' S. 36=23'\v. 18. 6.1926 32=45' S. 8=47'\v. 14.10.1926 33=50' S. 16=04'E. & with eggs 2. 6.1927 46=56' S. 46=03' \V. 17. 6.1927 36=09' S. 5=33'\V. 25. 7.1927 18=37' S. 10=46'E. 16. 8.1927 2=43' S. 0=56' \V. & with eggs 24. 4.1927 48=50' S. 64=24' W. $ with juv. 30. 3.1905 43=17'N. 7=22' E. C h e v h e c x , 1935 13. 8.1905 31=44'N. 42=38' \V. 30. 8.1905 39=36'N. 26=05' W. 29. 8.1905 38=04'N. 26=07' w. 9. 4.1906 43=17'N. 7=52' E. 21. 4.1909 43=38'N. 7=32' E. 22. 8.1910 44=19'N. 11=19' \V. 15. 8.1911 33=40' N. 19=00' \V. 27. 8.1911 38=00'N. 25=28' \V. 24. 8.1912 39=26' X. 35=14' \V. 1. 9.1912 45“02'N. 13=05' \V. 15. 2.1933 12=08'X. 63=04' E. B a r n a r d , 1937 b 7. 3.1930 45=53' S. 84=33' E. H u r l e y , 1960 b 10. 3.1930 43=19' S. 93=56' E. Nov. 1905 Irish Atlantic slope T a t t e r s ALL, 1906 are referred to in tables 5 and 6. The complete picture of the breeding in different parts of the oceans can nevertheless not be given until materials are available of more recent collections, which not only pass repeatedly over the investigated route but also have many courses in the same ocean, e.g., the \orpac and the Inter- T a b le 6. Catches of breeding females of phronimids (excluding P. sedentaria) from the literature.

Date I.ocality Remarks R efe ren ce

Phronima allanlica U. 7.1910 38“19' N. 9=59'E. § with eggs St e p h e n s e v , 1924 25. 7.1910 32°38' N. 19=02' E. - - 2,i. 7.1910 31=35'N. 19=02' E. - 25. 8.1910 39°32'N. 10=49' E. - & with juv. - 30. 8.1910 41=10' \. 2=23' E. $ with eggs - 25. 6.1911 33=10' xN. 25=35' E. - & with juv. - 26. 6.1911 34=20' N. 20=10' E. ? with eggs 9.11.1911 35“10' X. 18=10' E. -- 25. 2.191.3 37°23' iV 9=25'E. - - 28. 8.1910 39=32' N. 5=15' E. -- 22. 7.1911 34=41' N. 16=04' W. - - 24. 2.1910 35=53'N. 7=26' W. -- 5. 6.1922 31=56' S'. 14=53' W. 5 with juv. M o g k , 1927 b 21. 4.1909 43°38' N. 7°32' W. - Ch e v r e u x , 1935 7. 8.1888 1=04' S. 127=53' E. - PiRLOT, 1930

Phronima pacifica 28. 2,1910 36=13'N. 9=44' W. $ oostegite large St e p h e .v s e n , 1924 10. 9.1903 8=43'N. 11=55'W. - M o g k , 1927 b

Phronima colletii 1. 3.1910 36=13'N. 9=44' \V. $ with eggs & with juv. St e p h e n s e n , 1924 17. 6.1910 37=03' N. 9=15' \V. $ with juv. - 18. 6.1910 35=53' N. 7=26' W. 2 with eggs - 22. 7.1911 34=41'N. 16=14' \V. - & with juv. - 23. 7.1911 31=23'N. 18=08' W. _ - 26.10.1911 36=48' N. 14=22' \V. $ with juv. _ 26.10.1911 34=23'N. 15=31' W. $ with eggs - 30.10.1911 32=10' N. 17=20' W. --

Phronima curvipes

23. 6.1910 35=57' N. 5=35' W. $ with eggs St e p h e n s e n , 1924 30. 6.1910 41=00'X. 6=43'E. _ _ 14. 7.1910 38=18' N. 9=39'E. _ - 19. 7.1910 37=37' N. 11=25'E. _ _ 27. 8.1910 38=52' N. 7=43' \V. _ _ 28. 8.1910 39=32' X. 5=15'E. __ 2. 9.1910 36=54' N. 2=57' E. _ 18. 6.1926 32=45' S. 8=47' W. $ with juv. B a r n a r d , 1932

Phronima slebbingi 11.10.1901 11=19' S. 18=34' \V. ? with eggs Mogk, 2927 b 8. 9.1903 9=21' S. 9=48' W. --

national Indian Ocean expeditions. Of all seas, the Mediterranean has the most detailed information avail­ able from Ihe literature in this regard. In the present investigation, an indication of the year-round breeding that generally takes place among the members of this family as explained below, is offered by the collections from two particular areas: the water adjacent to Barbados and the eastern North Pacific. In the first area a two-year collcction taken weekly is available (L e w is , et al, 1962), and the second is part of the CCOFI collection containing samples from March, July and November cruises (Anonymous, 1951). Besides those listed in tables 5 and 6, observations on spawning have been made bv several other authors. ScHMmTLHi.N (1879), working from three years of observation, found the breeding season of P. sedentaria in the Mediterranean to extend from late January to April. C h u n (1896) suggested that for this species, spawn­ ing takes place in the spring in the Mediterranean and in January in the adjacent waters of the Canary Islands. Lo Bia.nxo (1909) noted that in the Bay of Naples, P. sedentaria breeds mainly from November to April, but also in August, although much more rarelj'. Stephf.nsen (1924), based on the records known from the literature, and the result of the Danish Oceanographical Expeditions, specified the time of pro­ pagation for this species in the following manner: South-west Ireland, summer and autumn; Bay of Cadiz and Mediterranean, winter and early spring; the Canary Islands, January, and perhaps at other seasons. Mogk (1927 b) found that the 5th to 7th instars of both the females and males are dominant in P. sedentaria of the Gauss collection and therefore supposed that the spawning of this species might not fall in the period of August to November in the area (Atlantic and Indian Oceans) surveyed by the expedition. Since he recorded a female with fully developed oostegites of a size of 30.7 mm, and since from the observation of the present investigation females with large oostegites always have well developed gonads, his supposition deserves serious consideration. In the South Atlantic Ocean (south of 30° S), B a r n a r d (1932) found females of P. sedentaria with ova in October and with 1st instar juveniles in November, an indication that breeding took place in the spring or summer. , From the known records from the literature as well as from the materials of the present study, it appears that propagating females of P. sedentaria are found through the months of November to September in the western part of the Mediterranean. In the Atlantic off the African coast, they are recorded in the months of January to March, June, August and September. South to 45° S in the oceans, the egg- or young-carrying females have been reported in January, March, April and June. It is apparent that almost every expedition which has collected this species has taken breeding females. The Barbados and CCOFI samples provide contrasting evidence. Only a few immature female specimens are present in the two-year period of the first collection, probably due to the fact that the station is too close to the shore. In the CCOFI collection, the immature form of female P. sedentaria is present frequently throughout samples of all the cruises. The lack of more mature female specimens possibly is realted to the depth at which the samples were taken; the CCOFI plankton samples available for the present investigation were hauled at a depth of about 70 meters. For P. atlantica, many females with ova or embryos were recorded by Stephensen (1924) from the Mediterranean. He speculated that breeding might take place in this area the year round, perhaps to a lesser degree in the winter than in other seasons. D u d lic h (1926) suggested two breeding seasons for this species as well as for P. sedentaria living in the Mediterranean; November-December, and March-April. According to him, there are two populations in the Mediterranean. The autumn population ascend to the surface in October and breeds in November and December; while the spring population ascends in February and breeds in March and April. This seems improbable since from the literature and the present investigation, breeding females of P. sedentaria are found almost throughout the year, while those of P. atlantica have been recorded in the months of May to August. In the Barbados waters, although the immature form of P. atlantica is present frequently throughout the collection, the adolescent form is rare and only two mature specimens are recorded in January. In contrast to P. sedentaria, females of atlantica which carry ova or embryos or possess well developed gonads are, on the other hand, present in the CCOFI collections from all of the cruises (Californian coast). Fewer data regarding breeding are available for the other Phronima species. No record of breeding females of P. solitaria has ever been reported in the past. For the remaining four species, pacifica, colletti, curvipes and stebbingi, female specimens with ova or embryos are more frequently present in the collections than the other three species. Stephkxsex (1924) found egg- or young-carrying females from seven out of twenty-two positive stations in the Mediterranean for P. curvipes, and from eight out of nineteen positive stations in the Atlantic for P. colletti. From the present investigation, it is found that females at the mature period, i.e., those females with well developed oostegites and gonads as well as those with ova or embryos in the brood pouch, are represented in almost every positive haul for these four species. A most remarkable fact revealed by the Dana material is that the mature individuals of these species usually outnumber the specimens of other stages. In Barbados waters, females of P. pacifica were taken in January, February, April, June to August and October to December. The mature females were present in all these months except February and December. The females of Phronimella elongata, which carry ova, but never embryos, in the brood pouch are found only in a few cases in the present study. Stephensen (1924) recorded 3559 female specimens from the Medi­ terranean but failed to find a single breeding individual. Excepting the statement made by Lo B ianco (1909), who remarked that in the Bay of Naples the species has ova in the brood pouch in August to November and embryos in November to January, no finding has ever been recorded in the literature. The failure to find mature females of this species is very probably due to the structure of the brood pouch. From the preserved material of the present study, it is noted that the oostegites of this species do not develop as well as those of the Phronima species. \\'hen fully developed, the oostegites hardly attach to the opposing ones. The brood pouch is therefore in a sense not perfectly formed. The imperfection of the brood pouch might be the principal factor which makes the eggs or embryos contained in the pouch likely to be lost either during the course of hauling or when the fixative is added to the plankton sample. In the present study, females with imperfect brood pouches but without either ova or embryos, as well as with small oostegites and well developed gonads, are found abundantly among the samples. This suggests that the manner of propagation is similar to that of Phronima species. From the foregoing description it seems obvious that, among the members of this family, breeding takes place during most, if not all, of the year. This is supported by the evidence that P. sedentaria spawns almost the year round in the Mediterranean and that immature females of P. atlantica are present in the Barbados collection throughout the two-year period. The complete absence of mature females in the last instance, in my opinion, does not nuUify the present conclusion. The mature females might live in an environment outside the sampling area, either horizontally or vertically. Nevertheless the frequent presence of the immature forms means that the area surveyed is continuously supplied with new broods which implies that breeding occurs throughout the year. The breeding might be limited to a shorter period at the extremity of their di­ stribution in the higher latitudes, presumably due to the low temperature. However the following facts should be taken into consideration: G o r d o n (1881) reported two females of P. sedentaria which were washed up on the shores of Shetland (north to 60° N) in January with embryos in their brood pouches; B a r n a r d (1932 b) recorded a young-carrying female of the same species from the South Atlantic (46°56' S, 46°03' \V) in June.

Number of Broods per Individual. Laboratory study is needed to provide reliable information on this point. The following discussion is based mainly on morphological observation of the spent females. Contrary to D u n b a r ’s (1957) arctic hyperiid, spent females usually amount to an important portion of the total mature specimens. The large number of spent specimens may partly be due to the reasons de­ scribed for Phronimella elongata (see above), but it is probable that phronimid females do in fact spawn more than once per lifetime, as is shown by the following observations: The ovaries of the females which carry ova or embryos in the pouches are rudimentary, similar to those found in the immature specimens, and they lie on the latero-dorsal surface of the midgut; the oviducts are hardly visible and cannot be traced to the opening at the base of the last pair of oostegites. More than half of the spent specimens possess rudimentary ovaries and delicate oviducts exactly Hke those found in the egg- or young-carrying females. This may suggest that they are either propagating females that have lost their eggs or embryos some time between the hauling and the handling of the samples, or that they have recently discharged the young, and their gonads arc at a resting stage, similar in appearance to those of the imma­ ture individuals. The rest of the spent females have their gonads in the recovery stage, and are characterised by gonads like those found in the female of the adolescent and early mature periods. By the time the gonads are fully developed it is hard to judge whether a given female has or has not spawned before. This is due to the fact that the oostegites in the female phronimids do not disappear or become atrophied (S ie b o ld BOLD and S t a n u s, 1854) or decrease in size ( B r u z e l u s, 1859) as in other amphipods. An interesting account on spawning is given by D udlicii (1926). According to this author’s laboratory ob­ servation, a pregnant female of P. atlantica discharges her eggs into her pouch not in one discharge, but in three discharges. The interval between two successive discharges is three days. If this is true, an interval of six says between the first and the last batches of eggs discharged might result in a great difference between development stages of the offspring. This seems to be so in the case observed by Dudlich as he described later that the juveniles also leave the brood pouch in three groups, each with an interval of three days. In the present study, the juveniles of both P. sedentarin and P. atlantica in two different stages were found together several times in the same brood pouch or in the same barrel of the tunicate. These are usually prehatching embryos and 1st stage juveniles in the brood pouches and the 2nd and 3rd stage juveniles in the barrels. B a r n a r d (1932 b) also found two instars of juveniles in the same tunicate barrel.

Food Habits

The gut contents of many specimens of various sizes of all species from different depths have been exam­ ined, and are found to be uniform in character. They mainly consist of algal cells, mainly diatom shells, but crustacean remnants are also usually present. These remnants include the antennae, mouth parts, other appendages and body exoskeletons, mostly of calanoid copepods, but some are not recognizable. The first appearance of food contents in the gut is found in the 3rd stage (table 3) of P.sedeniaria and in the same stage of P. atlantica. At this stage, the juveniles are still carried in the tunicate barrels, and without exception, the contents found in the guts are phytoplankton only. The structure of the mouth parts (fig. 12) of phronimids does not suggest that they are filter feeders.

Fig. 12. Mouth-parts of Phronima solitaria G u e r i n . - a. Lower lip; b. Mandible: c. 1st maxilla; d. 2nd maxilla and e. Maxilliped. As early as 1889, B o v alliu s had already noted the similarity of the anatomy of the mouth parts within the genus Phronima; there is furthermore no significant difference between those of Phronima and Phronimella, except that the denticles on maxilla 1 are comparatively stronger in the latter. Setae on maxillae 1 and 2 and maxillipeds are generally short and smooth, without bristles. The mandibles have a cutting plate of triangular shape on the medial side. The cutting plate, in addition to some short setae, is armed with several rows of denticlcs along its medial edge. These particular structures presumably are useful for tearing and grinding. This may partly explain why the crustacean remnants found in the gut contents are usually in fragments. There are no other structures in the phronimids whcih serve as efficient filtering mechanisms for feeding. In the females, only the first pair of antennae are present, but these are short. In the males, only the mature individuals possess well developed antennae. It is therefore unlikely that these structures could help in feeding. The peraoopods possess only scattered short and unbranched setae, or none at all. The setae on the rami of the pleopods are long and bristled. When not actively moving, the pleopods keep gently beating to supply a current of freshly, oxygenated water to the gill pouches under the peraeon. By wafting the water forwards, the food particles might at the same time be forced towards the anterior end of the animal. It has never been observed in the aquarium that the animal uses its peraeopods to scrape the pleopod setae. It seems therefore reasonable to suggest that the phronimids as a whole are omnivorous. They might be partly predatory and partly vegetarian. The dominance of phjioplankton in the gut contents is ambivalent evidence, since these plant cells might be secondarily taken through the prey as well as directly introduced from the medium.

Relationship to the Other Animals

The phronimids are remarkable for their relationship with the jellylike barrel of the tunicates. M in k ie - wicz (1910) has fully described the behaviour of P. sedentaria. The females of this species are seen to mani­ pulate the barrel very skillfully by using their peraeopods and the position of the body to drive the barrel in a desired direction. Their presence within the barrel is probably somehow related to breeding. D ld lic h (1926) has found that in the Mediterranean the Phronima (mainly sedentaria and atlantica) and the tunicates, Pyrosomn, have similar times of appearance and of bethymetric distribution. In the Dana material of the present investigation, there are many barrels of tunicates, mainly of Doliolum, and lesser numbers of Snlpa and Pyrosoma, also a few siphonophores. However, since they are in most cases placed in separate vials from the phronimids, it is useless to make any further statement about the rela­ tion between the tunicates or siphonophores and the phronimids. For the few barrels whcih still contain phronimids, it is found that in all but one case, the females carry ova or embryos or are spent females together with offspring. Xo females of P. coUetti, P. pacifica and P. stebbingi are found within the tunicate barrels either in the present material or in the literature. The males are not known to be in the barrels except for the remark quoted from A. W . B. Pow ell (1947, p. 36), “Remarkable for the habit of the male (sic) (of P. sedentarin) of excavating the body of a transparent jelly-like pelagic or floating seasquirt, known as a salp, and taking up her abode within.” Phronima species have been seen floating or drifting in the surface water (Adams, 1850, p. i) and have been reported to have been washed up on the shores (G o rd o n , 1881; C hilto.n, 1911). Although phronimids are seldom found in large numbers in the seas, they are still frequently recorded from the gut contents of fishes. P. sedentaria has been taken in the stomach contents of the albacore, Germo alahingn (Chevreux, 1900; Jouni.N and R o u le , 1918; L e g e n d r e , 1940 and M c H lg h , 1952) and of tuna, Thynniis pelamys ( B a r ­ n a rd , 1932 b). C h e v re u x (1900), L e g e n d r e (1940) and M cH ugh (1952) also reported P. atlantica in the albacore. IV. DISTRIBUTION Vertical Distribution

The phronimid species have been classified as epipelagic (S t e p h e n s e n , 1924) or bathypelagic (E kman, 1953; H u r l e y , 1956) planktons. In the present investigation, as was mentioned, the majority of the material examined was collected by the Dana Expeditions 1920-1922 in the N. Atlantic and the Gulf of Panama and 1928-1930 round the world. The positive stations (stations at which phronimids were taken) of these expeditions together with the catch of specimens are listed in the Appendix Table 3 A-C. The depths of hauls of the Dana Expeditions generally fall into two major categories: in the night hauls, the lowest nets are towed at 1000 M.W., which is also the upper level for the day hauls. If the gear is towed with 0-1000 M.W., the real depth of the haul may be roughly estimated as one-third of the metres of wire out; however, if the gear is towed with 1000 M.W. or more, then the actual depth is about one-half of the wire length (B r u u n , 1943) It is therefore important to determine for the hauls made at 1000 M.W. to which series they belong. Table 7 gives the synoptic result of the catches of all species from various depths. It is shown from table 7 and Appendix table 3 A-C that the phronimids are most abundant in the depths of upper 1000 M.W., but still are represented in fair numbers in deeper layers and have been taken twice from the deepest hauls (7000 M.W.). That the phronimids are scarcely found in the surface hauls may be mainly due to the fact that while fishing intensity at depths of 30 M.W. and below was about the same (S 200 net and 2 hours of hauling in most cases), it was much lower at the surface (S 50 net and 5 minutes, or approximately 1/19, S 200 hour). This should be born in mind when discussing the vertical distribution. The fishing technique of the Dana Expeditions generally follows that of the Danish Oceanographical Expeditions (Thor) described by Schmidt (1912). The only improvement is that several nets are towed at different levels of depth simultaneously (S chm idt, 1929; J e s p e r s e n and T.In in g , 1934). The simultaneous use of several horizontally towed nets might be expected to produce a more complete picture of the animal distribution at different depths at a particular time, but it is in fact handicapped by the use of non-closing nets. There is no doubt that animals in the upper water layers may be accidentally caught when the net is being lowered away or pulled in to the ship. If the net is towed at shallower levels, this accidental catch might not alter the results appreciably but it will certainly amount to a large portion of the total catch in the deep hauls. The speed of putting out and hauling in the nets is about 20 to 30 minutes per 100 M.W. (B r u u n , 1943). If we take the lower figure for the speed and consider that the net is towed for two hours at the desired depth, the ratio of time taken in lowering or hauling to the time of towing horizontally would be 2 :3 for a 2000 M.W. haul and 2:1 for a 6000 M.W. tow. For this reason, more attention is paid to the catches of the upper 1000 M.W. which are believed to provide more reliable information than those of the deeper tows as regards vertical distribution. The phronimids were caught with several kinds of gear during the expeditions, namely, the stramin nets S 200, S 150 and S 50, the silk net P 100 and the ring trawl E 300. Supposing the relative amounts of water strained per hour of hauling of different nets is proportional to the diameter of the net used, a simple relationship is consequently derived that 1 S 200 hr. = 2 S 150 hr. = 16 S 50 hr. = E 300 hr. and this will be adopted by the present investigation. In discussing the vertical distribution, B ruun (1943) and T h o r e (1949) have estimated the number of specimens caught at a certain depth by subtracting the estimated catch above this depth from the total catch M. W. I II III IV V VI VII VIII abcabcbabcabcabcabcabc

0 ...... 1 2 0 0 4 2 1 0 0 2 0 1 0 0 1 0 0 0 0 1 3 2 50 ...... 25 14 1 32 10 2 10 13 14 3 13 7 3 8 12 4 6 3 2 17 4 3 100 ...... 31 16 1 29 8 7 9 16 10 0 12 5 2 12 15 S 6 3 2 23 7 1 200 ...... 3 9 0 2 0 0 0 0 0 0 0 0 0 0 0 2 0 0 0 0 0 0 300 ...... 38 22 2 27 13 6 13 7 10 3 9 7 0 10 24 2 5 9 0 20 7 0 400-500 ..78153040301203 5 0000000 600 ...... 31 28 2 16 13 3 10 1 8 4 2 10 2 9 18 1 4 2 1 15 1 4 700-900 ..350320040001 02100101 10 1000 ...... 10 115 6 10 9 6 7 1 4 2 1 6 0 0 14 1 1 3 2 10 4 0

1000 ...... 16 4 2 1 1 2 3 2 1 2 0 2 3 0 7 5 0 1 2 2 6 2 2 1500 ...... 8 6 1 6 3 2 1 0 0 1 0 0 0 0 3 0 1 1 1 5 1 0 2000 ...... 16 5 1 14 0 3 1 2 5 2 2 5 0 0 5 1 1 2 0 8 7 1 2500 ...... 8 3 0 4 2 1 1 1 0 0 1 1 0 1 3 0 0 0 0 1 1 1 3000 ...... 10 11 3 10 4 3 0 0 5 2 1 5 2 2 4 2 2 2 1 9 0 0 3500 ...... 7 4 2 4 1 3 3 2 0 1 1 1 1 0 3 1 0 1 1 3 3 1 4000 ...... ti 8 0 6 3 1 2 1 1 2 1 2 1 0 3 0 2 1 1 1 3 1 5000 ...... 3 9 0 3 1 4 0 1 2 1 2 0 0 0 2 0 1 0 0 1 2 0 6000 ...... 0 3 0 0 1 0 1 0 1 0 1 0 0 0 1 0 0 0 0 0 1 0 7000 ...... 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

I. Phronima seilentaria, II. P. attantica. III. P. soUlaria, IV. P. pacifica, V. P. colletti, VI. P. curuipes,, VII. P. stebbingi and VIII. Phro- nimella elongatii. a. both sexes, b. only female and c. only male present in the haul. - The numbers in the columns represent hauls positive for the various species.

of the haul. This is believed to give good results. In the present study, their metod is followed but with modification. The principle on which the estimation is made can be quetioned since the planktons are not expected to be distributed evenly within a certain depth of water, but rather in a patchy pattern. For instance, Paralhemisto gaiidichaiidi and Vibilia aiitarcticn are found to be distributed in patches (Hardy and Gu.nther, 1935). Phronimids are known to occur more or less in shoals. Pbromina sedentaria is found to occur in shoals of about 10 specimens while Phronima atlantica, P. colletti and Plironimella elonyata may aggregate in 20, or up to over 100 .specimens per haul (Stephi;.\sen, 1924: p. 234). In the Dana collection, P. colletti occurs usually in small numbers per haul, but at Dana Station 4000, almost nine hundred specimens were caught in a single haul (50 M.W.), Since there is no better way to demonstrate the vertical distribution of the material collected by open nets, the present method, even though uncertain, is still considered to be practical. For explanation of this method, an example is illustrated in Appendix table 2. To understand the vertical distribution of the phronimids in various waters, stations which produced large numbers of specimens have been chosen for study. These include Dana Stations 3689, 3690, 3712-15 in the South China Sea; 3893, 3902, 3903, and 3905 in the eastern Indian Ocean, stretching from north to Suma­ tra westward across the Bay of Bengal; 3962, 3964 and 3969 in the western Indian Ocean off the southeast coast of Africa and 3978, 3980, 3996, 4000, 4003, 4005, 4007, 4009, 4017 and 4019 in the Atlantic Ocean olT the west coast of Africa. These stations are chosen not only for the abundance of the phronimids caught but also because they give a representative sample of the areas investigated by the Dana. The result calculated according to the method illustrated in Appendix Table 2 is summarizetl in table 8. Specimens of different stages of the same sex are lumped in the calculation. This is done because of the irregular occurrence of specimens based on the developemnt stages and is believed to give a better interpretation for general purposes. This table contains only the data of hauls taken at and above 1000 M.W., and therefore includes all belonging to the night collections. From the values of the catch per 1 S 200 hour, several points in regard to the vertical distribution are suggested: Surface 50 M.W. 100 M.W. 300 M.W. tiOO M.W. 1000 M.W.

1) b b b a b c a b c

Phronima sedentaria A ...... 0 0 5.7 (I 0. / 18.7 8.8 27.5 18.9 19.4 38.3 2.1 2.8 3.8 0 (1 II B ...... 0 0 25.2 5.3 ,30.4 15.9 2.0 17.8 3.6 3.0 6.6 4.0 2.1 6.4 0 0 (1 (',...... 0 0 1.7 1.0 2.7 3.5 2.0 5.5 0.9 0.8 1.7 0.7 0.5 1.0 0 0 0 D...... 0 0 22.4 2.2 24.5 28.1 6.9 35.0 19.8 10.0 29.8 14.4 8.6 21.5 11.02

Phronima atlantica A...... 0 0 4.1 3.7 7.8 12.6 8.9 21.5 3.7 4.4 7.1 0.1 0.5 ^1.5 (1 (1 0 B ...... 0 0 11.1 5.8 16.8 6.0 3.7 9.6 3.0 1.3 4.2 2.0 0.4 2.2 0. 1 0.1 0. C ...... 0 0 10.2 11.5 21.7 1.7 1.3 3.0 0.2 0.03 0.1 - 0.5 0.4 0 D ...... 0 19.2 19.2 7.8 5.5 13.3 4.6 2.7 7.2 2.5 2.2 4.4 1.6 0.1 1.9 0.01

Phronima solitaria C...... 0 2.3 2,3 1,5 1.5 0.3 0 0.3 0.7 0 11.7 0 0 0 D...... 0 0.3 0.3 0.5 0.5 0.7 0 0.7 0.9 0 0.9 0 0 (1

Phronima pacifica A...... 0 0 0 7.4 5.2 12.6 9.6 1.6 11.1 0.6 1.0 1.5 - 0.1 + 0 (1 1) a ...... 0 0 0 1.4 0 1.4 1.2 0.1 1.3 0 0 0 0.1 0 0.1 0 0 (1 C...... 0 0 0 1.8 0 1.8 • 0.1 0.2 0.3 0 0 0 0 0 0 0 0 0 D ...... 0 19.2 19.2 2.8 0.2 2.9 2.4 0.2 2.5 0.6 0.2 0.5 0.4 0.1 0.1 0.02 -

Phronima colletii B...... 0 0 0 2.2 0.8 3.0 0.5 0.5 1.0 0.3 0 0.2 0.2 0 0.2 0 0 0 C ...... 0 II 0 1.2 0.2 1.3 0.4 0.1 0.5 0.1 0 0.1 0.1 0 0.1 0 0 0 D ...... 19.2 0 19.2 44.8 0.8 45.5 4.8 0.8 5.5 0.4 0.2 0.5 0.3 0.1 0.3 - n --

Phronima curvipes A...... 0 0 0 0.5 0.3 0.8 3.4 2.5 5.9 4.6 0.5 5.0 1.8 0.2 1.7 I) 0 0 B ...... 0 0 0 0.7 0.2 0.9 1.2 0.6 1.8 0.6 0.8 1.4 0.8 0.1 0.9 II 0 0 C ...... 0 0 0 0.3 0 0.3 2.0 0 2.0 0.5 0 0.5 0.3 0 0.3 0.1 0 0.1 D...... , . 0 0 0 1.5 0.4 1.9 5.4 2.6 7.9 1.1 0 1.1 O.fi 0 0.6 0 n 0

Phronima stebbingi C...... 0 0.5 1.7 2.2 1.0 0.3 1.3 0.2 0 0.1 0 0 0 D...... 0 1.7 0.7 2.4 1.7 0.9 2,7 3.7 0.3 4.0 0.1 0.1 0.1

Phronimella elongala .\...... , 0 0 0 3.4 3,2 6.6 37.0 10.7 47.7 5.5 4.0 8.9 - - - 0 0 0 B ...... 0 0 0 3.7 1.9 5.7 2.8 1.2 4.0 0.4 0 0.4 0.2 0.3 0.4 0.4 ll.l 0.4 C ...... 0 0 0 5,3 4.7 10.0 22.1 5.0 27.1 0.4 0.6 0.9 -- D...... 0 19.2 19.2 5,6 3.5 9.1 9.3 2.9 12.1 1.9 0.2 1.9 0.6 0.1 0.4

A, South China Sea, B, Eastern Indian Ocean, C, Western Indian Ocean olT southeast Africa, and D, .\tlanlic Ocean alon;; the .\frica. coast, a, female b, male, and c, both sexes, - presence of catch in the sample, but after calculation, no catch is supposed to be caught at that depth,

1. Phfonimids are epipelagic planktons. The rare occurrence in the surface hauls at night iniglit be due to the low fishing intensity (0.01 to 0.05 S 200 hour in each of the examined areas). The 1000 M.W. tows usually yielded none or poor collections. 2. Although slight variations exist, the males and the females generally show a similar pattern in the vertical distribution, particularly noticeable in those species which yield more specimens, e.g., Phronima sedentaria, P. atlantica and Phronimella elongnta. 3. Phronima sedentaria has its highest concentration at the 100 M.W. in the South China Sea, the eastern Indian Ocean and the Atlantic Ocean, but at 50 M.W. in the eastern Indian Ocean (the significance of this is doubtful). Except for the eastern Indian Ocean, hauls at 300 M.W. still produce a very high catch, and a moderate number of specimens are present at 600 M.W. 4. Phronima atlantica is most abundant at 100 M.W. in the south China Sea but ascends to the upper layers in the other regions. 5. The patterns of vertical distribution of Phronima solitaria in the Atlantic Ocean and the western Indian Ocean are almost completely contrary to each other. This is believed to be due to the patchiness of the organ­ isms. A chance haul yielding a good catch in a less abundant species such as this will give misleading in­ formation. ti. Phronima pacifica and P. coUetti appear to be found mainly in the upper 100 M.W. It is shown in table 8 that no more than one specimen per 1 S 200 hour below 100 M.W. of either species was taken. 7. The highest concentration of Phronima ciirvipes is at 100 to 300 .M.W. Otherwise, its occurrence is similar to P. sedentaria. 8. Phronima stebbingi is found mainly in the Atlantic Ocean; also in the western Indian Ocean, but rarely. It is more concentrated in the layer of 50 to 100 M.W. in the former but 100 to 300 M.W. in the latter. 9. Phronimella elongata in all cases is most abundant in the upper 100 M.^^^, but a very samll number of the catch is still found in deeper hauls, including those at 1000 .M.W. All the above patterns, of course, are based on the results of night hauls. The statement for Phronimella elongata is, however, in agreement with the observations in the Adratic Sea of the Mediterranean made by S t e u r (1912), who also found that in the night this species aggregates near the surface but may also be found in small numbers to a depth of near 800 metres. As already mentioned, the day hauls of the Dana Expeditions were usually made at and below 1000 •M.W., and the night hauls at and above 1000 M.W. The depth of day 1000 M.W. haul was approximately 500 metres but the night tow was about 3000 metres. The difference in depths of day and night hauls makes the analysis of the vertical distribution and migration of the plankton very speculative, if not impossible. With the deficiency of day hauls made between the surface and 1000 M.W., and considering that no closing nets were used, a comparison of day and night collections cannot possibly be made. Table 9 gives the per­ centages in the positive hauls of all species studied in all positive Dana stations. The unexpectedly high percentages, often higher than 30 ‘’/o, in the tows deeper than 2000 M.W. seems incredible, especially since they usually yield only a few specimens. As shown in table 9 it is very probable that the specimens present in these tows are caught somewhere above the depths where the net is horizontally towed. The high percent­ age of such positive deep hauls might indicate that the tendency of phronimids to occur in shoals is depending on sight and therefore restricted mainly to the uppermost photic water layers while in greater depths they are mure evenly (listrit)uted. I’he Barbados collection provides some hints on the vertical migration of the phronimids. During the two year period, night hauls were taken from 100 M.W. and from the surface with closing nets, while the day hauls were taken from 500 M.W., 400 M.W., 300 M.W., 200 M.W., 100 M.W. and from the surface. Actual fishing depths are estimated from the angle of the wire. The catches of the phronimids are plotted by month against the estimated depth of capture in fig. 13. Among the day hauls, with only two exceptions, phronimids occurred below depths of 25 metres, while in the night hauls, they were often caught in the upper 25 metre layer, even up to the surface. The absence of daj’ records for May is probably due to the fact that only one day trip was taken in this month. It is apparent from this figure that diurnal vertical migration exists among the phro­ nimids, but the actual range of the migration might be much greater than the depth from which the collections are taken. Diurnal vertical migration probably is generally present in the pelagic amphipods, and has been shown to occur by H ardy and G l n t h e r (1935), B o u s f ie l d (1951) and B ary (1959 b) among cold water species. No seasonal variation of vertical distribution can be interpreted from fig. 13, nor from the CCOFI collec­ tions. B owman (1953) found seasonal changes in the catch of epipelagic hyperiids from the latter. Paratbe- misto pacifica, for instance, inhabits deeper water in March and November than in July, based on a comparison of day and night hauls. The mean number of catch per positive haul in the night collections was found to be live times greater than that of the day collection in March and three times greater in November, but there is jiractically no difference in July. B ow m an therefore suggested that, from the great difference of the catch Table 9. Percentages of phronimid species of the positive Dana stations 3681-4025.

M. W. scdcntaria atlantica solitaria paciftca abcab cabcab

50 ...... 32 78 41.0 37 57 64.9 9 28 32.1 28 40 70.0 100 ...... 39 95 41.1 40 68 58.8 9 31 29.0 25 47 .5:i.2 300 ...... 51 97 52.6 42 69 60.9 12 32 37.5 16 44 36.4 600 ...... 46 86 53.5 28 65 43.1 11 29 37.9 12 46 26.1 1000 ...... 48 82 58.5 17 60 28.3 5 29 17.2 5 40 12.5

1000 ...... 16 18 88.9 12 18 66.7 2 9 22.2 3 15 20.0 2000 ...... 19 28 67.9 15 26 57.7 1 11 9,1 10 19 52.6 3000 ...... 18 28 64.3 12 26 46.2 2 11 18.2 7 18 38.9 4000 ...... 12 22 54.5 7 2') 35.0 2 8 25.0 4 15 26.7 5000 ...... 4 8 50.0 6 , 8 75.0 0 3 0 3 4 75.0 6000 ...... 3 5 60.0 1 5 20.0 I 2 50.0 1 3 33.3

M. W. collelli curvipes stebbingi i-loiigata abcabcabcabc

50 ...... 21 33 63.6 18 42 42.9 11 21 52.4 20 42 47.6 100 ...... 16 41 39.0 27 54 50.0 12 22 54.5 28 49 .^>7.1 300 ...... 16 40 40.0 32 . 54 59.3 13 22 59.1 27 48 56.3 600 ...... 13 38 34.2 28 50 .56.0 8 22 S6.4 20 48 41.7 1000 ...... 7 33 21.2 8 45 17.8 6 21 28.6 7 42 16.7

1000 ...... 4 13 30.8 10 15 66.7 5 11 45.5 9 15 60.0 2000 ...... 7 16 43.8 6 21 28.6 5 13 38.5 14 23 60,9 3000 ...... 6 16 37.5 7 20 35.0 5 13 38.5 7 22 31.8 4000 ...... 4 14 28.6 3 16 18.8 5 12 41.7 5 18 27.8 5000 ...... 2 6 33.3 1 6 16.7 2 5 40,0 2 6 33,3 6000 ...... 1 4 25,0 0 4 0 0 4 0 1 5 20.0

a. number of positive hauls; b. number of positive stations and c. percentages of a in b.

between the day and night hauls in March and November, diurnal vertical migration is occurring during these months, and that during the day, part of the population inhabits water deeper than the depth surveyed by the CCOFl programme. In July, the population may ascend to a higher level and have very weak diurnal vertical movement, perhaps only within the upper 70 metres, i.e., within the depth of the CCOFl collection. The catch of phronimids, mainly Phroninui sedenlarki and P. ollnnlica, of the CCOFl collection does not reveal the seasonal change demonstrated by Parathemisto pacifica. The mean number of catch per 1000 m® of water strained ( B o w m a n , unpublished data) usually varied between 1 and 2 in the day anil night hauls of these months. No dilTerences are apparent in vertical distribution of the various sizes or stages. From the present study, it appears that the immature specimens generally concentrate in the upper layer, and as a matter of fact, in the larger species, e.g., Phronimn sedentnria and P. atlantica, they are dominant in number over the combined specimens of the other three periods. They, therefore, contribute the most important part in forming the general pattern of the vertical distribution shown in table 8. The adolescent and mature individuals seem to have a more or less random distribution in the vertical direction. In the Mediterranean (SrKi>HK.\si:.\, 1924), female Phronima sedentnria are distributed differently according to size in the summer. .Specimens of larger than 20 mm in size were nearly all taken with 300 to 400 M.\\'., the very young ones (4-7 mm) were caught chiefly at the surface, and specimens of intermediate size occurred both at the surface and deeper. D l dlicm (see p. 45) mentioned the vertical migration of Phronima sedcntaria and P. atlantica in the Mediterranean in connection with their propagation. This is somewhat contrary to S t e p h e n s e .n ’s findings for P. sedentaria. In the Thor material, all females with ova or embryos in the brood pouch were taken between 300 to 1000 M.W. (open nets). In the present investigation, the results of an attempt to determine the depth at which the phronimids spawn are not satisfactory. The females with ova or embryos in the broad pouch or with very well developed gonads and great brood lamellae seem to be distributed randomly in the range of the vertical

MONTH -► Fig. 13. Vertical distribution of phronimid-positive hauls in the waters off west coast of Barbados. Hollow marks, day hauls; solid marks, night hauls. ^ Phronima allantica. □ P. coUetti. o P. curvipes. 7 P. pacifica. 2 P. sedentaria. Phronimella elnngala.

Table 10. Showing the number of hauls at different depths (M.W.) containing female specimens.

M.W. sedentaria allantica solitaria paciflca abcdahcabcabc

()...... 0 0 0 n 0 0 0 0 0 0 o o o 50 ...... 0 2 0 0 2 3 2 0 0 0 4 6 0 lOO...... 1 1 0 0 4 6 1 0 0 0 2 1 1 300 ...... 4 9 5 2 3 12 1 1 3 0 2 2 1 600 ...... 4 11 1 1 0 3 2 1 3 0 0 3 0 lUOO...... 5 14 2 5 0 3 1 0 2 0 0 1 1

1000 and more ...1 7 2 0 0 1 1 1 0 0 2 1 1

M.W. colletti curvipes stebbingi elongata a b c abcabcabc 0 ...... 1 0 0 0 0 0 0 0 0 0 0 0 50 ...... 0 6 2 2 1 0 2 0 0 2 1 0 100 ...... 1 5 0 7 6 1 0 0 0 2 0 0 300 ...... 3 2 0 4 7 2 1 2 1 2 0 0 600 ...... 2 1 1 2 7 0 1 2 0 0 0 0 1000 ...... 1 2 0 0 4 1 0 0 0 0 0 0

1000 and more ... 5 3 0 2200 1 0000

Female specimens with (a) very well developed gonads and almost complete development of the brood lamellae, (b) with ova in the l)rood pouches, (c) with embryos in the brood pouches, and (d) juveniles. Fig. 14. Geographical distribution of P/i/-on(ma scdcn/an'a F o b s k a l . • Dana collection. + Non-Dana collections available for the present study. A Known records from the literature.

distribution of the species (table 10). The se.\ually indistinguishable juveniles of P. sedentaria are all found in hauls towed at 300 M.W. or deeper. This suggests that the phronimids may not necessarily have to ascend to the surface for propagation as was suggested by D udlich (1. c.). From the foregoing description, it is believed that the phronimids are epipelagic planktons. At night they ascend to the upper 200 to 300 metres, with the highest concentration at the depths between 20 to 100 metres, varying with the species and the locality. Generally they do not invade the top surface layer. A diurnal vertical migration does exist in the phronimids, but due to the gear used and the depths surveyed in the collections available for the present investigation, the actual range of the migration is impossible to determine. However, it is believed to be deeper than the epipelagic zone described by B r i ln (1957 b) and E kma.n (1953). E k.m.\n considered the epipelagic layer to comprise only the upper 150-200 M. B rl ln identified it as the photic layer proper, which varies from a thickness of 200 metres in the clear subtropical oceans to less than 100 metres in the seas with high productivity. Trom the present material as well as from the Thor collection, there is no evidence to support D u d lic h ’s speculation that the phronimids move towards the surface for spawning.

Geographical Distribution

The phronimids are all circumglobal species. Their geographical distribution is plotted on fig. 14-21. The positive Dana stations are marked in solid circles and those of the other materials available for the present study by crosses. The triangles denote the records of captiu'e from the literature. In some cases the findings are closely located or overlap each other, so they are unable to be shown on the maps. There are no records in the open Pacific Ocean, except those given by S t e b b in g (1888) and .St r e k t s (1877, 1882). The Pacific Ocean has not yet been proj)erly investigated. The lack of records for these waters \\ ill remain a problem until publication of the results of recent expeditions; for instance, until those of the Scripps Insti­ tution of Oceanography of the I’nited States are available. The geographical distril)ution of the jjhronimid species are described as follows; 1. Phronimn sedentaria. (Fig. 14). This sepcies is most abundant and has a range of distribution wider than that of any other species of the Phronimidae; it occurs in 202 out of the 224 Dana stations (positive) 8* for phronimids. In the Atlantic, it is distributed in the western part from 50° S to about 45° N, with a doubt­ ful rccord within the Gulf of St. Lawrence (B ol s f ik i.d , 1951). In the eastern part, it extends from the vicinity of the southern ti]) of Africa to the waters off the western coast of Ireland, with a few captures recorded further north: Shetland Islands, between Faroes and Iceland and southwest to Iceland. This range of di­ stribution, with few exceptions, falls within the area bounded by the 15° C isotherm in the north and 10° C isotherm in the south of the surface water in August and vice versa in February, or by the 10° C isotherms at 200 metres depth. It is one of the commonest species of hyperiid aniphipods in the Mediterranean, but is more al)undant in the western basin than in the eastern basin. It is scarce in the Adriatic and there are no records inside the Dardanelles. It also occurs inside the Caribbean Sea and the Gulf of Mexico. In the Pacific, only one record of the open central part is known from the past (S te b h in g , 1888). The cross­ section of the S. Pacific surveyed by the Dana yields only five positive stations in the central part. All the other records are more or less along the continents. Its distribution pattern is like that in the Atlantic, i.e., it penetrates to higher latitudes in the east than in the west of the Northern Hemisphere and vice versa in the Southern Hemisphere. In the western part of the Pacific, it is often taken from the waters around New Zealand, with the most southern finding near Macquarie I. It disappears in the waters northeast and north of Australia but appears again in Indonesian waters. It occurs further northward in the South China Sea, the adjacent waters of Taiwan, and finally stops in the area immediately south of Hokkaido. The northern j)art of the Kast China Sea and the Sea of Japan have been rather extensively investigated by the Japanese biologists (liUK, 1958 & 1959) but yield no captures. Hence, it can be stated with confidence that these areas are outside the distributional range of this species. In the eastern part of the Pacific, the most northern record was reported by T uorsteinson (1941). She stated that many specimens of 25-30 mm in length were collected in the (iulf of Alaska from depths from 1000 to 2000 metres but she gave no exact locality. From thence southward, it is occasionally caught off Vancouver Island, and young forms are regularly collected in the C.COIT stations soth of 45° N. It has been taken several times by the Dana inside the Gulf of Panama. The most southern record of the eastern part is taken from Longlinig station 9 at 4°28' S and 92°16'W. The range of (listril)ution in the Pacific is generally limited by the isotherms of 15° C in August and 5"^ C in February of the Northern Hemisphere and 10° C in February and 5° C in August of the Southern Hemisphere, or by the waters enclosed by the isotherms of 5° C at 200 metres depth. In the Indian Ocean, it is regularly collected along the route investigated by the Dana. It has also been recorded in the Arabian Sea, the Gulf of Aden and the Red Sea. The most southern records were reported by IlrKLEV (19B0 h ) between Australia and Karguelen, and south to Australia by S teb h in g (1888) and Vinogradov (1962). There is a wide gap between these southern stations and the positive Dana stations. The lack of records in this area is, as in the open Pacific Ocean, due to deficiencies in investigation. The southern limit of the distribution is bordered by the same isotherms as those of the S. Pacific. 2. Plironima allanlica. (Fig. 15). The geographical distribution of this species is generally in accord with that of P. sedentarin. The exceptions are listed below: In the N. Atlantic, the most northern findings are oil New England in the west and off Ireland in the east. In the Mediterranean, it is one of the most frequently occurring species and is distributed evenly over both the eastern and western basins ; it has been recorded once in the Aegean Sea at the entrance to the Darda­ nelles. There is no rccord inside the Gulf of Mexico. In the S. Atlantic, none has been captured in the western part south of C. de Sao Rouqe (5° S). In the Pacific, S t r e e t s (1882) gave the range of 37° N to 30°42' S , and 81°40'W to 160°25'W. Two captures were made in the central N. Pacific by Challenger. In the S . Pacific, it has been recorded rarely in the ajacent waters of New Zealand. In the Indian Ocean, it seems to be less abundant inside the Arabian Sea than P. sedentaria. Unexpect­ edly, it was taken by the German Antarctic Expedition at 65°57' S and 88°58' E, the most southern record of the phronimid species. 3. Phronima solitaria. (Fig. 16). This species occurs more or less together with P. sedentaria and P. atlan- tica, especially with the former (see p. 17), but has a much narrower geographical range, within the 40°- Fig. 15. Geographical distribution of Phronima allanlica G u e r i n . • Dana collcction. + Non-Dana collections available for the present study. A Known records from the literature. latitudes in all oceans. In the Atlantic, it is more abundant in the eastern half. In the western half, it has been taken in the waters adjacent to Bermuda, and between the latter and the American continent. It has been caught only once in the Mediterranean (Sti-;php:nse\, H)24). N'o records are known from the Caribbean and the Gulf of Mexico, but there is one catch by Dana from the Florida Strait. No records are found in the eastern half of the X. Pacific nor in the whole S. Pacific. Stebbi.ng (1888)

Fig. 16. Geoigraphical distribution of Phronima solitaria G u e r i n . • Dana collection. - Non-Dana collections available for the present study. A Known records from the literature. Fig. 17. Geographical distribution o t Phronima pacifica S t r e e t s . • Dana collection. + Non-Dana collections available for the present study. A Known records from the literature. has two records (Phronima megalodoiis) from the central N. Pacific. The most northern positive station in the inshore seas is north of Taiwan. In the Indian Ocean, except for one station southwest of Sumatra and two stations outside the Bay of Bengal, it completely disappears from the open waters investigated by Dana, it appears again along the African coast south of the Equator and continues to be present around the southern tip of Africa. It has been taken once in the Arabian Sea and once in the Red Sea by the John Murray Expedition (Barnard, 1937 b). Owing to the similarity in morphology' of this species with the two previous species, it may be misidentified in some cases, especially in the younger stages. The actual range of the distribution therefore may be wider than is recognized here. 4. Phronima pacifica. (Fig. 17). This species is again limited to the low latitudes. It occurs much more frequently in the east than in the west of the Atlantic. In the N. Atlantic, the most northern finding is by the Dana near 45' X. It has only been recorded by V o s s e l e r (in Lo Bi.wco, 1903) from Naples in the Mediter­ ranean. All captures in the Caribbean are from near the edge of the Atlantic. It has been caught one in the Gulf of Mexico near Yucatan Channel. In the S. Atlantic, the Dana material contains no captures south of ‘iO"" S, but it was caught once by the Discovery (B a r n .^r d , 1932), and also found in the southern sector of the African coastal water (S ie g f r ie d , 1963). The range of the distribution in the Atlantic lies within the area enclosed by the surface isotherms of 15“ C in the winter and 20° C in the summer, or by the 200 metre iso­ therms of 15° C in the north and 10° C in the south. In the Pacific, although the Dana Expeditions have made quite extensive collections inside the Gulf of Panama, these have yielded no specimens of this species. The only records in the eastern part of the Pacific are taken from two Longlining stations. Most are immature forms. In the open waters. S t r e e t s (1877) gave the range of 4°-21°X and 127°-151°W for this species but subsequently he extended this to 40° \ to 30°42' S and 97°14'-157°37' \V (1882). The latter range is doubtful since it also covers the area surveyed by the CCOFI programme, which yields not a single specimen in the collections available for the present investigation. This species generally lives very close to the surface, at least at night. Therefore it cannot be argued that the CCOFI collection is taken from a depth (70 m) loo shallow lo contain this sepcies. In the eastern part of the Pacific, it has been caught only once south of the Equator by the Dana. It occurs rarely in Indonesian waters but appears frequently in the South China Sea. The Fig. 18. Geographical distribution of Phronima collelli Bovallius. • Dana collection. + N’on-Dana collections available Jor the present study. A Known records from the literature. most northern positive station is northeast of the Phillippines, just south of 20° X. From Japanese reports, it can be stated with certainty that this species does not penetrate further north in this part of the Pacific Ocean. This species occurs fairly frequently where the Dana worked in the Indian Ocean. The most southern positive station is south of the Mozambique Channel. The species occurs inside the Red Sea (S pa n d l , 1924 b), but has not been caugt by the John Murray Expedition in the Arabian Sea. The isotherms for its southern boundary are 25° C in the summer and 20° C in the winter in the surface water, and 14° C at 200 metres depth. 5. Phronima coUetti. (Fig. 18). This species has the same pattern of geographical distribution as that of P. pacifica in the Atlantic. In the Mediterranean, Stephensen (1924) reported findings from 15 stations in the western basin. These included, however, many males of P. curvipes, which although they have been mentioned in the literature have never been fully described. After re-examining the Thor material, the posi­ tive stations are reduced to five and all are located west of Sardinia. The only record in the Caribbean Sea is in the Barbados collection which is from the offshore waters of Barbados on the Caribbean side. No capture is known from the Gulf of Mexico. The geographical distribution in the Pacific is very different from that of the last species. It has been found occasionally in the outer stations of CCOFI collections south of 35° X and very abundantly in the Longlining stations. In the waters adjacent to Japan, it has been caught on several occasions on the Pacific side. The most northern occurrence is at 41°58.5' X and 154°14' E. There is no record from the South China Sca. It has only been found twice in the seas adjacent to the Indo-Malay Archipelago from the Dana material, but PiRLOT (1930) reported several positive findings from the Siboga collection in the same area. The northern limit of the distribution of this species lies just inside the 20“ C isotherm of the surface wafer in August and 10° C in February, or at the 10° C isotherm at 200 metres depth. This species occurs almost co-extensively with P. pacifica in the Indian Ocean. The differences are that it does not exist inside the Red Sea but is known within the Bay of Bengal (G iles, 1887, as P. biicepha}a). 6. Phronima affinis. Only two records are known from the literature, both are male. Vosseler’s (1901) type specimen w^as taken from 31.3°X and 47.7°W, and P iri.o t’s (1929) doubtful juvenile male was taken from the waters between Azores and Madeira. 7. Phronima ciiruipes. (Fig. 19). The distributional pattern of this species in the Atlantic is again similar to that of P. pacifica, but it is almost entirely absent from the western part of this ocean. In the Mediterranean, Fig, 19. Geographical tlistribulion of Phronima curvipes V o s s e l e r . • Dana collection. - Non-Dana collections available for the present study, A Known records from the literature. it occurs (among the Phronima species) only less frequently than P. sedenlaria anc P. allanlica, but unlike these two species, it is limited within the western basin of this sea, near the Atlantic. It also occurs in the Caribbean Sea, but rarely. In the western part of the Pacific, it occurs only in the very low latitudes. There are records from the Gulf of Panama and from the Longlining stations. There are two positive Dana stations north and northwest of New Zealand. It is occasionally found in Indonesian waters but frequently caught in the South China Sea. The most northern positive station is north of Taiwan. No record has ever been reported from the waters in the vicinity of Japan. The distribution in the Indian Ocean of this species resembles that of P. pacifica in the open water. In the coastal water of eastern Africa, it penetrates further southward than the latter. It is not known to occur in the Red Sea or the Arabian Sea.

8 . Phronima slebbingi. (I'ig. 20). V o s s e l e r (1901) and M ogk (1927 b) have stated that the present species occurs most often together with P. sedenlaria. The reason for this statement is that both authors worked on material collected from the Atlantic. P. slebbingi occurs very frequently in the Atlantic within the 40° lati­ tudes. It has been recorded twice in the Mediterranean (Chevreux, 1913 and the Dana collection). Both records are in the western basin. In the Caribbean Sea, it is found at Mona Passage. This species probably is absent from the Gulf of Panama where several Dana stations are located. In the CCOF'I collection, several specimens are present. The most northern one is from 42° N. H urlkv (1956) also found this species in this area. In the S. Pacific, it has been caught from the surrounding waters of Tonga and Fiji (H u r l e y , 1960 a). In the eastern X. Pacific, it occurs in the East China Sea and the Pacific south and east of Japan. It was found only once in the South China Sea and is unknown from Indonesian waters. VINOOR.VDOV (1962) recorded it once from the southern Indian Ocean southeast of Australia. This species seems to be rare in the Indian Ocean. It has never been known from these waters except for one mentioned by Vinogradov. In the Dana material, it appears only west of 65° E but never is abundant. 9. PhronimeUa elongala. (Fig. 21). The present species occurs frequently in the Atlantic, but generally less frequently in the very western part. The northern limit of the distribution lies approximately within the latitude of 45" X. In the Mediterranean, it has been recorded from both western and eastern basins, but more frequently in the former. It occurs in the Adriatic but not within the Aegean Sea. It is present in the Fig. 20. Geographical distribution of Phronima slebbingi V o s s e l e r . • Dana collection. + Non-Dana collections available for the present study. A Known records from the literature.

Barbados waters of the Caribbean side and also found at Mona Pa.ssage. In the S. Atlantic, most of the findings are located in the open ocean. It is absent in the Gulf of Guinea, which has been investigated by the Dis­ covery (B.\r n a r d , 1932) and the Atlantide (R e id , 1955). Challenger recorded few captures off S. America. The southern limit for this species perhaps will not extend beyond 40° S. This species is not present in the Dana collection taken from the Gulf of Panama. It has been found twiec

Fig. 21. Geographical distribution of Phronimella elongala C l.v u s . • Dana collection. + Non-Dana collections available for the present study. A Known records from the literature. from the CCOFI collection, the most northern finding in the eastern Pacific is south to 45° N. The Longlining stations have this spccies present frequently but usually in small numbers. The records known in the open Pacific were reported by S t r e e t s (1877 & 1882) and S te b b in g (1888). S t r e e t s in his second paper gave the range of distribution in this area as from 34°0()' N to 30°40' S and 102°43' W to 150°00'W, based on seven specimens captured. The only record from the S. Pacific was reported by B.^rnard (1930) from the sur­ rounding waters of Three Kings Islands. The Dana Expedition 1928-1930 failed to take any specimen of this species when crossing the Pacific Ocean and surveying the waters from the vicinity of New Zealand to the north of Australia. It is caught frequently in Indonesian waters, the South China Sea, the East China Sea and the Pacific Ocean southeast of Japan and south to 35° \ . In the Indian Ocean, its tlistribution is most similar to that of P. colletti. In addition to the Bay of Bengal, it also occurs within the Arabian Sea but not in the Red Sea. The German Antarctic Expedition had records from the open seas and unexpectedly also from the southern Indian Ocean at 63°42' N and 82°00' E.

Zoogeograph}^

The planktons are passively drifting organisms, and therefore components of the water medium itself. With the existing current system of the oceans, the continents form practically no physical obstacle to the distribution of the marine animals, if the latter could tolerate the different evironmental condition of the various parts of the oceans. Temperature might serve as a checking mechanism for the survival and/or reproduction of the species. Oceanic species are very sensitive to the salinity change. The fact that neither isotherms nor isohalines will satisfactorily indicate the marine distribution shows that temperature or salinity alone would not effectively limit the dispersal of the marine animals. It has been realized that water masses, which have their unique characteristics of temperature, salinity, oxygen, nitrate, phosphate, etc., are the environmental units for the marine distribution. Since the salinity-temperature characteristics are easier to defcrmine than the other fundamental properties of the water masses, they are frequently used for this kind of study. PiCKFORD (1946) was perhaps the first to relate the distribution of the marine animals to the water masses. A similar relationship has since been shown for plantons (B a r v , 1959 b; B r in t o n , 1962) and for llshes (H a f f n e r , 1952; E b e l in g , 1962). The fact that marine species are highly related to the water masses is used to demonstrate the intrusion of different waters in a mixing zone. This, as D unbar (1963) remarked, ■'. . . can be looked upon as a return in kind, from the biologists to the physicists, of help received in the past by the biologists from the physicists.” The geographical distribution of the phronimid species described, is found generally to be in good agree­ ment with the distribution of the water masses and boundaries. A view of the maps (figs. 14-21) of the geographical distribution of these species, with the e.xception of Phronima sedentaria and, perhaps of P. ntlnntica, shows that their occurrences generally cease at the latitude of 35°-40° \ in the western part of the X. Atlantic, where the Subtropical Convergence is located, and where the Gulf .Stream runs easterly to be continued as the N. Atlantic Drift. The positive findings of the specimens usually extend somewhat northward in the eastern part of the N. Atlantic. This again is in good agreement with the hydrological conditions in this part of the oceans. The N. Atlantic Drift runs north-easterly and the Atlantic Central water also spreads further north in the east than in the west. A part of the \ . Atlantic Drift, after crossing the mid-Atlantic Ridge, turns south off the coast of Spain as the Canary Current. The phronimid species, except for the two above­ mentioned ones, are entirely absent from the Bay of Biscay. This pattern of distribution can be explained by the fact that these species are warm water species, and cannot tolerate the colder temperature by going further north. This boundarj- of the warm water species in the X. Atlantic has already been noticed by the zoogeographcrs. However, it is not so pronounced as the corresponding one in the southern hemisphere, owing to the fact that the convergence is less marked and less continuous in the north (E kma.\, 1953: 325). Only Phroninin sedentaria, P. atlantica and Phronimella elongata occur in both the eastern and western basins of the Mediterranean. All the other five species examined in the present investigation and also those from the known records in the literature are entirely resticted to the western basin, and except for Phroniiiui curvipes they are, as a rule, rare species. The smaller numbers of pelagic amphipods in general in the eastern part of the Mediterranean are si own pronouncedly in the Thor collection, from which S t e p h h n s e n (1924) has found that of those species occurring in both basins, the catch per haul was usually higher in the west. He also found that there is a slight ditlerence in the fauna of both regions. Fourteen of the sixty-eight species in the western basin are not caught in the eastern basin, while twelve of the sixty-six eastern species are excluded from the western fauna. The cause of the quantitative and qualitative differences of the fauna in the two parts of the Mediterranean is not known, but the water is more productive in the west than in the east. Tno.MSE.v (1931) fovind that the concentrations of phosphate and of nitrate are apparently higher in the western basin. In the Caribbean area, only P. sedentaria, P. atlantica and P. curvipes have been found but rarely within the sea, and there is practically no rtcord for P. solitaria. The other four species are known to occur at the passages between the Caribbean and the Atlantic. Their appcarance in these waters, therefore, might be due only to accidental incursion of the Atlantic population; since the plankton community within the Caribbean has not been well studied, and the Dana only took a few stations there, this conclusion is more or less specu­ lative. Only two species are recorded from the Gulf of Mexico, P. sedentaria from the coastal water near Louisiana and P. pacifica at the Yucatan Channel between the Caribbean and the Gulf. In the S. Atlantic, the southern boundary of the distribution of the phronimids is limited more markedly by the Subtropical Convergence. Of the eight species studied, only P. sedentaria has been found south of this boundary. This is to be expected since P. sedentaria also occurs beyond the convergence in the north. The more numerous findings of all species in the eastern than in the western part of the S. Atlantic is partly due to the more frequent investigations that have been carried out in the former area, and perhaps is also due to the poorer organic productivity in the west than in the east, (F le m in g and L a e v a st i , 1956). It has also been found through the Dana collection that macroplankton abundance is very high in the northeastern part of the S. Atlantic (J e s p e r s e n , 1935). In the Pacific, the distribution patterns of the phronimids are not well known, although the general prin­ ciples described for^the Atlantic fauna may also be applied here. The subtropical convergences in the X. and S. Pacific at the latitudes^of 40°-45° form the most effective barriers for the distribution. These convergences have already been shown to be barriers of other warm water planktons. Good examples are illustrated in the papers by Bieri (1959) and Bri.ntox (1962). In the X. Pacific, no phronimid species except P. seden­ taria is found north of the subtropical convergence. The findings of P. sedentaria in the waters oil Vancouver and in the Gidf of Alaska are similar to its appearance in the waters ofl' Shetland Islands, between Faroes and Iceland and southwest to Iceland in the X. Atlantic. This is mainly due to the transport by the drifts northeasterly across the northern oceans. In the transitional zone of the eastern part of the X. Pacific, all but P. solitaria, P. pacifica and P. curvipes are present in the CCOFI collection. Of those present in this region, P. stebbinqi, P. colletti and Phroniinella elongata occur rarely and are found chiefly in the waters south of 35° X. Of the last three species all the findings north of 40^ X, and most of the remainder are taken by the July cruise. The presence of these three species in this transitional water how ever, seems ot be a puzzle. According to ^^'vRTKI (1966) the intertropical convergence periodically shifts north and south in the eastern Equatorial Pacific and is located in a northerly position at, or north of 10" X during the months of .\ugust to December. The timing of this northerly shift is not in good accord with the present findings of the specimens, but it still indicates that the fauna of the lower latitudes may invade northern areas regularly through the facility of favourable current systems. B ow man (1953) has defined twelve species of epilagic hyperiids as subtroj)ical fauna, bounded at the north by isotherms af about 15-18“ C (at 3(1 M.); this is a further subdivi­ sion of K k m a n ’s warm-water species. The present records of these three species are thus included in this fauna from the point of view of the isotherms. All the species, excejit P. solitaria occur at the Longlining stations in the equatorial water of the eastern Pacific. Of the phronimids found in the S. Pacific, only P. sedentaria and P. atlantica occur south of the Subtropical Convergence. The presence of these two species in the waters southwest of Xew Zealand is possibly a result of the West Wind Drift. This may be further substantiated by their distribution patterns in the Indian Ocean. Salinity (XJ a. Atlantic Ocean.

Salinity (%J b. Indian Ocean. Fig. 22. The distribution of Phronima sedentaria ForskAl in the water masses. The water-mass envelopes are after Sver- Satinity(%J c. North Pacific Ocean.

15

34.0 3 4 .5 35. 0 35.5 Salinity (XJ d. Soutli Pacific Ocean. DRup et al (1942). The fine lines are T-S characteristics of the positive stations below 100-150 metres to about 500 metres. All species are present in the Indonesian waters, but only P. padfica and P. stebbingi are found in the Sulu Sea. All but P. colletti occur in the S. China Sea. F ace (1960) also found that three oxycephalid species, Streetsid steenstriipi, S. inindanaonis and Rhabdosoma nnnor are also only taken from the Sulu Sea and S. China Sea but are absent from the other Dana stations in the Indonesian waters. This pattern of distribution can be interpreted from the hydrological situation. The renewal of the Sulu Sea water is from the S. China Sea, whereas the remainder of the Indonesian waters derive from the adjacent Pacific waters (S v e r d r u p et al, 1942: 737). In the Indian Ocean, the southern boundary for the phronimids again is the Subtropical Convergence. However, in addition to P. sedentaria and P. atlantica, P. stebbingi and PhronimeUa elongaia have also been recorded once south of the convergence. These are very unexpected findings for the last two species, since they never occur outside the Subtropical Convergence in the central waters of both the Atlantic and the Pacific. The fauna inside the Bay of Bengal has still not been properly investigated. Only Phronima colletti and PhronimeUa elongata arc recorded inside the Bay. On the other hand, the Red Sea and the Arabian Sea have been moderately explored by the John Murray Expedition and the Polar Expedition. Four species are known to occur within the Red Sea: Phronima sedentaria, P. atlantica, P. solitaria and P. pacifica. The first two species as well as PhronimeUa elongata are found in the waters of the Arabian Sea. The catch of Phro- nima atlantica and PhronimeUa elongata by the German Antarctic Expedition from the Antarctic Ocean south of the Subantarctic Convergence is very peculiar. There have been many oceanographic expeditions exploring the subantarctic waters, and no other phronimids have been found south of 55° S. It is there­ fore believed that the discovery of these two species from such an area can only be considered as an accidental occurrence through the transport of ephemeral ocean currents. In the section on vertical distribution it was shown that, except for P. sedentaria and P. curvipes, all species usually occur at depths of 100 M.W. or shallower at night. Since their vertical ranges are not established from the present studies or from the literature, it would seem presumptuous to plot the T-S characteristics of these species on water-mass envelopes in order to better interpret their distribution. The difficulty results from the fact that the T-S characteristics of the surface waters (where the animals live at night) overlying the main masses are very variable from one locality to another, and are too much alTected by surface currents and the exchanges between the water and the atmosphere. The thickness of the surface layer varies from 100 to 200 metres over the equatorial and central water masses, and these two water masses have approximately the same geographical extent as do the distribution ranges of most of the species studied. It is obvious that T-S curves of most of the species studied would lie outside the narrowly defined water mass envelopes, and therefore would not provide significant explanations of distributions. P. sedentaria is found at night at depths of 100-300 M.W. For this reason and because of more available data for this species and assuming that it may descend to 500 metres during the day, the T-S characteristics of P. sedentaria may be plotted for the posi­ tive stations where hydrological data are available (S ch.m id t, 1929; T h o m s e n , 1937; J o h n st o n 1937; Dis­ covery Committee 1929; University of California 1949 a and b, 1950 and 1951), and superimposed on water mass envelopes (fig. 22) following the method used by E b e lin g (1962). For the other seven species, it is reason­ able to suggest that they may descend downward into the water masses underlying the surface water. The distribution of the phronimid species as related to the water masses in the open oceans may then be given speculatively as follows: Phronima sedentaria: X. and S. Atlantic Central, western N. Pacific Central, Pacific Transitional, western S. Pacific Central, Pacific Equatorial, Indian Equatorial, Indian Central and Subantarctic. Phronima atlantica-. Same as Phroninm sedentaria. Phronima solitaria: X. and S. Atlantic Central, western N. Pacific Central, Indian Equatorial and Central. Phronima pacifica: Same as P. solitaria, with the addition of Pacific Equatorial. Phronima colletti: Same as P. pacifica, with the addition of Pacific Transitional. Phronima curvipes: Same as P. pacifica, with the addition of western S. Pacific Central. Phronima stebbingi: Same as P. colletti, with the addition of western S. Pacific Central. PhronimeUa elongata: Same as Phronima stebbingi. V. DISCUSSION

The family Phronimidae is made up of two genera with nine species, of which eight belong to the genus Phronima, and one to the genus Phronimella. The confusion of systematic status of the phronimid species in the past resulted mainly from their miu ked sexual dimorphism and the greater similarity of females of different species than of the males and females of the same species. V o s s e l e r (1901) definitely distinguished the males of Phronima sedeittaria and P. at- lantica as belonging to two species. Early taxonomists (C l a l s , 1872 a ; C h i n , 1889 b, 1895) thought they were the same species, P. sedentnria, because the former with rudimentary second antennae, was thought to he the juvenile stage, and the latter with fully developed second antennae was naturally assumed to be the adult. V o s s e l e r ’s morphological distinction was further substantiated by a successful rearing experiment in aqua­ ria (D u d lic h , 1926).

Of the males among the Phronima species, V o s s e l e r (1. c.) has described P. affinis as also possessing rudimentary second antennae in the nature male. Thev alidity of this species is, admittedly, in doubt for only the male is known and no more records have been reported since its discovery except a “doubtful” juvenile male (P ir l o t , 1929). Phronima solitaria raises another problem. The original discoverer (Gieri.n, 1836 a) and subsequently B o v a lliu s (1889) recognized it as a genuine species. V o s s e i . e r (1901), by comparing its morphological characteristics with P. sedentaria and P. atlanlica, considered it to be a variety of the latter. Since then it is listed as Phronima atlanlica var. solitaria by subsequent workers. The sense in which Vosseler assigned this as a “ variety” of P. atlanlica seems to be that of an individual variant. However, as has been pointed out earlier (p. 17) in the description of this form, there is no evidence in the whole course of its growth that mor­ phologically this species can be considered to be more clearly allied either to P. atlanlica or P. sedentaria. Geographically, P. solitaria usually occurs together with the other two species (p. 17) but is more restricted to the low latitudes (p. 56). It is therefore not a geographical variant of either of these. A search for cytological evidence by attempting to determine chromosome numbers in the oocytes was not successful in the present investigation; presumably cell constituents have been greatly altered by long preservation (more than 30 years) in alcohol. The failure to find males of this species from the immense collection of the Dana material suggests that P. solitaria might be a discontinuous phenotype of other Phronima species, possibly of either sedentaria or atlanlica. Genetic polymorphism (or “morphism” as preferred by Hixlkv, 1955), commonly occurs in the animal kingdom. A list of the literature has been given by Mayr (1963). The morphism that is so often present, according to Huxley (I.e.), is due to ambivalent mutants, inversion and translocation, variations in chromosome-number and -type, meristic discontinuity due to genetically-determined dilTerences, and high variability under certain circumstances. The morphs, i.e., the variants that contribute to mori)hism as defined by Huxley, may coexist within a single interbreeding population but may each be adapted to, and enjoy differential survival in, one distinct set of conditions confronting the species, or one habitat of the m any available (H u x ley , I.e., p. 5). The presence of the morphism is beneficial to the species in the sense that it m ay occupy a w ider range of environm ent conditions, while m aintaining gene flow between difTerenti- ally adapted members of the population. From their geographical ranges it might perhaps be concluded that P. solUaria, if it were a morph of sedentaria or allantica, is less tolerant of the cooler water of the higher lati­ tudes, i.e., beyond the area enclosed by the Subtropical Convergences. The suggestion that this form is a morph of some other Phronima species is admittedly speculative rather than decisive. To test the suggestion, more observations based on cytological, physiological and ecological experiments should be made. This also applies to the suggestion that this form might be a hybrid of the other two Phronima species, sedentaria and atlantica. It has already been mentioned that this species occurs most often where both P. sedentarki and P. atlantica are present. In conclusion since no concrete evidence is available to support the suggestions that P. snlitaria is either a morph of P. sedentaria or P. atlantica or a hybrid of them, it is suggested that P. solitaria should be entitled to full species rank until further observations setUe its status. It has been confusing to the taxonomists in the past that some Phronima species are only known as females in the literature. For instance, in addition to P. solitaria, there are no definitive descriptions for the males of P. pacifica and P. ciirvipes, although some incomplete diagnoses (S t r e e t s , 1877; V o s s e l e r , 1901; M o g k, 1927 b) and doubtful records (B a r n a r d , 1930: W a l k e r , 1909) are found in the literature. In the present investigation, it is found that this may be due mainly to the high degree of similarity of the males of these two species to each other and to P. colletti. The diagrams given in V o s s e l e r ’s monograph for the male of P. coUctti are believed in fact to be based on a specimen of P. pacifica (p. 22), thus confusing the later taxono­ mists. The distinction of the males of these three species is made possible from the present study, not only through a few distinctive morphological differences of certain structures (the carpus 5, the second uropod) hut by tests with a discriminant function based on several numerical characteristics of various parts of the body. .More importantly, the distinction is based on the geographical distribution of the female specimens of the corresponding species. Therefore the speculation by M ogk (1927 b) and B a r n a r d (1930) that P. colletti and P. pacifica might be two morphological forms (morphs?) of the same species, the former being the “normal” and "dominant” type, cannot be substantiated by the present investigation. Specimens of the PhronimeUa genus are very fragile and usually are broken in the massive samples. Detailed observation on this species is therefore impossible. From the limited data available from the present study, it seems that there is only one species, P. elongata, in this genus, although V o s s e l e r (1901) suggested that more than one is probable. The knowledge of the life history of hyperiid amphipods is inconsiderable, although limited information is available from the literature. Clearly only an incomplete picture of certain aspects can be given from study of preserved specimens. The pattern of the postnatal growth of the phronimid species can, however, be traced from the young within the brood pouch to the completion of sexual maturation. Amphipods are epimorphic, i.e., by the time of hatching, the segmentation is already complete. The postnatal development of the phronimid species is divided into four major periods - juvenile, immature, adolescent and mature - according to the state of sexual development. In each of the four periods, there are a number of stages which vary with the species, the different sexes of the same species and also with the j)eriod of the same species. The stage is recognized in the present study by the podomere number in the exopodite of pleopod 3. K ane (1963 a) first discovered that the podomere number in the pleopod rami is a good indicator of moulting stages of the hyperiid amphipod, Parathemisto gaudichaudii. The present observa­ tions further substantiate her discovery. It is believed from the close relationship between the increase in the number of podomeres and the increase in size and change in morphologj- of the individual, that this relation­ ship is not only speculative but has real meaning. This relationship is more constant in the younger stages than in the adult. When the individual approaches full maturation, the increase in the number of podomeres appears to be irregular. It is observed that before the segmentation of the exoskeletion of the pIeoi)od rami takes place, the inner tissue may have segmented already in the larger specimens. That the moulting stage can be judged from the segmentation of the appendages is not a new observation in the amphipods. S ex ton (1924) pointed out that the segment number of the second antennae in Gammarus chevreuxi shows the instar number of the animal. Her conclusion came from observation on living material and is therefore believed to have particular value. Since the present observations are based on preserved material only, it cannot be ascertained whether only one or more moultings occur between two successive stages. The postnatal development of the phronimids differs very significantly in the four periods defined by the present study. In the juvenile period, there is no sexual difference at all. The primordium of the gonad is small and the gonadal ducts are invisible. Among the amphipods, it is known that the reproductive organs may be undifferentiated at hatching and during the first intermoult periods (C h a r m a l x -Co t t o n , 1960). The lack of differentiation of the gonads has also been observed in terrestrial isopods in the young stages,

(L egrand and V a.ndkl 1948). In the immature period, sexual differentiation in the phronimids can be judged from differences in development pattern of the antennae. Other secondary sexual characters are not apparent, and males and females of the same size (or the same stage at this period) resemble each other in general body structure. The most significant development at this period is the increase in size. The size difference between individuals of different species and between the male and female of the same species mainly depend on the number of stages through which they pa,ss during this period (compare tables 3 and 4). The extending of the immature period not only results in a larger final size but may also favour the wider distribution of the species. The last speculation may be justified by the fact that both Phroninm sedenlaria and P. atlaiilica have a much wider range of distribution than the small species, e.g., P. collelli, P. pacifica and P. stebbingi. It has already been emphasized by E k m a n (1953; 73 and 239) that the length of the planktonic larval stage plays an important role in the dispersion of the .shelf fauna. This is possibly also true for the plankton fauna. The fact that the phronimid species of smaller size are distributed only within the Subtropical Convergences, is perhaps connected with the fact that marine poikilotherms in warm waters reach full maturation more rapidly than those in colder waters (D unbar, 1957). The adolescent period is generally very short, only one or two stages, among all phronimids. This period seems to be important for the preparation of the final completion of sexual development. For instance, the testes enlarge, the vasa deferentia become apparent and the seminal vesicles appear. In the female, there is further development of the gonads, and also the budding and growing of the oostegites. The full secondary sexual characters as well as the gonads appear to be suddenly complete at the time between the adolescent and mature periods. The different rates of the development of various characteristics described in the chapter on life history suggest that hormonal control, either quantitatively or qualitatively or both, may be present at critical stages of the different periods. (Teissier, 1960). It is believed that in general the phronimid populations continue to breed in all seasons. This is based on the following facts: among the Dana collection, propagating females of all specie.s are very frequently present; for P. allantka, no mature specimens have ever been found in the Barbados material, but propagating females are present in all cruises of the CCOFI collection available for the present investigation; and the breeding females of P. sedenlaria have either been reported in the literature or found from the Dana collection in the Mediterranean at all times of the year except for October. It is also believed that each individual female of the phronimid species may have more than one brood during her life span. This speculation is mainly based on the discoveries that the female moults after discharging her embryos and that the ovaries and ovi­ ducts recover after the spawning. That propagation occurs throughout the year seems to be common among the warm-water planktons. Many hyperiids from the Barbados collection are also found to bear young the year round, e.g., species of the genera, Telrathyrus and Poratyphis (unpublished observation). Go od- uoDY (1965) has noted that continuous breeding takes place in the populations of a mysid, Mysidium coluinbiae in mangrove lagoons and a mole crab, Enierila portoricensis in alluvial sands in Jamaica. It is generally assumed that year round propagation among warm water species occurs because the waters which they inhabit have insignificant annual variations as compared with the cold waters. However, M o ore (1949) has found that although the abundance of plankton in Bermuda waters shows little seasonal volume change, some species of the zooplankton exhibit fairly well-defined breeding periods, though these occur at different limes of the year. Among the amphipods, there is much evidence that some species produce more than one brood (S exton and M.a.t t u e w s , 1913; B legvad, 1922) and that some produce only once (S e g e r s t r .Il e ,

1950). Other examples are found in D lnbar (1957) and B o w .man (1960). D l .nbar found that females of the arctic hyperiid, Parathemislo libellula, breed only once through the whole life. B owman discovered new groups of eggs developing in the ovigerous females of the boreal hyperiid, Parathemislo pacifica. From the foregoing statements, the conclusions that phronimids spawn year round and that each mature female may spawn more than once in its life time seem to be very plausible. The feeding habits of the phronimid species, as determined from gut contents, and the morphology of the mouth-parts and other appendages, are omnivorous in character. The lack of long setae except on the pleopod rami and the strong denticles on the cutting plates of the mandibles suggest that they are unlikely to be filter-feeders. However, L ockhead (1963, in discussion after D ahl) has warned that undue emphasis must not be placed on the need for particular setae or other structures to transport or push the food forward to the mouth under the labrum. It is usually difficult to analyse the vertical distribution of plankton samples taken by non-closing nets. The analysis of the Dana material which is taken by non-closing nets and from different depths at night and during the day, poses another difficulty. The lack of tows from the same depths taken at night and during the day precludes reliable data for comparison. Determining the range of the vertical distribution and migra­ tion is therefore impossible. It has already been pointed out that there is a great chance to catch specimens in nets as they are being raised and lowered during the day hauls. The present investigation is therefore forced to concentrate attention on the night hauls, which are believed to give better results after substracting the pos­ sible catches in the upper waters from the total catches of hauls at a given depth. The very low percentage of the positive surface hauls (table 9) apparently demonstrates that the phronimid species generally avoid the very surface. It is found that Phronima sedentaria usually has the highest yield at 100 and 300 M.W., and the other phronimid species, at 50 and 100 M.W. Generally speaking, the immature individuals are mainly taken at shallower depths. Young phronimids and other hyperiids usually occur in the surface water (Dl dlich, 1926; Bigelow, 1926). The abundance of food in the surface layer may be the primary factor. The adolescent and mature individuals are distributed more randomly within the range of the catch. This pattern of distribution shows that these older individuals may have a greater ability to migrate vertically. The presence of the diurnal movement among the phronimid species is apparently demonstrated by the Bar­ bados colection (fig. 13), but its range is unknown. Hardy and G unther (1935) have found that Paratbemisto gaudichaudii may have a vertical range of 1000 metres in the waters of South Georgia. The epipelagic zone, according to B rlun (1957 b) coincides with the photic zone of the water. It may be therefore 200 metres in depth in the clear subtropical water or 100 metres in waters with upwelling and high productivity. Ekman (1953) has more or less arbitrarily defined the upper 200 metres as the epipelagic zone. From the Dana material (table 8), it is found that Phronima sedentaria and P. atlantica may occur at night as deep as 1000 M.W., and the other phronimid species at a depth of 600 M.W. Therefore, the lower depth of the vertical distribution of phronimids must exceed the epipelagic zone as defined either by Bruun or Ekman. If we take the average range of the vertical migration, 100-200 metres, for the most planktonts (Raymont, 1963), then the lower depth of the vertical distribution during the day may be 400-500 metres for the first two species and 300-400 metres for the remainder. These estimations may be too conservative as judged from the day hauls. B rinton (1962) also recognized a deeper range for the epipelagic euphausiids and found it is related to the depth of the water masses inhabited. He has defined the bathymetric and latitudinal zonation of associa­ tions of euphausiid species in mid-oceanic profile in the N. Pacific (I.e., fig. 102). No attempt is made here to elucidate the different depths of vertical distribution of phronimid species in different waters, which would rest on too many speculations to be reliable. Based on the estimated depths of the vertical distribution, the geographical distribution of the phronimid species is related to the water masses of the oceans (p. 66). It is becoming evident from the accumula­ tion of knowledge on distribution of the marine animals that water masses, which have their unique charac­ teristics, are the zoogeographic units for the marine plankton. The definition and distribution of water masses are given by S v e r d r u p et al (1942). Their role in zoogeography has been discussed in a number of papers, but from the more recent discussions, the works of E bellng (1962) and J o h n so n and B r in t o n (1963) are recommended. B e k lem ish ev (1966) has recently pointed out that in the open ocean, vortices of the order of magnitude of 1000 Km seem to be the smallest possible size for an oceanic plankton community. He con­ cludes that the large gyres extending from coast to coast enclose the primary water masses as well as the primary pelagic communities, e.g., the central water masses and their plankton communities. The convcrgcnccs and the divergences, which are the boundaries of the water masses, with their abrupt changes of the water characte­ ristics, e.g., temperature and salinity, are also the most effective natural boundaries for the distribution of the marine animals. The eight species of phronimids studied with the exception of Phronima sedentarin and P. atlantka, have their geographical distributions profoundly limited by the north and south Subtropical Convergences. From the incomplete records from the Pacific, all phronimid species are entirely absent from the area underlain by the Eastern Pacific Central Water mass. This is approximately the same area defined as the Hast Pacific Barrier by E kman (1953, p. 72) for the littoral fauna. Of course, a barrier for the littoral fauna may not necessarily be the barrier of the pelagic planktonic fauna due to the different requirements for the dispersion of the populations. It is however interesting to know from B r in t o n ’s (1962) comprehensive work on the Pacific euphausiids that, at least Thysanopoda aequalis is almost wholely limited to the Eastern Central Water, while T. subaeqiialis lives mainly in the Western Central Gyral. If we consider the distribution with regard to the morphological variations, more striking facts of the zoogeographical distribution are revealed. These variations are: (1) the long and short forms of the antenna 2 in the males of Phronima sedentaria; (2) the E. Pacific, the Indo-W. Pacific and the Atlantic forms of P. coUetti; and (3) the Atlantic and the E. Pacific forms of P. stebbingi. It is known from table 1, that male and female specimens of P. sedentaria taken from different parts of the oceans may have some characters significantly different from each other. These differences however do not show any regular and geographical trend of changes defined as a dine by H l' x lev (1942). Since the form of the specimens changes with age, the comparison of numerical characteristics is made difficult. The form of the male second antenna, however, provides an excellent example to show the definite separation of morpho­ logical characters between the specimens taken from the Western Pacific-Indian (long form) and the Atlantic- Eastern Pacific (short form), with the boundary located in the waters south of the African continent. Both females and males of P. colelti, unlike those of P. sedentaria, have shown distinct geographical varia­ tions. It is noticed here that variation also occurs between the specimens taken from the Atlantic and the E. Pacific. Only very few specimens of P. stebbingi are taken from the Indo-W. Pacific region. Of the specimens caught in the Atlantic and the E. Pacific, striking differences are found in certain characteristics.

E kman (1953, p. 326) has suggested that the ocean currents south of Africa between the Atlantic and the Indian Ocean are a means of transport for the circumglobal tropical species. Although this might be true for some species it must not be considered to be a general phenomenon for every species. B owman (1953) has already pointed out the possibility that little or no exchange of gene flow occurs at present between the Atlantic and the Indo-W. Pacific populations. From the first two examples of geographical variations found in the present investigation, B o w .man’s view is substantiated. The natural barrier for the gene How between the populations of the warmwater species of either side is likely to be the Benguela Current which is a cold oceanic current flowing north along the west coast of Africa. Judging from the abrupt change in the mor­ phological characteristics, the barrier must be very effective. The last two examples of geographical variations demonstrate that P. colletti and P. stebbingi are poly­ typic species. Polytypic species are not infrequently found in marine animals, and many references are avail­ able for, e.g., molluscs (S c h il d e r and Sc h il d e r , 1939), pelagic jellyfish (M a y e r , 1910) and echinoids (M avr, 1954). Among the planktonic crustaceans, the following pairs possibly are also pohiypic species, e.g., euphau­ siids, Thysanoessa inermis and T. neglecta ; hyperiid amphipods, Vibilia australia and its variety pelagica (B e h n in g , 1912) and Parathemisto gracilipes, P. gaiidichaudii, and P. australis (Hurley, 1955). Speciation of the marine animals, as demonstrated by the study of tropical echinoids (M av r, 1954), is not different from that of the terrestrial species. This means that geographical isolation is an important factor in the process of specification. B iizzati-T r a v e r so (1958, in discussion after K o h n ) has suggested that the unidirectional current system, in the absence of other apparent geographical isolation, plays the main role in speciation in the marine environment. From the case of the E. Pacific form and the Indo-W. Pacific form of P. coUetti in the present investigation, it seems more plausible to elucidate the speciation on the basis of M a y r ’s ideas. The E. Pacific form is known from the Hmited material of the Longlining stations in the waters of Central America. The few specimens taken from the southern CCOFl stations also belong tho this form. Since there is no intergrade of this and the Indo-W. Pacific form, and since the E. Pacific form occurs much more often in the Longlining stations than in the CCOFl stations, it is believed that the main distribution area is within the Equatorial Water. Since no collection is available from most of the Pacific, the degree of speciation within this polytypic species is still questionable. The presence of different forms of P. coUetti and P. stebbingi in the E. Pacific and the Atlantic seems to be in agreement with B l r k e n r o a d ’s (1936) observation. He finds that the littoral faunas of the Atlantic and Pacific American coasts are more nearly related to one another than to the faunas of other regions of the world. The reverse seems to be true for the deep-water peneids. He considered that this contrast is due to the shallow depth of the post-Cretaceous intercommunication across Central America between the two oceans. Planktons which possibly also require deeper water to pass from one ocean to the other may therefore have been separated from each other since the Cretaceaous. The case of P. sedentaria is not so clear. Although the males of the E. Pacific and Atlantic have the same short form of antenna 2, there is no evidence to show that individuals of this species are more similar to each other than to those of the Indo-W. Pacific form. Considering the wide range of the geographical distribution, the small number of geographical variations found in this family is striking as compared with those of terrestrial faunas. Bowman (19o3) has attributed the smaller variation among planktons to the following factors: (1) large population size; (2) limited geogra­ phical isolation; (3) relative uniformity and stability of the environment. Although these may be true in general, this present comprehensive study of so-called circumglobal species has revealed that small variations are present, and that they have considerable zoogeographical and evolutionary significance. VI. CONCLUSION AND SUMMARY

1. The present investigation of the family Phronimidae is mainly based on the material collected by the Dana Expeditions 1920-1922 in the Atlantic and the Gulf of Panama, and 1928-1930 around the world. Sup­ plementary materials are obtained from several other collections: the California Cooperative Oceanic Fisheries Investigation (CCOFI) from the eastern Pacific, the Longlining stations from the eastern equatorial Pacific, the Bellairs Research Institute of McGill University from Barbados and the collection deposited at the Zoological Museum of the University of Copenhagen, Denmark. 2. The systematics of this family is revised.-All known species are present except Phronima affinis. Phronima solilaria is restored to specific rank, on morphological and geographical evidence. The possibilities that it may form with either P. sedenlnria or P. ntlanticn a polytypic species or a hybrid form of these two species are discussed. The males of P.pncificn and P.curvipes are distinguished from those of P.colletti and are described. The discovery of the males of these two species strengthens their systematic status. Whether P. affinis is a genuine species is still questionable. Apparent geographical variations are found in three species: in P. sedentaria these are expressed only in the form of the second antennae in the males from the Indo-W. Pacific and from the Atlantic and E. Pacific; three forms are found in both the females and males of P. coUelli: Indo-W. Pacific, Atlantic and E. Pacific; and two in P. stebbingi: Atlantic and E. Pacific. 3. The postnatal development of the phronimids, based on preserved material, is divided into four different periods: juvenile, inmature, adolescent, and mature. Each period is characterized by the degree of devel­ opment of sexual characteristics. They are further subdivided into a number of stages based on the number of podomeres in the pleopod rami and other morphological changes. In the juvenile period, sexual differ­ entiation is not present. The immature period is noted mainly for the growth in size; males and females are distinguished, but the gonad primordia are still rudimentary. The adolescent period is brief and seems to be important for the sexual development. The secondary sexual characters are completely acquired at the moulting between the adolescent and mature periods, particularly obvious in the males. The allo- metric growth of the body and the different patterns of development in the four periods suggests that hormonal control may be present at critical stages of the development. The stages defined by the podomere number in the pleopod rami together with the morphological changes are believed to be related to the moulting processes. 4. The phronimid species are believed to breed for an extended period during the year, and very probably at all times of the year. Evidence suggests that mature females have more than one brood. 5. Judging from the morphology of the mouth-parts and other appendages and from the gut contents, the phronimids are omnivorous in food habit. 6. The vertical distribution of the phronimid species is based on the Dana results, adjusted by calculations. It is shown that at night all but P. sedentaria and P. curvipes occur most abundantly in the depths of 50 and 100 M.\\'. The depths with the highest catch of P. sedentaria are 100 and 300 M.W. The vertical distribution during the day is not known because of inadequate collection methods. The Barbados col­ lections imply that diurnal vertical movement occurs in the members of this family. The actual range of the movement however cannot be determined from these collections. An average of 100-200 metres for the extent of the vertical migration is postulated. This average may be too low judging from the day catch. 7. The geographical distribution considered together with vertical distribution is found to be highly related to the extent of water masses. This agreement is to be expected because the water masses are the basic zoogeographical units of the marine biotope providing its special characteristics, abiotically and biotically. The north and south Subtropical Convergences are the most effective barriers for the distribution of this family. All but Phronima sedentaria and P. atlantica are restricted by these convergences. If the presump­ tion is made that all species descend far enough during the day to enter the water masses underlying the surface water, then it is found that the water masses of the N. and S. Atlantic Central, Eastern N. Pacific Central, Pacific Equatorial, Indian Central and Indian Equatorial waters contain all species, except P. soli- taria which is absent from the Pacific Equatorial water mass. According to available evidence, all species avoid the Eastern N. Pacific Central water mass. Phronima sedentaria, P. atlantica, P. stebbingi and Phro- nimella elongata are present in the Pacific Transitional and Western S. Pacific Central waters. However, Phronima colletti occurs in the former only and P. curvipes is found in the latter only. Both P. sedentaria and P. atlantica invade the Subantarctic water. The single records for P. stebbingi and for Phronimella elongata in this water are considered to be abberant. 8. Judging from present knowledge of distribution and geographical variation, it seems plausible that M a y r ’s (1942) emphasis on geographical isolation as a factor in speciation in the terrestrial environment may also apply to the seas. B lz z .\t i-T r a v er so (1958) has applied somewhat different ideas to account for speciation in marine environment and these ideas have since been accepted by some marine biologists. Whether they will help account for the forms of Phronima colletti cannot be determined until a compre­ hensive study of the Pacific populations is made. The three forms of P. colletti are in some aspects similar to those of Stylocheiron affine discovered by B r i.nto n (1962). Parallel phenomena will probably be found in P. colletti when its distrtibution in the Pacific is completely known. 9. The geographical variations of the phronimid species indicate that among marine planktons, which are often assumed to have few barriers to gene flow and a slow rate of evolution, the process of speciation can always be found by thorough comparison of specimens from different oceanic regions. The widely assumed free communication for circumglobal planktons from the Atlantic to the Indian Oceans by currents south of Africa, is not substantiated by the present investigation. On the contrary, it is suggested that the gene flow between the Atlantic and the Indo-W. Pacific populations is at least in some species prevented by the barrier (or barriers) in this area. The cold Benguela Current may be very effective in preventing the drift of warm-water species from one ocean to the other. BIBLIOGRAPHY

A d a m s , A ., 1850: The zoology of the voyage of H.M.S. B ig e l o w , H. B., 1926: Plankton of the offshore waters Samarang. of the Gulf of Maine. - U.S. Bur. Fish., Bull. 40: 1. A n o n y m o u s, 1951: California Cooperative Sardine Re­ B le g v a d , H., 1922: On the biology of some Danish gam- search Programme. - Progress Repr. 1950. Scarnento, marids and mysids. - Rept. Danish Biol. Stn. No. 28. 54 pp. B o o n e , L., 1930: Scientific results of the cruises of the B a r n a r d , K. H., 1930: Crustacea, Pt. XI. Amphipoda. yachts “Eagle” and “Ara” 1921-28, W illia m K. British Antarctic (Terra Nova) Expedition, 1910. - Vanderbilt commanding. - Crustacea. Bull. Vand. Nat. Hist. Rept. Zool. 8: 307. Mar. Mus. 3: 209. — 1932: Amphipoda. - Discovery Rept. 5:1., B o u s f ie l d , E. L., 1951: Pelagic Amphipoda of the Belle — 1937 a: Amphipoda Hyperiidae. - Australasian Ant­ Isle Strait region. - J. Fish. Res. Bd. Canada 8: 134. arctic Expedition 1911-1914. Sci. Rept. Ser. C (Zool. B ov a lliu s, C., 1887: Systematica list of the Amphipoda & Bot.) II, Pt. 5: 1. Hyperiidea. - K. Svenska Vetenskaps-Akademiens — 1937 b: Amphipoda. - The John Murray Expedition Handlingar 11 (16). 1933-34. Sci. Rept. 4: 130. — 1889: Contributions to a monograph of the Amphi­ — 1940: Contributions to the crustacean fauna of South poda Hyperiidea. - K. Svenska Vetenskaps-Akade- Africa, XII. Further additions to the Tanaidacea, miens Handlingar 22 (7). Isopoda and Amphipoda, together with keys to the B o w m a n , T. E., 1953: The systematics and distribution identification of the hitherto recorded marine and of pelagic amphipods of the Families Vibilidae, Para- freshwater species. - Ann. S. Afr. Mus. 32: 381. phronimidae, Hyperiidae, Dairellidae and Phrosini- B a r r o is , T h . 1888: Catalogue des Crustac^s marins re­ dae from the North Pacific. - Ph. D. Thesis. Univer­ cullies aux Acores etc., p. 50. sity of California at Los Angeles. B a r y , B. M., 1959 a: Species of zooplankton as a means — 1960: The pelagic amphipod genus Paralhemisto (Hy­ of identifying different surface waters and demon­ periidea: Hyperiidae) in the North Pacific and adja­ strating their movements and mixing. - Pac. Sci. cent Arctic Ocean. - Proc. U.S. Nat. Mus. 112: 343. 13: 14. B r in t o n , E., 1962: The distribution of Pacific euphau- — 1959 b: Ecology and distribution of some pelagic siids. - Bull. Scripps Inst. Oceanogr., University of Hyperiidea (Crustacea-Amphipoda) from New Zea­ California, Tech. ser. 8: 51. land Waters. - Pac. Sci. 13: 317. B r u u n , a. F., 1943: The biology of Spirula spirula (L.). B a t e , C. S p e .v c e , 1862: Catalogue of the specimens of Dana Rept. No. 24. Amphipodous Crustacea in the collection of the Bri­ — 1957 a: General introduction to the reports and list tish Museum. - Brit. Mus., London. 4: 1. of deep-sea stations. - Galathea Rept. 1: 7. B e h n in g , a., 1912: Die systematische Zusammensetzung — 1957 b: Deep sea and abyssal depths. Chap. 22 in 1, und geographische Verbreitung der Familie Vibilidae. Treatise on Marine Ecology and Paleoecology (Ed. - Zoologica 26: 211. by J. W. H e d g p e t h ). - Geol. Soc. Mem. 67. B e k l e m is h e v , C. W., 1966: Large-scale pattern of distri­ Bruzelius, R. M., 1859: Bidrag til kannedomen om Skan- bution of oceanic plankton communities. - Second dinaviens Amphipoda Gammaridea. - Kgl. Svenska Intern. Oceanogr. Cong., Abstracts of papers, p. 28. Vet. Handl., Ny Foljd 3: 1. B i e r i , R., 1959: The distribution of the planktonic Chae- B u r k e n r o a d , M. D., 1936: The Aristaeinae, Solenoceri- tognatha in the Pacific and their relationship to the nae and pelagic Penaeinae of the Bingham Oceano­ water masses. - Limnol. Oceanogr. 4: 1. graphic Collection. - Bull. Bingh. Oceanogr. Coil. 5:1. B ig e lo w , H. B., 1915: Exploration of the coast water B u zzati-T r a v e r s o , A. 1958: Discussion in Perspec­ between Nova Scotia and Chesapeake Bay, July and tives in Marine Biology (Ed. by A. A. B l'zzati-T ra- August, 1913, by the U.S. Fisheries Schooner Gam- VERSo), p. 584. - Berkelej' and Los Angeles; Univ. pus. Oceanography and plankton. - Bull. Mus. Comp. Calif. Press. Zool. 59: 149. Ca r u s , j. V., 1885: Prodromus Faunae Mediterraneae. 1. Charniaux-Cotto.n% H., 1960: Sex determination. - The D ana , J. D., 1852: On the classification of the Crustacea physiology of Crustacea (Ed. by T. H. W aterm an) I Choristopoda or Tetradecapoda. - Am. J. Sci. Arts, 1; Chap. 13. Academic Press Inc., New York. ‘ sen 2, 14: 297. Ch ev r eu x , 1\., 1887; Catalogue des Crustaces Amphipo- D is c o v e r y C o m m it t e e , 1929: Station list. - Discovery des marins du Sud-ouest de la bretagne. - Bull. Soc. Kept. 1: 3. " ~ Zool. France 12: 288. D u d l ic h , E., v o n , 1926: Systematische und biologische — 1900: Amphipodes provenant des canipagnes de Studien an den Phronima-Arten des Golfes von I’Hirondelle (1885-1888). - Res. Camp. Scient. 16: 1. Neapel. - Zool. Anz. 6a: 117. — 1913: Sur quelques intoressaiites ospeces d’Amphipo- D u n b a r , M. J., 1957: The determinants of production in des provenant dos jjarages de Monaco et des peches northern seas: A study of the biology of Themisto pelagiques de la Princesse Alice et I’Hirondelle en libellula Mandt. - Can. J. Zool. 35: 797. Medilerranee. - Bull. Inst. Oceanogr. Monaco No. 262 — 1963: The purpose and significance of the Serial — 1935: Amphipodes provenant des Campagnes scienti- Atlas of the .Marine Environment. - In Marine Di­ fiques du Prince Albert I de Monaco. - Res. Camp. stributions (Ed. by M. J. D u .n b a r ). Uni v .Toronto Press. Scient. 90: 1. E b e l i n g , a. W., 1962: Melamphaidae I. Systematics and — and L. F age, 1925: Amphipodes. - Fauna de France zoogeography of the species in the bathypelagic fish No. 9. genus Melamphaes G u n t h e r . - Dana Rept. No. 58. *Chia JE, D el l e . 18J1: Descrizione e notomia degli animali E k m a n , s., 1953: Zoogeography of the sea. S id g w ic k and invertrebrati della Sicilia citeriore, pi. 33, figs. 5-7. J.\cKSON Ltd., London.: 417pp. Chilton, C.. 1911: Scientific results of the New Zealand E v a n s , F., 1961: The planktonic Crustacea of the Petula Government Trawling Expedition, 1907. Crustacea. Transatlantic Expedition. - Proc. Linn. Soc. London - Rec. Canterbury Mus. 1; 285. 1-2: 189. — 1912: .Miscellaneous notes on some New Zealand F a g e , L., 1960: Oxycephalidae. Amphipodes p^lagiques. Crustacea. - Trans. N.Z. Inst. 44: 128. - Dana Rept. 52. — 1921: Some New Zealand Ainphipoda, No. 2. - Trans. F l e m in g , R. H. and T. L a e v a s t u , 1956: The influence N.Z. Inst. 53: 220. of hydrographic conditions on the behaviour of fish. Chu n , C.. 1889 a: Bericht iiber eine nach den Cauarischeu - FAO Fisheries Bull. 9: 181. Inseln im Winter 1887/88 ausgefiihrte Reise. II. Ab- F o r s k a l , p., 1775: Descriptiones Animalium Avium, Am- teilung. Beobachtungen iiber die pelagische Tiefen- phibioruin, Piscium, Insectorum, Vermium, quae in und Oberflachenfauna des ostlichen atlantischen itinere orientali observavit P. F o r s k .4l . - E d . C. Oceans. - Sitzungsberichte der K. Preussischen Aka- N i e b u h r , pp. xxi and 95-96. demie der Wissenschaften zu Berlin, 1889: 519, Gerstaecker, a., 1886: In Dr. H. G. B r o n n ’s Klassen — 1889 b: Das Mannchen von Phronima sedenlaria nebst und Ordnungen des Tliier-Reichs 5, Abth 2, p 487. Bemerkungen iiber die Phronima-Xrten. - Zool. Anz. G i l e s , G. M., 1887: On six new amphipods from the Bay 12: 378. of Bengal. - J. Asiatic Soc. Bengal, 56: 212. — 1895: Atlantis. Biologische Studien iiber pelagische G o o d b o d y , j. 1965: Continuous breeding in populations Organismen IV. Die sekundiiren Geschlechtscharak- of two tropical crustaceans, M ysidium columbiae tere der Mannchen von Phronima. - Bibliuth. Zool. (Zim m e r ) and Emerila portoricensis S c h m id t . - Ecol. 19: 109. 46: 195. — 1896: Die sekundaren Geschlechtscharaktere der G o r d o n , G ., 1881: Phronima sedenlaria and its beroe. - Miinnchen von Phronima. - Biblioth. Zool. 7. Scot. Nat. 6: 56. Claus, C.. 1862: Bemerkungen iiber Phronima sedenlaria G r i c e , G. D. and A. D. H a r t , 1962: The abundance, F orsk., und elongata, n. sp. Zeitsciier. - Wissensch. seasonal occurrence and distribution of the epizoo- Zool. 12: 189. plankton between New York and Bermuda. - Ecol. — 1871: Untersuchungen iiber den Bau und die Ver- Monogr. 32: 287.

wandtschaft der Hyperiden. - Nach. k. Gesellsch. G u e r i n , F. E., 1836 a.: Description de quelques genres Wiss. Georg-Augusts-Univ. Gottingen, p. 1J9. nouveaux des Crustaces appartenant a la famille des — 1872 a. Zur Naturgeschichte der P/iromVna scrffn/an'a, Hyperines. - Mag. Zool. 6 Annee, Classe 7, p. 7, pi. F o r s k . Zeitscher. - Wissensch. Zool. 22 : 331. 18, fig. 1.

— 1872 b: Grundziige der Zoologie. - 2. Aufl., p. 467. — 1836 b: Icongraphie du Regne Animal de G. C u v i e r , — 1879: Organismus der Phronimiden. - Arb. Zool. Crustaces. P. 21.

Inst. Univ. Wien 2: 59. H a f f n e r , R. E., 1952: Zoogeography of the bathypelagic *Cocco, A., 1832: Su di alcuni nuovi crustacei de mari fish, Ch a u l io d u s . - Syst. Zool. 1: 113. di Messina. - Effemeridi scientifiche e letterararie per H a l e , H . M., 1929: The Crustacea of S. Australia. Pt. 2. la Sicilia. 2: 208. - Government printer, Adelaide. *CosTA, A., 1853: Fauna del Regno di Napoli, p. 1. H a r d y , A. C. and E. R. G u n t h e r , 1935: Plankton of the South Georgia whaling grounds and adjacent waters, * Original paper not seen by the author. 1926-1927. - Discovery Rept. 11: 1. Holmes, S. J., 1905: The Amphipods of Southern New Latreille, P. A., 1802: Histoire naturelle, g^n^rale et England. - Bull. Bur. Fish., Washington, 24: 465. particuliere des Crustac6s et des Insectes. 3. — 1909: The Amphipoda collected by the U.S. Bureau — 1803: Histoire naturelle, gen6rale et particuliere, des of Fisheries Steamer “Albatross” off the west coast Crustaces et des Insectes. 6. of North America, in 1903 and 1904, with descrip­ — 1806: Genera Crustaceorum et Insectorum. 1. tions of a new family and several new genera and spe­ — 1829: Le Regne Animal par C u v ie r . Nouvelle 6d. cies. - Proc. U.S. Nat. Mus. 35: 489. 4me. H urley, D. E., 1955: Pelagic Amphipods of the Sub­ L ea c h , W. E., 1813: “Crustaceology”. The Edinburgh order Hyperiidea in New Zealand Waters. I. Systema- Encyclopaedia. 7: 403. tics. - Trans, roy. See. New Zealand, 83: 119. — 1813-1814: Article Crustaceology, Appendix. The — 1956: Bathypelagic and other Hyperiidea from Cali­ Edinburgh Encyclopaedia. 7: 429. fornia waters. - Allan Hancock Foundation Publ., — 1815: A tabular view of the external characters of Occ. Pap. 18. four classes of animals, which Linne arranged under — 1960 a: Pelagic Amphipoda of the N.Z.O.I. Pacific Insecta. - Trans. Linn. Soc. London, 11: 355. cruise, March 1958. - New Zealand J. Sci. 3: L e g e n d r e , R., 1940: La Fauna p61agique de I’Atlantique 274. au large du Golfe de Gascogne recueillie dans des — 1960 b.: Amphipoda Hyperiidea. B.A.N.Z. Antarctic estomacs de Garmons. Troisieme partie: Invertebr^s Research Expedition 1929-31. - B.A.N.Z. Antarctic (Cephalopodes exclus). Parasites du Germon. - Ann. Research Expedition Rept., Ser. B, 8: 107. Inst. Oceanogr. Monaco, N.S. 20: 127. H uxley, J. S., 1942: Evolution, the modern synthesis. L e g r a n d , j. j. and A. V a n d e l , 1948: Developpment Allen and Unwin, London. post-embryonnaire de la gonade chez les Isopodes — 1955: Morphism and evolution. Heredity 9: 1. terrestres normaux et intersexues. - Bu. Biol. France Irie, K., 1958: Some species occurred in Tsushima Cur­ et. Bilg. 82: 79. rent and its neighbouring waters, and their biology. L e w is , J. B., J. K. B r u n d r it t and A. G. F is h , 1962: - The reports of Explorative Investigations on The biology of the flyingfish Hirundichthys affinis Tsushima Current and its neighbouring waters. (G u n t h e r ). - Bull. Mar. Sci. G ulf Carib. 12: 73. 2: 138. Ling, Shao-wen, 1941: Notes on a Phronima from Hong­ — 1959: Studies on pelagic amphipods in the adjacent kong. - Hongkong Nat. 10: 190. seas of Japan. - Bull. Fac. Fish. Nagasaki Univ. Lo B ia n c o , S., 1903: Le pesche abissali esenguite da 8: 20. F. A. Kruph col Yacht Puritan nelle adiacenze di J espersen, p ., 1935: Quantitative investigations on the Capri ed in altre localita de Mediterraneo. - Mitt. distribution of macroplankton in different oceanic Zool. Stat. Neapel 16: 109. regions. - Dana Rept. No. 7. — 1909: Notizie biologiche riguardanti specialniente il — and A. V. TAning, 1934: Introduction to the reports periodo di maturita sessuale degli animali del golfo from the Carlsberg Foundation’s Oceanographical di Napoli. - Mitt. Zool. Stat. Neapel, 19: 513. Expedition Round the World 1928-30. - Dana Rept. L o c h h e a d , j. H., 1963: Discussion in Phylogeny and No. 1. Evolution of Crustacea (Ed. by H. B. W h it t in g t o n J ohnson, M. W. and E. Brinton, 1963: Biological spe­ andW. D. J. R o l f e ), p . 22. Spec. Publ.-Mus. Comp. cies, w'ater-masses and currents. - Chap. 18 in 2, Zool., Cambridge. The Sea (Ed. by M. N. H ill). Intersciences Publish­ L u cas, H., 1940: Historic Naturelle des Crustaces, des ers, New York and London. Arachnides et des Myriapodes. Paris. J ohnston, T. H., 1937: Biological organization and sta­ M a c d o n a l d , J. D., 1874: On the anatomy and habits of tion list. - B.A.N.Z. Antarctic Expedition 1929-1931, the genus Phronima (Latr.). - Proc. roy. Soc. London Repts. Ser. B (Zool. & Bot.) 1:1. 22: 154. Joubin, L. and L. R oule, 1918: Observations sur la nou- M a y e r , A. G., 1910: Medusae of the World. III. The riture des Thous de I’Atlantique {Germo alalonga Scyphomedusae. - Carnegie Inst. Washington, Publ. Gmelin). - Bull. Inst. Oceanogr. Monaco, No. 348. No. 109: 499. K ane, J. E., 1962: Amphipoda from waters south of New M a y r , E., 1942: Systematics and the origin of species. - Zealand. - New Zealand J. Sci. 5: 295. Columbia Univ. Press, New York. — 1963 a.: Stages in early development of Parathemisto — 1954: Geographic speciation in tropical echinoids.- gaudichaudii (Guer.) (Crustacea Amphipoda: Hyper­ Evol. 8: 1. iidea), the development of secondary sexal characters — 1963: Animal species and evolution. - Belknap Press and of the ovary. - Trans, roy. Soc. New Zealand of Harvard Univ. Press, Cambridge. Mass. Zool.) 3: 35. M c G o w an , J. A., 1963: Geographical variation in Lima- — 1963 b .: Observation on the moulting and feeding of cina helicina in the North Pacific. - Syst. Assn. Publ. a hyperid amphipoda. - Crustaceana 6: 129. 5: 109. L amarck, J. B. P. A., 1818: Histoire naturelle des Ani- M cH u g h , J. L., 1952: The food of albacore (Germo ala- maux, sans vertebres. o: 179. lunga) off California and Baja California. - Bull. Scripps Inst. Oceanogr., Univ. of Calif., Techn.ser. Sc h m id t, JoHS., 1912: Introduction.-Rept.Danish Ocean­ 6: 161. ogr. Exped. 1908-1910 to the Mediterranean and .Mil n e -E d w a r d s, H., 1838: Hibt< ire naturelle des Ani- adjacent seas. 1: 1. niaux sans vert^br^s - par J. B. P. A. L a m a r k . 2 ed. — 1929: Introduction to the oceanographical reports, 5, p. 303. including list of the stations and hydrographical ob- — 1840: Histoire naturelle des Crustac^s. 3, p. 93. servartions. - Rept. Danish “Dana” Exped. 1920-22 M in k ie w ic z , R., 1910: Menioire sur la biologic du Tonne- in North Atlantic and Gulf of Panama. 1: 1. lier de mer (Phronima sedentaria). - Bull. Inst.0c6an- ScHMiDTLEiN, R., 1879: Beobachtungen iiber Trachtig- ogr. Monaco, Nos. 146 & 152. keits- und Eiablage-Penoden verschiedener Seethiere, M o c k , H., 1926; 1927 a.: Versuch einer Formanalyse bei Januar 1875-Juli 1878. - Mitt. Zool. Stat. Neapel, 1: Hyperiden. - Rev. Hydrobiol. Hydrogr. 14: 160 & 124. 276; 17: 1. ♦SCHOUSBOE, P. K. A., 1802: “ lakttagelser over tvende — 1927 b.: Die Phronimiden der Deutschen Siidpolar- sieldne og lidt bekeindte Krebsarter” . - Skrivter af Expedition 1901-1903. - Deutsche Siidpolar-Expe- Naturhistorie Selskabet. 5,2: 11. dition 1901-1903, 19; 123. S e g e r s t r .^l e , S. G., 1950: The amphipods on the coasts M o o r e , H. B., 1949: The zooplankton of the upper waters of Finland. - Some facts and problems. - Soc. Sci. of the Bermuda area of Noth Atlantic. - Bull. Bing­ Fenn. Comm. Biol. X (14). ham Oceanogr. Coll. 12: 1. S ex to .n , E. W., 1924: The moulting and growth stage of N o r m a n , A. M., 1900: British Amphipoda of the Tribe Gammariis, with description of the normal and inter­ Hyperiidea. - Ann. -Mag. Nat. Hist. Ser. 7 5: 106. sexes of G. f/ieyreux;. - J. Mar. Biol. Ass.U. K. 13: 340. Pagenstecher, H. a.. 1861: Cber Phronima sedentaria — and A. M a t th e w s . 1913: Notes on the life history Forsk. - Arch. Naturgesch. 27 Jahrg. 1: 15. of Gammarus chevreuxi. - J. Mar. Biol. Ass. U. K. 9: P e .\.r s e . a. s., 1913: Notes on certain amphipoda from 546. the Gulf of Mexico, with description of new genera S h ih , C. and M. J. D u n b a r , 1963: Amphipoda. Suborder: and new species. - Proc. U.S. Nat. Mus. 43: 369. Hyperiidea. Family: Phronimidae. - Cons. Perm. P e s t a , O., 1920: Cber einige fiir die Fauna der Adria Fisches d’ldent. Zooplankton, Sheet 104. neue Oder seltene Amphipodenarten. Zool. Anz. Shoemaker, C. R., 1945: The Amphipoda of the Bermuda 51: 25. Oceanographic Expeditions, 1929-1931. - Zoologica. PiCKFORD, G. E., 1946: Yampyroteuthis infernalis Chun. N. Y., 30: 185. An archaic dibranchiate cephalopod. 1. Natural hi­ SiEBOLD, K. VON and H. St a n n iu s . 1854: Comparative story and distribution. - Dana Report No. 29. anatomy. 1. (tr. by W. I. B u r n e t t ). G o u ld & L in ­ PiRLOT, J. M.. 1929: Les Amphipodes Hyperides. R6sul- c o l n , Boston. tats Zoologiques de la Croisiere de r “AR.MAUER S ie g f r ie d , W. R., 1963: The Hyperiidea (Amphipoda) H ansen” (1922). Fasc. 1. - Mem. Soc. Roy. Sci. off the west coat of southern Africa. - Div. Sea Fish. Liege, 3e serie, 15: 1. Invest. Rept. 48. — 1930: Les .\niphipodes de I’Expedition du Siboga. L Sp a n d l , H.,1924 a.: Expeditionen S. M. Schiff “Pola” in Les Amphipodes Hyperides. - M ax W e b e r , Siboga- das Rote Meer, nordliche und sudliche Halfte. 1895/ Expeditle X X X H I a. 96-1897/98. Zoologische Ergebnisse XXXV. Die Am- — 1932: Introduction a I’Etude des Amphipodes hype­ phipoden des Roten Meeres. - Denks. Kaisevl. Akad. rides. - Ann. Inst. Oceanogr. Monaco, N.S. 12: 1. Wissens. (Math., Natur. & Classe), No. 99. P o w e l l . W. B., 1947: Native animals of New Zealand. — 1924 b.: Amphipoden Hyperiidea aus der Adria.- Auckland. Zool. Anz. 58: 261. P o w e l l , L., 1875: Description of a new crustacean S p o o n e r , G. M., 1947: The distribution of Gammarus Phronima novae-zealandiae. - Trans. Proc. New Zea­ species in estuarines. Part I. - J. Mar. Biol. Ass. U. K. land Inst. 7: 294. 27: 1. R a y m o n t , j. E. G., 1963: Plankton and productivity in Sp r in g e r , S. and H. R. B u l l is , Jr., 1956: Collections by the oceans. - ]SIacmillan Co., New York. the “Oregon” in the Gulf of Mexico. - U.S. Dept. R e i d , D. M., 1955: Amphipoda (Hyperiidea) of the coast Int. Spec. Sci. Rept. Fish. No. 196. of tropical West Africa. - Atlantide Rept. 3: 7. St a n l e y , J., 1962: The discriminant function (mimeo­ ♦R isso, A., 1816: Histoire naturelle des Crustaces des graphed). environs de Nice. P. 120. St e b b i.n g , T. R. R., 1888: Report on the Amphipoda col­ Sa r s , G. O., 1895: An account of the Crustacea of Nor­ lected by H.M.S. Challenger during the years 1873­ way. 1876. - “Challenger” Rept., Zool. 29. S chellenberg , a., 1927: Amphipoda des nordischen — 1904: Biscayan plankton: Part II. The Amphipoda Plankton. - In Nordisches Plankton, 3. and Cladocera. - Trans. Linn. Soc. London. Ser. 1, ScHiLDER, F. A. and M. S c h il d e r , 1939: Prodrome of a 10: 13. monograph on living Cypraeidae. - Proc. Malac. Soc. S t e b b in g , T. R. R., 1910: General catalogue of S. African London, 23: 119. Crustacea. Part V. - Ann. S. Afr. Mus. 6: 281. St e in b e r g , J. E. and E. G. D o u g h e r t y , 1957: The ske- from the North Pacific coast. - Univ. Wash. (State) ^ leton shrimps (Crustacea; Carpellidae) of the Gulf of Publ. Oceanogr. 4: 50. Mexico. - Tulene Stud. Zool. 5: 267. University of California, Scripps Institution of Oceano­ St e p h e n s e s , K., 1923; Crustacea Malacostraca V. (Am- graphy. 1949 a. Physical and chemical data. Cruise 1. phipoda I). - The Danish Ingolf-Expedition 3 (8). Marine Life Research Programme 28 February-16 — 1924; Hyperiidea-Amphipoda. Pt. 2 -Danish Oceano­ March 1949. (Mimeographed). graphical Expeditions 1908-10. II. D. 4. — 1949 b.; Physical and chemical data. Cruise 5. Marine St e u e r , a., 1911: Adriatische Planktonamphipoden, - Life Research Programme. 1-16 July 1949. (Mimeo­ Sitzungsber. K. Akad. Wiss., Wien, Math. Natur- graphed). wiss. Kl., 120: 671. — 1950. Physical and chemical data. Cruise 9. Marine — 1912: Einige Ergebnisse der VII. Terminfahrt S.M.S. Life Research Programms. 8-25 November 1949. Najade in Sommer 1912 in der Adria. - Intern. Rev. (Mimeographed). Hydrobiol. Hydrogr. 5: 551. — 1951: Physical and chemical data. Cruise 20. Marine St e w a r t , D. A., 1913: A report on the extra-Antarctic Life Research Programme. 9-28 November 1950. amphipod Hyperiidea collected by the Discovery. (Mimeographed). - Ann. Mag. Nat. Hist. Ser. 8, 12: 254. Vinogfadov, M. E., 1962: Hyperiids collected by the St r e e t s , T., 1877: Contributions to the natural history Soviet Antarctic Expedition with the R.V. “Ob” of the Hawaiian and Fanning Island and Lower Cali­ southward from 40° S. - Explorations of the fauna fornia. - Bull. U.S. Nat. Mus. 1877, No. 7, p. 128. of the seas 1, 9:5. — 1882: A study of the Phronimidae of the North Paci­ VossELER, J., 1901: Die Amphipoden der Plankton-Ex- fic surveying expedition. - Proc. U.S. Nat. Mus. 5; 3. pedition. - Ergebnisse der Plankton-Expedition der Sv e r d r u p , H. U., M. W. J o h n so n and R. H. F l e m in g , Humboldt-Stiftung, 2 G.e. 1942: The oceans, their physics, chemistry, and ge­ W a l k e r , A. O., 1903: Report on the Isopoda and Amphi­ neral biology. Prentice-Hall, Inc., New York. poda collected by Mr. G e o r g e M u r r a y , F.R.S., T a t t e r sa l l , W. M., 1906: The marine fauna of the coast during the cruise of the “Oceana” in November 1898. of Ireland. Part VIII, Pelagic Amphipoda of the - Ann. Mag. Nat. Hist. Ser. 7 12: 223. Irish Atlantic Slope. - Fish. Ireland, Sci. Invest. 4: 1. — 1909; Amphipoda Hyperiidea of the “Sealark” Ex­ T e is s ie r , G., 1960: Relative growth. Chap. 16 in vol. 1, pedition to the Indian Ocean. - Trans. Linn. Soc. The physiology of Crustacea (Ed. by T. H. W a t e r ­ London, Ser. 2, Zool. 13: 49. m an ). - Academic Press Inc., New York. W il s o n , R. C. and B. M. S h im a d a , 1955: The longlining: T h o m s e n , H., 1931: Nitrate and phosphate contents of results of a cruise to the eastern tropical Pacific Mediterranean water. - Rept. Danish Oceanogr. Ex- Ocean. - Calif. Fish & Game. 41: 91. ped. 1908-10. 3 (6). W h it e , A., 1847: List of the specimens of Crustacea in — 1937: Hydrographical observations made during the the collection of the British Museum. “ Dana” Expedition 1928-30. - Dana Report No. 12. — 1850: List of the sepcimens of British animals in the T h o m s o n , G. and E. C h il t o n , 1886: Critical list of the collection of the British Mseum. Part IV. Crustacea. Crustacea Malacostraca of New Zealand. Part I. - W y r t k i, K., 1966: Oceanography of the eastern Equato­ Trans. Proc. New Zealand Inst. 18: 141. rial Pacific Ocean. - Oceanogr. Mar. Biol. Ann. Rev. T h o r e , s., 1949: Investigations on the “ Dana” Octopo- 4: 33. da. I. Bolitaenidae, Amphitreitidae, Vitreledonellidae Y a n g , W. T., 1960: A study of the subgenus Parahyperia and Alloposidae. - Dana Rept. No. 33. (Genus Hyperia; Amphipoda; Hyperiidae). - Bull. T horsteinson , D., 1941: New or noteworthy amphipods Mar. Sci. Gulf Carib. 10; 11. Appendix Table 1

The discrimination of the male forms of Phroninm pacifica, P. collelti and P. ciirvipes.

The calculation of the discriminant function between each pair of these three species follows the metod described by S t a n l e y (1962), a modification of the method discussed in C. H. G o u l d e n ’s (1952) Methods of Statistical Analysis (pp. 378fF.). The raw data for the discriminant function of each pair are tabulated. Procedures of calculation are omitted. The result of F-test is shown in the table.

A. pacifica vs. ciinnpes. The characters selected for the discriminant function are the length ratio of 1) peraeon to pi eon, 2) head to peraeon segment 1-3 and 3) peraeon segments 1-3 to 4-6.

The raw data. Each sample contains 1 0 mature individuals w, = 6.6929, Wj = - 0.0337, taken from Dana station 3998 W3 = 1.9852.

pacifica curvipes Zpac = 8.4622; Zgur = 9.1207.

1 2 1 2 3 3 D = w,d, + Wjdj J- Wjdj = 0.6586

1.13 0.93 0.73 1.23 1 . 1 1 0.61

1 . 1 1 0.97 0.70 1.19 1.15 0.58 N p acN cu ^ ^ ,^ 2.1688. ^pac 1.07 1 . 0 0 0 . 6 8 1.23 1 . 1 0 0.60 1.05 1.04 0.72 1.24 1.19 0.54

1 . 1 2 1.08 0.62 1.18 1.23 0.52 The analysis of variance

1.05 1.04 0.63 1 . 2 2 1.15 0.59 Sum of ^ j Variance 1.06 1 . 0 0 0.67 1.17 1.59 0.49 squares estimate 1.06 1 . 0 0 0.63 1.15 1.45 0.63

1 . 0 2 1.04 0.63 1.24 0.53 Between species...... 2.1688 3 0.7229 1.18 ------17.55** 1.04 1 . 0 0 0 . 6 8 1.23 1.19 0.54 Within species...... 0.6586 16 0.0412 means Entering an F Table, an F value of 17.55 with such d.f. could have 1.071 1 . 0 1 0 0.669 1 . 2 0 2 1.240 0.563 arisen by chance is less than 1

B. pacifica vs. coUetti. The characters selected for the discriminant function are the length ratio of 1) head to peraeon segments 1-3, 2) peraeon segments 1-3 to 4-6 and 3) peraeon segment 7 to 4-6.

The raw data. Each sample contains 10 mature individuals Wi = 0.0001, w^ = -0.7226, taken from Dana stations 3998 {pacifica) and 4000 (collelti). w = 4 9048

pacifica collelti Zpae = 4.0193; = 3.5177.

1 2 3 1 2 3 D = w’ld, ^ Wjdj + Wjd, = 0.5016

0.93 0.73 0.95 1 . 2 2 0.64 0 . 8 6 0.97 0.70 0.93 1.23 0.60 0.84 = 1.2580 Npac + i'‘col 1 . 0 0 0 . 6 8 0.95 1.38 0.56 0.81 1.04 0.72 0.97 1.38 0.57 0.83 1.08 0.62 0.85 1.23 0.55 0.81 The analysis of variance

1.04 0.63 0 . 8 8 1.39 0.51 0.78 Sum of , Variance 1 . 0 0 0.67 0.95 1.19 0.59 0.78 d.f. squares estimate 1 . 0 0 0.63 0.90 1.36 0.57 0.80 Between species...... 1.2580 3 0.4193 1.04 0.63 0.90 1 . 1 1 0.56 0.74 ______13 35** 1 . 0 0 0 . 6 8 0.95 1.19 0.54 0.76 Within species...... 0.5016 16 0.0314 ' means Entering an F Table, it is found that F 13.35 with such d.f. could have 1 . 0 1 0 0.669 0.923 1.268 0.569 0.801 arisen by chance is less than 1 “/„. C. colletti vs. ciirvipes. The characters selected for the discriminant function are the length ratio of 1) peraeon to pleon, 2) peraeon segment 7 to pleon segment 1 and 3) width to length of carpus 5.

The raw data. Each sample contains 10 mature individuals Wj = 10.1579, Wj = - 1.3341, taken from Dana stations 4000 (colletti) and 3998 (curuipes). W3 = 10.1461. colletti curvipes = 2.0127; = 2.4534. 2 3 1 2 3 D = \v,d, ^ Wjdj - Wjdj = 4.4066

1 . 1 2 1.06 1 . 0 0 1.23 1 . 2 1 1.40 1.13 1.09 0.97 1.19 1.18 1.28 . 97.0906. ^col ^ ^cur 1.09 1.06 1 . 0 0 1.23 1.09 1.39 1.09 1.06 0.97 1.24 1.14 1.31 1.13 1.09 1.03 1.18 1.09 K48 The analysis of variance

1 . 1 2 1.06 1.03 1 . 2 2 1.09 1.33 Sum of ^ j Variance 1.16 1.06 1 . 0 0 1.17 1.15 1.38 squares ' ' estimate 1.07 1 . 0 0 1.03 1.15 1.09 1.42

1.15 1 . 0 0 0.97 1.18 1.14 1.27 Between species...... 97.0906 3 32.3635 ------117.51** 1.15 1.06 1 . 0 0 1.23 1.18 1.38 Within species ...... 4.4066 16 0.2754 means Entering an F Table, an F value of 117.51 with such d.f. could have 1 . 1 2 1 1.054 1 . 0 0 0 1 . 2 0 2 1.136 1.364 arisen by chance is almost vanishingly small.

Appendix Table 2 An illustration to show the estimation of catch per haul in one S 200 hour at various depths by non-closing nets (after B r u u .v , 1943 and T h o r e , 1949 Avith modification).

Estimated time (in hr) consumed M. \V. Total catch Actual catch at the assumed range of depth

0 ...... 0 0 1,60 50...... 2 0 2 0 1,30 1 0 0 ...... 80 79.3 1 , 1 2 300...... 70 62.7 1 , 6 600...... 2 0 2 . 2 7,30 1 0 0 0 ...... 5 +

All the hauls of the above example are assumed to have been taken by S 200 net and to have been towed horizontally at the desired depth for one hour. The speed of the lowering and pulling in the hauls is placed at 1000 M.\V./20 inin. The actual catch per S 200 hour at a certain depth is assumed to represent the popu­ lation density of the water layer extended from this depth halfway to the depth of the hauls above and below it. The time consumed at this range of depth (column 3 of the table) is estimated. By subtracting the catch from the water layer (or layers) above the desired depth of the haul from the total catch, the actual catch is obatined. For instance:

M.W. 100: 80-20 X - = 79.3; oO

1 1 i M.W. 300: 70- 20 X - + 79.3 X -„ = 62.7; etc. oO 1 ^ ^

“ + ” means that the total catch in the haul probably is taken from the water above the desired depth.

Dana-Report No. 74,1969 11 Appendix Table 3

Phronimid specimens examined by the present study.

A. Dana Expeditions 1921-22 (For data on hauls cf. Schmidt 1929). (Selected samples mostly from deep hauls).

seder solit. pac.ifica colletti cun’ipes steblyingi elongata Station M.W. taria atla ntica f m t m f t m f 1 m f m f in f m

Atlantic

1108 (4)...... 50 1

1123 (■«)...... 50 1 1 1 - (S)...... 25 1 t

1145 (2 )...... 400

1152 (1 )...... 7000 1

1157 ( 1 )...... 1 0 0 0 1 - (5)...... 5000 2

(1 0 ) ...... 1 0 0 0 3

1159 (1 ) ...... 5000 5 5 !• . .

(5)...... 1 0 0 0 1

1160 (2 ) ...... 1 0 0 0 3

1163 (2 ) ...... 1 0 0 0 1 (3)...... flOO 5 80 )• . .

2 1165 (2 )...... 1 0 0 0

1166 (2 ) ...... 1 0 0 0 3

1168 (2 )...... 1 0 0 0

1170 ( 1 ) ...... 1 0 0 0 1

1178 ( 1 )...... 1 0 0 0 1 1185 n i ) ...... 6000 1

1188 (2 )...... 1 0 0 0 2 - (5)...... 1 0 0 1

Caritibean Sea

1190 (9)...... 50 1

1192 (5)...... 600 1 1

- (6 ; ...... 300 4 1 1 8 1

- (7)...... 1 0 0 48 4 4 1 2 1 1

- (8 )...... 50 6 2 4 1 1 1

Gulf of Panama

1206 (1 )...... 4500 1

- (7)...... 1 2 0 0 8

1208 (4)...... 3500 1 - (13)...... 3600 1

1209 (1 )...... 3500 2 2

Caribbean Sea Are a

1214 (1) 1 0 0 0 1

1215 1 1 )...... 1 0 0 0 1 1 - (5)...... 600 2

1216 (1 )...... 1 0 0 0 2 (6 )...... 1 0 0 0

1223 ( 1 )...... 1 0 0 0 1

1225 (1 )...... 1 0 0 0 1

1228 ( 1 )...... 1 0 0 0 1

1231 ( 1 ) ...... 1 0 0 0 2

1238 ( 1 ) ...... 800 1 - (3)...... 400 1 1250 (■«)...... 1 0 0 1

Sexually indelermined juveniles. sedentaria atlantica solit. elongata station MAV. pacifica colletti curvipes stebbingi t m t m t f m f m f m f m f

1283 (1). 1 0 0 0 1 - (7). 4000 2 1 1286 (1 ). 1 0 0 0 1

1294 (3). 600 1 1 - (4). 300 1 5

Atlantic

1322 (1). 1 0 0 0 1

- (5). 1 0 0 1 - (6). 900 1 1325 (1). 900 1 1326 (1). 1 1 0 0 1 , ■■ 1327 (6 ). 900 1

1330 (2). 700 1

1332 (7). 700 2

1334 (1). 1 0 0 0 1

1336 (1). 1 0 0 0 1

1339 (1). 1 0 0 0 3

1341 (1). 1 0 0 0 1

1342 (1). 4500 1 - (6). 1 0 0 0 1 1345 (1). 1 0 0 0 39

1349 (1). 1 0 0 0 1

1356 (1). 1 0 0 0 1

1358 (1), 7000 1

1361 (1). 1 0 0 0

1362 (1). 1 0 0 0

- (4). 2 0 0 1

1365 (1). 1 0 0 0 1 - (9). 5000 6 1366 (1). 1 0 0 0 13 - (7). 50 .. 1367 (1). 1 0 0 0 1

1368 (1). 1 0 0 0 4 - (6). 1 0 0 1369 (1). 1 0 0 0 6

1370 (1). 1 0 0 0 2 1

1371 (1). 1 0 0 0 2 0

1372 (1). 1 0 0 0 2

1374 (1), 1 0 0 0 14 2

1 2 0 * - (8)- 1 0 0 0 97 1 52 196*

1377 (1). 1 0 0 0 16 1 . . 103* - (8). 1 0 0 0 38 1 .. 2 0 *

1379 (1). 1 0 0 0 13 1 1

8 6 *

1380 (1). 1 0 0 0 6 1 .. 1 B. Dana Expedition 1928-30 (For data on hauls cf. Jespersen & Taning 1943).

sedenlaria allantica solit. paciftca cottetti carotpes stebbingi elongata f m f I m I f m f m f m f t

South Paciftc-Indo Malaya (Selected samples mostly from deep hauls) 3548 (1) ...... 4000 2 3550 ( 1) ...... 1000 1 3561 ( 1) ...... 5000 4 3577 (1).... 1000 2 3579 ( 1) ...... 1000 1 3580 ( 1) ...... 1000 1 3591 ( 1) ...... 1000 1 3562 ( 1) ...... 1000 1 3621 ( 1) ...... 5000 1 3624 (1).... 5000 1 (6) ...... 1000 2 362 6 ( 1) ...... 1000 1 (7)...... 2000 11 3627 (6) ...... 1000 2 3629 ( 1) ...... 1000 7 3630 (4)...... 1000 1 3631 (1) ...... 1500 5 3640 (6) ...... 3000 4 3642 (6)...... 1 0 0 0 14 3644 (1)...... 1000 10 3653 (1)...... 1 0 0 0 3663 (6)...... 1 0 0 0 1 3676 (1)...... 1 0 0 0 2 3678 (6)...... 1 0 0 0 3 1 »

3680 (6 ). 1 0 0 0 1

3682 (1). 1 0 0 0 8

3683 (6 ). 1000 1

3684 (6 ). 3000 1 3685 . 50-0 - (!)• 1000 2 - (6). 5000 2 1 - (10). 1000 18 11

3686 (6K 4000 5 1 {-)■ 3500 1 1 (8). 3000 7 1 3

(9). 2000 2 6 (10). 1000 42 20 14 12*

Indo-Malaya-Indian Ocean (Complete material) 3687 (1). 1000 2 - (4). 1 0 0 2 - (5). 50 3688 (1). 4000 1

- (2 ). 3500 1 3 - (3). 3000 4 2 - (4). 2000 2 4 10 - (5). 1000 6 6 3 3689 (1). 3000 1

- (2 ). 2500 4 1 1 - (3). 2000 2 2 4

- (4). 1500 3 2 5

- (5). 1000 4 3 2

- (7). 600 6 2 2 3689 (8 ). 300 29 39 10 - (9). 1 0 0 3 3 seden iaria alia ilica solit. pacipca colletli curvipts Station M.W. stehhnngi elonguta f m 1 m 1 r m m I 1 m t ni 1 ni ' 1 f

3689 (1 0 ) ...... 50 1 1 1 2

- ( 1 1 ) ...... 1500 1 1

3690 (2 ) ...... 600 2 1 1 1 1 1

- (3)...... 300 16 8 6 3 2 4 4 1 9 1 1

- (4)...... 1 0 0 1 3 4 2 1 - (5)...... 50 1 1 4

3712 (2 ) ...... 600 1 1 1 1 1 1 9 1

- (3)...... 300 1 0 13 2 2 5 1 1 6 - (4)...... 100 3 1 6 3 4 1 105 32 - (5)...... 50 1 4 9 10 7 7

3713 (2 )...... 600 2 4 1 - (3)...... 300 10 5 .. 1 - (4)...... 100 9 2 3 4 1 2 •1 1 - (5)...... 50 16 4 7 8 5 2 2

3714 (2 ) ...... 600 2 6 3 - (3)...... 300 8 17 9 1 - (4)...... 1 0 0 42 18 6 1 6 5

- (6 ) ...... 6000 2

3715 ( 1 ) ...... 1 0 0 0 1

- (2 )...... 600 5 1 1 1 - (3)...... 300 13 9 7 • 1 2 3 1 - (4)...... 1 0 0 46 34 28 18 2 2 4 3 51 14 - (5)...... 50 5 4 9 5 2 4

3716 (1 )...... 4000 4

- (2 ) ...... 3000 4

3718 (2 )...... 600

- (3)...... 300 1 - (4)...... 1 0 0 4 1 2 - (5 )...... 50

3720 (1 ) ...... 300 1 3

3722 (1 ) ...... 1 0 0 0 3 1I*

3723 (1 ) ...... 1 0 0 0 1

3727 (1 ) ...... 300 5

3728 (1 )...... 1 0 0 0 1

3729 (1 ) ...... 1 0 0 0 3

3730 (1 ) ...... 1 0 0 0 2

3731 (2 ) ...... 600 2 3 2 - (3)...... 300 15 1 1 3 1 - (4)...... 1 0 0 150 33 14 17 - (6)...... 1 0 0 0 1 - (7)...... 600 4 - ( 1 1 ) ...... 3000 1 - ( 1 2 ) ...... 2500 5 2 3734 ( 1 ) ...... 1 0 0 0 2 3736 ( 1 ) ...... 2500 1 - ( 2 ) ...... 2 0 0 0 5

- (3)...... 1500 1

- (6 ) ...... 600 32 5 1 1 1 - (") ...... 300 64 64 7 9 4 5 - (8 )...... 1 0 0 8 1 2

- ( 9 ) ...... 50 1

3738 (1 ) ...... 1 0 0 0 1

3739 (1 ) ...... 1 0 0 0 2

- (2 ) ...... 600 2 0 8 6 1 - (4)...... 100 1 - (5 )...... 50 4 - (6)...... 5 0 0 0 2 - ( 9 ) ...... 2000 1 1 3740 ( 1 ) ...... 1000 2 se/tenlaria allaittica solil. pacifica collelli curv ipes slebtlingi elongata Station M.W. f m f m f f m f m f m f m f 1 m

3744 ( 1 ) ...... 1 0 0 0 4

3745 ( 1 )...... 1 0 0 0 1

3751 (1 )...... 1 0 0 0 2 1 _ (4)...... 1 0 0 23 9 1 1 5 1 2 15 - (5)...... 50 41 14 77 69 39 18 4 9 1 2 4

- (7 )...... 3000 1 ..

3752 (1 )...... 1 0 0 0 1 1 3768 (1 )...... 4000

- (2 ) ...... 2500 1 2 1 - (5)...... 2 0 0 0 1

- (6 ) ...... 700 9 1 1 13 14 3

- (1 0 ) ...... 600 2 1 1 - (13)...... 300 1 - (14)...... 600 8 5 7 13 1 0 3 1

- (1 5 )...... 500 8 6 1 2 25 4 5 1 - (16)...... 400 6 1 4 7 2 8 4 2

- (17)...... 300 1 2 2 2 3 15 2 3 1

- (18)...... 1 0 0 13 2 1 4 2 0 1 2 4 8 13

3782 ( 1 )...... 1 0 0 0 2

3788 (1 ) ...... 1 0 0 0 4

3789 ( 1 ) ...... 1 0 0 0 1

- (6 ) ...... 1 0 0 0 1

3792 (1 ) ...... 1 0 0 0 2 3800 (3)...... 300 19 3 3 5 2 5 7 13

3804 (1 ) ...... 1 0 0 0 1 2

- (2 ) ...... 600 54 24 1 1 8 1 1 - (4 )...... 1 0 0 15 1 2 2 2 15 5

3814 ( 1 ) ...... 600 / 2 1 5 4 1

- (2 ) ...... 300 20 20 2 1 1 2 4 3 3 3 _ (3)...... 100 55 13 4 6 30 2 20 2 20 1 50 13 - (4)...... 50 15 8 2 1 15 3 1 7 1 2 5 67 52 2 *

3821 (1 )...... 1 0 0 0 2 2 3828 (1 ) ...... 300 14 6 3 1 1 2 1 7 95 39 - (4)...... 1 0 0 35 14 13 1 0 29 4 1 0 6 5 1 262 35

- (6 )...... 3500 1 1 - (9)...... 2000 1 2 - (13)...... 1500 5 4 - (14)...... 1000 / - (15)...... 600 1 - (19)...... 50 14 4 2 7 3830 (5)...... 1000 5 3844 (5)...... 1000 4

3847 (1 )...... 35 0 0 1 - (3)...... 2500 4 1 - (4)...... 2000 23 12 4 3 1 21 8 - (5)...... 1500 3 1 3893 (1)...... 500 1 1 - (3)...... 300 9 10 4 3 3 2 13 - (6)...... 800 10 6 4 2 1 3 - (7)...... 600 15 2 4 3 1 1 1 1 1

- (8 )...... 100 5 1 4 6 1 1 1 3 3 - (9)...... 50 39 5 28 13 1 3 1 4 2 3902 (3)...... 600 10 13 1 1

- (4)...... 100 23 5 14 6 1 - (5)...... 50 90 13 5 1 3 5 3

3903 (2 )...... 600 9 13 2 1 2 - (3)...... 300 13 3 15 9 2 4 5

- ( 4 ) ...... 1 0 0 34 8 24 1 0 2 2 8 13 6 - (5)...... 50 9 1 2 24 16 10 3 .. 1 2 6 sedenloria atlantica solit. pacifica colletli curviiies elongata ^tntion MAY. stebbinfii f ni f ni t f m f m f m f 1 ni f m

3904 (2 ) ...... 3000 2 2 2 1 - (4)...... 2 0 0 0 2 1 2 - (5)...... 1500 6 surface 1

1 0 3905 (2 ) ...... 600 13 4 1 4 _ (3)...... 400 1 1 7 9 2 2 2 1 - (4)...... 300 9 3 5 2 - (5)...... 1 0 0 51 2 5 5 5 1 1 2

3906 (2 )...... 600 3 3 - (3)...... 400 1 3 2 1 1

1 0 0 0 1 3907 (1 ) ...... _ (3)...... 400 2 0 2 8 3 1 1 1 - (4)...... 300 8 7 5 7 7 2 1 - (5)...... 1 0 0 1 1

3908 (2 ) ...... 600 13 1 1 2 1 - (3)...... 400 6 1 2 3 2 - (4)...... 300 6 4 2 3 3909 (4)...... 3000 1 1 3910 (4)...... 1 0 0 6 3 1 5 6 3910 (5)...... 50 4 - surface 1 3912 (3)...... 300 5 3 2 0 4 1 3914 (3)...... 300 14 8 1 1 - (5)...... 50 24 3 1 1 1 3915 ( 1 ) ...... 1 0 0 0 1 ~ (5)...... 50 29 6 2 4 81 59

3916 (1 )...... 1 0 0 0 3 1

- (2 )...... 600 7 3917 (3)...... 3200 2

- (1 0 )...... 50 1 0 1 37 42 1 1 5 1 3918 (5)...... 50 3 61 26 2 1 14 135 98 177 95 2 .. 1 .. 3920 (1 ) ...... 4000

- (2 ) ...... 3500 7 1 1 2 2 3 1 / 5 ~ (4)...... 2500 2 1 1 3 3 2 - (5)...... 2 0 0 0 3 2 2 1 4 2

- (6 ) ...... 1 0 0 0 4 1 2 1 1 1 1 7 8 - (7)...... 600 3 4 1 2 3 1 1 4 1 0 4

1 1 2 4 2 3921 (1 )...... 1 0 0 0 - (3)...... 300 6 1 1 5 14 1 2 1 0 0 0 1 3922 (1 ) ...... 2 - (2 ) ...... 600 1 2 1 1 2 3924 (1 ) ...... 1 0 0 0 1 1 0 1 3 1 1 1 1 3925 (1 )...... 1 0 0 0 - (2 )...... 600 1 8 2 3 - (3)...... 300 2 1 5 4 5 6 19 1 4 - (4)...... 1 0 0 1 0 3 1 1 9 19 18 27 5

3933 (2 )...... 3500 2 1 3 1 - (3)...... 3000 2 3943 (i) ...... 500 1 50* 3947 (1 )...... 400 17 4

3948 (1 )...... 500 1 1 1 2 2 3949 (1 )...... 1 0 0 0

- (2 )...... 600 4 1 - (4)...... 1 0 0 1 5 2 1 25 - (5)...... 50 4 105 61

1 0 0 0 3951 (1 ) ...... 1 1 - (2 )...... 600 - (3)...... 300 1 1 1 - (4)...... 100 4 2 1 1 1 11 13 atlantica pacifica colletti caroipes Station M.W. sedentaria solil. stebbingi elongata I f ni f f f t t m t 1 1 1 1 m

3957 (1 )...... 500 1 7 2

3959 (1 )...... 500 1

3962 (1 )...... 1 0 0 0 1 1 2 1

- (2 )...... 600 2 4 1 1 3 2 2

- (3)...... 300 2 2 1 3 1

- (-1)...... 1 0 0 17 1 2 !) 7 4 1 6 1 133 30 - (5)...... 50 9 4 5 4 4

3964 (1 )...... 1 0 0 0 1 1

- (2 )...... 600 3 1 5 2 2 - (3)...... 300 1 3 2 1 2 3 4

- (5)...... 50 2 2 2 0 30 6 2 1 1 1 2 1 0

- (6 )...... 3000 1 2 . .

(8 )...... 2 0 0 0 1 2 1 1

- (9)...... 1500 1 1 1

- (1 0 )...... 1 0 0 0 3 3 1 . .

3969 (2 )...... 600 2 1 - (3)...... 300 5 2 1 4 1

- (-1)...... 1 0 0 4 5 5 1 1 2 - (5)...... 50 6 2 2 2 1 3 1 1 3971 ( 1 )...... 1 0 0 0 2 1 2

- (2 )...... 600 1

- (3)...... 300 1 3 .. 8 1 2

— (-1) ...... 1 0 0 3 3 1 1 2 2 9 1

East Atlantic (Cap e To\\n -Gibral tar) (C(jmplete materi al) 3975 (1 )...... 3000 1

- (2 )...... 2500 1 2 6 1 - (3)...... 2 0 0 0 4 2 7 4 - (4)...... 1500 3 1 - (5)...... 1 0 0 0 1

(8 ) ...... 300 1 - (9)...... 1 0 0 3 1

3978 (1 ) ...... 1 0 0 0 1 1 1

- (2 )...... 600 2 1 1 2 - (3)...... 300 - (O)...... 5000 1

- (8 )...... 3000 1 1 - (9)...... 2 0 0 0 1

- (1 1 )...... 1 0 0 0 3 1

3979 (1 ) ...... 1 0 0 0 1

- (2 )...... 600 3 1

- (-1 )...... 1 0 0 1 - (5)...... 50 2 1 3980 ( 1 ) ...... 1 0 0 0 3

- (2 )...... 600 13 4 2

- (3)...... 300 2 3 4 1 7 3

- (5)...... 50 6 3 1 1 2 - (7)...... 5000 1 2 1 1

- (8 )...... 4000 2 - (9)...... 3000

- (1 0 )...... 2000 2

- (1 1 )...... 1000 11 1 2 2 3981 (3)...... 300 4 1

3996 ( 1 ) ...... 4000 4 1 1 2 4 1

- (2 ) ...... 3000 7 7 2 1 2 1 0 - (3)...... 2 0 0 0 1 8 6 1 1

- (4)...... 1500 8 34 4 1 2 15 4 - (5)...... 1 0 0 0 36 29 7 3 4 4 2 1 1 - (6)...... 1000 3 2 1 sedeintaria alianiica solil. pac ifica col.klti curvipes slebbingi einngala Station M.W. f m f m f f m I m f m f m f III

3996 (V)...... 600 2 2 4 2 4 2 4 16 1 1 1 - (8 )...... 300 1 1 1 1 4 3 2 2 2 - (9)...... 1 0 0 4 1 4 2 1 2 5 3 34 14

- (1 0 )...... 50 6 1 14 3 6 1 7 1 0 109 70

3997 (2 )...... 600 1 3

3998 (1 )...... 1 0 0 0 1 2 3

- (2 )...... 600 5 1 1 1 1 70 15 - (3)...... 300 5 7 3 63 16 _ (4)...... 1 0 0 64 99 45 16 7 23 38 9 - (5)...... 50 1 1 164 78 96 37 28 1 2 75

- surface 2

- (6)...... 6000 1 2 - (7)...... 5000 1 1 1 42 0

- (8 )...... 4000 1 2 35 18 - (9 )...... 3000 1 1 1 17 5

- (1 0 )...... 2 0 0 0 1 23 7

1 0 0 0 - ( 1 1 )...... 1 1 1 43 23 1 0 0 0 3999 (1 )...... 1 2 1 - (3)...... 300 5 1 1 7

2 4000 (1 ) ...... 1 0 0 0 4 3 .. 1 4 2

_ (2 )...... 600 35 1 2 .. ' 2 1 1 2 41 - (3)...... 300 78 60 4 14 1 1 0 6 2 3 1 134 46 _ (4)...... 1 0 0 32 17 1 1 6 8 4 109 1 1 48 49 3 1 - (5)...... 50 52 64 38 2 0 2 0 869 64 1 2 2 6 4

- surface 1 - (6)...... 6000 5 2 1 - (7)...... 5000 1 2 6 1 5 1 2 1 2 - (8 ) ...... 4000 4 2 0 1 1 1 / (9)...... 3000 5 4 1 2 1 8 1

- ( 1 0 ) ...... 2 0 0 0 1 2 5 1 1 4 1 1 1 17 1

1 0 0 0 6 1 1 1 - ( 1 1 ) ...... 18 2 2 1 1 1 0 4001 (3)...... 300 1 .. 3

4003 ( 1 ) ...... 6000 1

- (2 ) ...... 5000 1 - (3)...... 4000 1 1 1 - (4)...... 3000 - (5 )...... 2 0 0 0 1 1 1 1 - (6)...... 1 0 0 0 1 2 1 1 1 - (V)...... 1 0 0 0 1 1

- (8 ) ...... 600 5 8 1 3 - (9)...... 300 2 19 1 2 1 1

- (1 0 ) ...... 1 0 0 7 26 1 0 13 1 7 38

- (1 1 ) ...... 50 1 31 18 7 5 4004 (3)...... 300 1 2 1 - (4)...... 1 0 0 1 1 1 2

- (5)...... 50 1 1 1

4005 ( 1 )...... 4000 1 1 1 - (2 )...... 3500 2 3 1 1 1 1 1 - (3)...... 3000 2 1 1 2 - (4)...... 2500 1 3 5

- ( 5 ) ...... 2 0 0 0 3 2 0 1 1 1 0 1

- (6)...... 1 0 0 0 15 6 1 - (7)...... 1 0 0 0 1 1 2

- (8 )...... 600 2 3 1 5

- (9)...... 300 2 1 1 1 1

- ( 1 0 ) ...... 1 0 0 1 1 6 5 1 8 1 2 - ( 1 1 ) ...... 50 1 0 4 3 1 15 2

- surface 1

4006 (I)--.- 1 0 0 0 4 1

- (2 )...... 600 6 colletti curvipes stebbingi elongata station M.W. sedentaria allantica solit. pacifica ni i f m f m t m f m f m t f 1

4006 (3)...... 300 19 1 2 46*

- (5)...... 50 8 1

4007 (1 ) ...... 1 0 0 0 3

- (2 ) ...... 600 27 23 1 3 1 - (3)...... 300 45 9 4 3 1

- (4)...... 1 0 0 31 28 14 2

- (5)...... 50 15 7 1 9 2 1

- (6 ) ...... 4000 6 1 3 1 1

- (7)...... 3500 6 3 3 2 1 1

- (8 ) ...... 3000 3 3 1 1 1

4007 (9)...... 2500 1 2 1 0 1 1

- ( 1 0 ) ...... 2 0 0 0 7 4 1 1

- ( 1 1 ) ...... 1 0 0 0 8 5 1 1

4009 (1 ) ...... 1 0 0 0 I 1

- (2 ) ...... 600 2 1 18 1 3 1 5 2

- (3)...... 300 9 2 4 2 1 7 1 7 3

- (4)...... 1 0 0 65 3 2 1 7 1 2 0 4

- (5)...... 50 11 4 1 9 1 4 1 - surface . . 1

- (6 )...... 4000 3 1

- (7)...... 3500 6 1 37 14 2

- (8 )...... 3000 4 4 33 18 1 4 1 - (9)...... 2500 3 3 3 5 1

- ( 1 0 )...... 2 0 0 0 8 1 1 2 2

- ( 1 1 ) ...... 1 0 0 0 73 31 3 1 1 15 2 6

4010 (1 )...... 1 0 0 0 1

- (2 )...... 600 1

- (3)...... 300 13 .. 1

- (4 )...... 1 0 0 13 1

- (5 )...... 50 3 1

4014 (1 ) ...... 1500 6 1

- (2 ) ...... 1 2 0 0 15 16 1 3

- (3)...... 900 30 3 3 1 1 - (4)...... 600 315 185 n 17 41 3

- (5)...... 300 1 1 1 1 1

- surface 1 3

4017 (1 ) ...... 5000 7 3 1 2

- (2 )...... 4000 4 2 1 2 8 2 4 2 1

- (3)...... 3000 4 13 48 26 1 1 2

- (4)...... 2 0 0 0 2 2 51 14 13 1 3 2

- (5)...... 1500 57 27 3 2 1 1 2 1 3 1

- (6 )...... 1 0 0 0 174 117 5 7 3 1 1 1

- (7)...... 1 0 0 0 23 2 2 1

- ( 8 1 ...... 600 231 1 0 0 15 3 13 9 5 1

- (9)...... 300 89 34 7 6 3 9 45 1

- ( 1 0 ) ...... 1 0 0 197 72 32 23 3 16 3 3 19 15

- ( 1 1 ) ...... 50 213 2 0 24 1 1 14 1 1 9 3

4018 (1 ) ...... 1 0 0 0 15 1 3 4 2

-(2 )...... 600 15 7 3 1

- (3 )...... 300 5 7 1

- (4)...... 1 0 0 3 3

- (5 )...... 50 2

4019 (1 ) ...... 4000 1 0 1 4 4 2 1

- (2 ) ...... 3500 1 0 1 0 4 1 2 1 3 1

- (3 )...... 3000 19 14 3 9 1 1 1 2 2

- (4)...... 2 0 0 0 1 1 25 5 2 1 1 1 C 2 - (5)...... 1 0 0 0 123 44 2 5 1 1 1 1

- (6 )...... 1 0 0 0 1 1 1 1 - (7)...... 600 32 53 2 1 1 sedenlaria atlanlica solil. pacifica collelli carvipes slebbingi elongala station M.W. f ni f m f I f m f I m f m f

4019 (8 ). 300 220 103 12 20 10 38 » - (9)­ 100 230 I 13 19 6 3» - (10). 50 133 I 4 26 15 4* surface 1 4022 (1). 100 - (2). 50 4023 (5). 500 13 - (6). 400 21 - (7). 300 38 - (8). 200 47 4025 (9). 400 - (11). 200 1 - (14). 600 9 11 - (15). 300 11 10 - (16). 100 1 5 - (17). 50 4 3

Mediterranean Sea (Selected samples mostly from deep hauls) 4026 (1)...... 200 1 4027 (1 + 4 )...... 200 1

4035 (8 ) ...... 50 4 4050 (1)...... 3000 3000 54 54 50 13 13 - (2)...... 2500 2500 13 13 11 14

■- (3)...... 2000 2000 15 15 9 5 8

- (4)...... 1500 1500 10 10 6 4 7 - (5)...... 1000 1000 14 14 12 2 10 surface 3

- (20). 1 0 0 3 21 o - (21). 50 1 17 16 - (22). 300 29 41 - (23). 250 13 26 - (24). 200 3 17 14 - (25). 150 6 18 9 4051 (18). 600 13 - (19). 300 2 - (21). 50 1 4052 (18). 200 3 - (19V 150 2 4062 (1). 1000 3 - (2). 600 6 4063 (1). 1000 8 4065 (1). 1000 2 - (3). 600 3 4067 (9). 1000 6

- (11). 600 3 4069 (9). 1000 1 4070 (5). 2000 3 - (15). 1000 1 - (16). 950 1 - (21). 1000 10 14 4071 (6). 1000 3 1 4075 (9). 1000 1 1 4076 (1). 1000 52 - (-4). 400 1 - (19). 600 3 4089 (9). 1000 3 sede ntaria atiantica solit. pacifica collelti cunvipes stebbingi elorigata M.\V. f m f Hi f f 1 ni f 1 ni f m t m f ni

4089 (11).. 600 4

4119 (1).. 1600 6 8 9 7 1 64 13

- (2).. 1500 i 3 2 4 15 4

- (3).. 1 2 0 0 1 1 1 2 3 4 26 5

- (4).. 1 0 0 0 7 8 3 19 1 0 - (5).. 1 0 0 0 28 5 27 18 58 15

- (6).. 800 2

- (10).. 4000 1 8 6 - (11).. 3000 2 4 2 3 1 - (12).. 2 0 0 0 3 3 1 4 4 - (13).. 1500 2 8 5

- (14).. 1 2 0 0 2 2 4 4 3 192*

- (15).. 1 0 0 0 1 1 2 - (17).. 600 4 4136 (10).. 950 5

4139 (1).. 1 0 0 0 23 - (2).. 950 1 1 4110 (3 + 7). 20(1 5

XortheasI Atlantic (Compli?te mat erial)

4141 (1)...... 500 1 - (2)...... 400 3

- ( 3 - 6 ) ...... 300 2

4147 (6) ...... 1 0 0 0 9 - (7)..'.... 950 4 - (9)...... 300 4 4149 (1)...... 1 0 0 0 2 (2)...... 950 2 (3)...... 600 7

(5 ) 1 0 0 1 2

(6 ) 50 2 2

4157 (3 ) 600 1 4158 (IJ...... 250 2 (4 ) 1 0 0 1

(6)...... 1 0 0 0 2 O)...... 950 1 (1 7 )...... 1500 2

C. Dana Expedition 1931 (For data on hauls cf. Taning 1944).

sedentaria atlantica solil. pacifica colletii curvipes stebbingi elongata Station M.\V. t m f m f f m I m f m f m f m

North Atlantic (Co;mplete materia 1)

4185 (1)...... 800 2 1 2

4192 (1)...... 1 0 0 0 1

- (2 ) ...... 600 28 48 30 4 3 1

- (3)...... 300 46 7 79 3 4 2 4 9 1

- (4 )...... 1 0 0 15 4 6 2 1 2 2 2

- (5 )...... 50 46 2 2 2 1 2 30 3 1

- (6)...... 500 1 0 1 55 1 0 4 1 - (7)...... 400 3

4195 (1)...... 1 0 0 0 2 1

- (3 )...... 300 17 1 1 6 3 2 8 6

- (4 )...... 1 0 0 41 2 7 1 4 1 2 1 1 2 1

- (5 )...... 50 95 7 25 13 1 1 17 2 5 1 6 3

- (6)...... 300 1 1 sedeiilaria alianlica solit. pacifica colletli curi'ipes s ta tio n M.W. slebbingi elongata f m f m t f m f m f m f m f m

4197 ( 6 ) ...... 1 0 0 0 14 - (7 ) ...... 600 3 250*

(8 )...... 300 3 1 3 _ (9)...... 1 0 0 2 0 1 32 14 5

- (1 0 ) ...... 50 9 50 15 36 4201 (16)...... 6000 1 1

-(2 0 ) ...... 2 0 0 0 2 1 4203 (1)...... 1 0 0 0 1 1

- (2 ) ...... 600 2 - (3)...... 300 4 - (4)...... 1 0 0 1 1 2 4 - (5)...... 50 2 30 7

D. California Coopera ve Oceanic Fisheries Investigations (CCOFI), Cruises 1, 5, 9, and 20. (For data on hauls see Universit of California, Scripps Institution of Oceanography 1949a and b, 1950 and 1951).

sedenlaria atlantica solit. pacifica collelli curvipes stebbingi elongala Station Date I m f m . t t m f m t ni f m f m

110 13. 7.49 1 1 202 20.11.49 3 203 10. 7.49 1 - 20.11.49 1 204 10. 7.49 1 205 11. 7.49 1 - 9.11.49 1 1 1 206 11. 7.49 1 207 18.11.49 1 1 208 12. 7.49 - 18.11.49 1 209 12. 7.49 4 2 - 17.11.49 1 210 12. 7.49 2 - 17.11.49 1 301 23.11.49 1 302 23.11.49 1 303 24.11.49 1 304 8. 7.49 1 - 24.11.49 1 1 305 8. 7.49 1 306 7. 7.49 1 - 25.11.49 2 2 7 307 - 7 4 3 5 308 7. 7.49 3 1 - 25.11.49 3 10 309 7. 7.49 1 1 3 310 16.11.49 13 20 6 6 401 2. 7.49 5 402 2. 7.49 5 403 13.11.49 1 1 406 4. 7.49 1 1 407 4. 7.49 2 1 7 2 - 14.11.49 3 1 5 3 408 4. 7.49 4 4 - 14.11.49 1 1 409 5. 7.49 4 10 5 2 410 5. 7.49 9 10 5 3 sedenlaria atlantica solit. pacifica colletli curvipes slebbingi elongala station Date f m i m t t m t m t m 1 m 1 m

410 15.11.49 2 13 13

503 9.11.49 1 2 2

506 4. 7.49 1 1

- 11.11.49 1

507 4. 7.49 1 1 1 1 0 508 4. 7.49 2 7 1

- 11.11.49 1 1 509 4. 7.49

- 11.11.49 1

510 5. 7.49 1 1

- 11.11.49 1 1

601 14.11.49 1

604 13.11.49 1

606 6 . 7.49 1

607 6 . 7.49 2

608 6 . 7.49 2 1

609 6 . 7.49 3 7

- 12.11.49 1

610 5. 7.49 4 1

- 12.11.49

701 16.11.49 2

702 7. 3,49 1 14 6

704 17.11,49 1

801 13, 7.49 1 - 21.11.49

802 15. 3.49 1 1

- 13. 7.49 16 13

803 13. 7.49 1 1 1

- 20.11.49 1

804 15. 3,49 1 4

- 20,11.49 1

805 15. 3.49 2

- 12. 7.49 8

- 20.11.49 2 806 14. 3.49 5

807 14. 3.49 1 4

- 12. 7.49 1 1 808 14, 3,49

810 11, 7,49 1

901 1. 7.49 1

902 1. 7.49 1

- 19.11.49 1

903 1. 7.49 1

906 2. 7.49 1

908 3. 7.49 1 910 3. 7.49

911 4. 7.49 1

1 0 0 1 7. 7.49

1 0 0 2 7. 7.49 1

1004 6 . 3.49 4 1

1006 5. 7,49 1

- 15,11,49 1

1009 4, 5, 3,49 1

- 16,11.49 1

1061 14.11.49 1

1 1 0 2 8 . 7.49 1

_ 13.11.49 1

1103 8 . 7.49 1 1

1104 8 . 7.49 1

- 13.11.49 1 1 ntlanlica solil. pacifica coHelli curuipes elongala f m ( ni t ! t m t m f f m

1106 9. 7.49 1202 12. 7.49 1203 12. 7.49 9.11.49 1204 12. 7.49 9.11.49 110.35 20.11.50 120.45 11.11.50 120.60 11.11.50 120.80 12.11.50 120.90 12.11.50 130.35 14.11.50 130.40 14.11.50 130.110 13.11.50 140.35 20.11.50 157.20 28.11.50

E. Longlining Stations (For data on hauls cf. Wilson and Shimada 1955).

sedentaria atlantica solil. station Dale pacifica colletli curripes slebbingi elongata f m f m t I m f m I m f m 1 m

1 31. 1.53 4 3 5 5 3

2 2. 2.53 3 1 4 4 1 37 38

4 4. 2.53 1 1 3 2 1 3 1

5 5. 2.53 1 1 1 3 3 3 1

6 6 . 2.53 1 1 7 4 7

7 8 . 2.53 1 2 1 7 3 1 0 13

9 10. 2.53 1 .. 1 1 3 4 3 2

1 2 15. 2.53 1 4 2 1

14 17. 2.53 2 1 5 5 54 46 8 2

16 19. 2.53 3 1 3 1 0 4 2 1

18 21. 2.53 1

2 0 26. 2.53 1

2 2 28. 2.53 1 2 1

24 2. 3.53 2 3 1 2 1 2 9 16 6

25 3. 3.53 1 1 1 15 13 3

26 4. 3.53 1 1 2 2 9 3 1

F. Barbados Collection (taken at waters 5-10 miles off western coast).

Depth sedentaria atlantica solit. pacifica colletti curvipes slebbingi elongala Dale Time (m) f m f m f f m f m i m i m f 1 m

1.12.58 21:03 29.2 4 2 18.12.58 10:50 68,4 - 11:45 38,6 4

13. 1.59 21:05 37,5 1 27. 1.59 21:15 34,2 3

9. 2.59 10:04 112,4 1 - 11:37 35,9 3

13. 2.59 21:05 17,4 1 1 13. 3.59 20:30 surface 3 - 21:07 30.9 1 0 15 2 Depth sedeiitaria allanlica solit. paciftca collelti cunr/pes slebl)ingi elonigata Date Time (m) { m f I m f t m f m t m t tn f m

19. 3.59 09:25 136.2 2 2

- 10:17 78.0 2

- 1 1 : 0 1 24.2 1 5

10. 4.59 21:09 surface 1

24. 4.59 20:57 36.3 1

29. 4.59 09:06 187.8 1 1

- 09:55 136.2 1 1 - 10:40 81.3

- 1 1 : 2 0 47.0 1 1

29. 5.59 20:45 47.0 1 12. 6.59 21:16 32.6 24. 6.59 09:20 193.9

- 1 1 : 0 2 78.1 1

- 11:44 35.8 1

26. 6.59 2 0 : 0 0 surf. 20.10.59 11:08 2H9.2 - 13:55 90.8

13.11.59 20:28 50.0 1

30.11.59 20:23 48.5 1 14.12.59 - 61.6

16.12.59 12:40 112.4 1 - 14:05 47.0

29.12.59 20:16 54.5 1

18. 1.60 2 0 : 2 0 surf. 1 - 20:19 48.5

2 0 . 1.60 12:42 1 0 0 . 0 1

1 . 2.60 20:18 42.3 4 - 20:59 surf.

18. 2.60 12:53 192.8 1

15:08 surf. 1 29. 2.60 21:15 surf. 4

- 20:35 57.4 1

14. 3.60 20:30 surf. 1 1

16. 3.60 1 1 : 2 2 314.0

25. 4.60 •? 23.4 2

9. 5.60 2 0 : 2 0 20.5 1 2

24. 5.60 2 0 : 1 1 32.6 35 2 2

- 20:57 surf. 1 3 20. 6.63 20:25 19.5

20. 6.63 2 1 : 0 0 14.5 1 2. 7.63 10:30 70.0 1 4. 7.63 13:55 100.0 - 14:15 97.0 1 8. 7.63 15:00 50.0 1 1 12. 7.63 19:45 25.0 3 1 - 20:10 50.0 1 2 2 16. 7.63 20:25 26.0 10 5 1 - 21:00 30.0 1 3

22. 7.63 19:45 2 2 . 0 1

- 2 0 : 2 0 28.0 1 2

29. 7.63 19:45 50.0 1

- 20:25 1 0 0 . 0 1

6 . 8.63 20:06 1 0 0 . 0 1 G. Collection of the Zoological Museum, University of Copenhagen.

sedenlaria atlanlica solil. pacifica colltlli Dale Locality curvipes stebbingi elongata I I m f m I f I m f m f I m t f m

3.11.50 Galathea si. 8 400-1200 M.W. 16. 2.51 Galalhea st. 199 1500-1700 .M.W. 24. 3.51 Galathea st. 263 3000 M.W. 27. 3.51 Galalhea st. 266 7000 M.W'. 14.10.51 Galathea st. 518 8800 .M.W. 5. 6.20 Dana st. 851 50 M.W'. 25. 6.32 Dana st. 4402 600 M.W. 62°23' 16°05' (N) (W) 20. 3.33 Dana st. 4773 200 M.W. 32“57' 128°48' (N) (W)

Mediterranean (N) (E) 6.4.1911 33°15' 27°30' 20.3.1881 38=33' 26°46' (N) (W) 17.12.1868 36°29' 2°05'

Atlantic 3.8.1947 44° 37° 1 1866 43=30' 32=40' 1 1866 43=10' 34=01' 1

1867 43= 1 2 ° 13 1862 42°50' 46=10' 1 1861 42= 46° 1 1863 41°35' 14°19' 26.7.1949 38° 40° (N) (E) 7 38°10' 15°30' (N) (W) 1863 36=22' 40°48' 15 1866 35=29' 38=16' 7 34=22' 18=10' 1863 34=10' 42°10' 1862 33=40' 72=46' 1862 33=06' 25°30' 1862 33=01' 25=30' 17.7.1949 33° 47= 1866 32°16' 38°01' 1870 32= 23° 1862 31°30' 26=20' 1867 31°30' 19°20' 1862 31°28' 29=39' 1863 31° 40= 1862 30°34' 30=50' 1862 30=18' 28=10' 7.7.1896 30°06' 18°38' 1883 30° 19° sedt nlaria allanlica solil. pacifica COlletU curvipes sleb'bingi eloitgala Date Locality f m f 1 m f f 1 m f m f m f m f m

(N) (W)

1862 29“ 29=54' 1

1862 29" 2 0 ° 2 1

1870 28=12' 28=30' 7 2 4

1866 28° 42=30' 1

1882 28= 25=40' 1 7.12,1895 26=15' 20=56'

1871 26= 26= 1 4

1863 25= 34= 1 1871 24° 31 = 1870 23=32' 35=18'

1872 22=40' 48= 1

9 2 2 = 2 2 = 1 >8.12.1880 21=40' 29=40' 1882 21=16' 65=08'

9. 9.1871 2 0 = 30= .. 1

(1.12.1880 19=52' 31=10' 1 3.12.1895 19=48' 36=15' >0. 4.1870 19= 36=30' 4 18&1 19\S0' 26=05' 7 4

>9. 4.1882 18=17' 54=14' 1 1

1866 16=31' 33=10' 1

>4. 1.1881 16M0' 25=40' 6 3 1

?. 1.1881 16= 40= 1

1866 15=56' 30=41' 4 2

1864 14=46' 28= 2 5

1864 13=10' 27=30' 2 3

1864 11=30' 27=30' 1

9 1 0 =2 2 ' 26=16' 1 1

4. 7.1852 9= 30= 1 1

1. 5.1860 5= 32= 1

7.12.1876 5= 26=30' 1

1866 4=56' 27=51' 1 (S) (W)

1863 1 = 31=10' 1

1863 6=40' 32=20' 1

1864 8 = 13=20' 1

1864 1 0 = 1 2 = 1

1864 1 0 =2 0 ' 5= 2

1864 17=30' 2=40' 2 1872 19=30' 2=30' 1864 21=30' 28= 3

1867 20=14' 1=04' 1 (S) (E)

1862 26=30' 8 =2 0 ' 1 1 (S) (W)

? 28= 28= 1

1869 30=15' 20=40' 1 1869 31=30' 19=30' 4

0. 4.1872 30=30' 22=30' 1 (S) (E)

0 . 1,1862 32=30' 19= 3 (S) (W)

1869 33=30' 1 1 = 7 1

1864 34=50' 4=30' 1 1 (S) (E)

? 37= 1 2 = 9

1864 37=40' 1 2 = 2 3 sedeiilaria at sol it. pacifica colleili curpipes slebbingi elongata Date Locality t m t f f m m f I m f m

Indian (S) (E)

? 34“50' 25=30' 1 1862 35°36' 27=40' 1862 38°29' 29=20' 5

1862 35°30' 29=30' 1

? 38“20' 30= 2

1870 33=30' 32=30' 1 1869 33°20' 33=

1864 38=20' 36= 2 1864 34= 36°

1864 38=20' 38= 1

1869 39=56' 40=26' 1 1869 39=55' 41=30' 14 1864 39=50' 41=30' 4

■J6.10.1881 30=12' 44° 1

1870 31=35' 45=17' 6

1861 37= 49=20' 1

1869 37= 50= 8

1862 36=50' 50=30' 6 1869 35= 55= 3

1861 32=40' 55=20' 1

1864 2 1 = 57= 1 1864 23=40' 57=40' 2 1864 26=30' 58= 17

1864 27=40' 58=30' 1 1869 38° 62=30' 12.5.1880 21=50' 63=40'

1870 22=40' 81=56' 2

1869 22=30' 87= 1

1864 30= 96° 2 1870 28“15' 97=36' 2 1870 27= 101=40' 4

1870 24=50' 102=50' 1 1870 15=35' 109=20' (N) (E)

17.9.1881 3=02' 110=40' 1 (S) (E) 1870 39=56' 112=30' 3 (N) (E)

11.3.1914 7=12' 123= 2 Mortensen ,50 M.W. (S) (E)

11.9.1914 38=05' 149=45' 1 Mortensen 50 .M.W. H. The re-identification of the so-called male Phronima coUetti taken by the “Thor” from the Mediterranean (For data on hauls cf. Stephensen 1924).

Thor Station M.W. P. colletti P. curvipes

50 1600 1

108 25 - 1

1 1 2 300 - 3

116 25 - 1

118 7 - 1

1 2 1 25 1 -

133 300 - 1 134 300 - 3 205 25 - 7 206 300 - 1 36 ViLTER, V.: Bases cyto-architectoniques de 46. *C0 i.iTiCB0 , B ernardo: Contributo staUsUco 64. *Y o d n o , R ic h a r d E.; A note on three spec^ ’ I’acuiU vlsuelle che* un poisson abyssal, ad un tentativo dl discrimlnazione biometrica mens of the squid Lampadioteulhii megaleti le Lampcaiyetus eroeodtlu*. Compt. rend. dl popolazionl o razze geograflche dl teleostei B e r r y , 1916 (Cephalopoda: Oegopslda) froa Soc. Blol. 146. 3 pp. Janvier 1951. del genere "Bregmaeeros". Acad. Naz. Dei the Atlantic Ocean, with a description of tlM UnceL Serie VIII, 19. 9 pp. 1955. Roma. male. BuU.Mar. ScL Gulf and Carib. 14, p g 87. *Pabh, Alb. Eidb: Preliminary revision of the 444-452, 1964. " Alepocephalldae, with the introduction of 47. *DB S y l v a , D o n a l d P.: Systematlcs and life a new family, Searsldae. American Museum history of the great barracuda, Sphyraena 66. *R a m p a l , J e a n n in b : Variations morphologl; Novitates. No. 1531. 21 pp. 1951. New York. barracuda CWalbaum). Stud. tiop. Oceanogr. ques au cours de la crotssance d’Euelio cusps Miami, 1. 179 pp. October 1963. Miami data (Bose) (Pt^pode Thteosome). BuID 38. *Sbars, Maby; Notes on siphonophores. 3. Nee- Inst. O c^o g r. <6, 1360. 12 pp. 1965. Mon topgramis splnosa n. sp. Breviora Mus. Comp. 48. * P b t b r s b n , K. V ^.: On some medusae from naco. Zool. No. 3. 4 pp. 1952. Cambridge, Mass. the North Atlantic. Vld. Medd. Dansk naturh. Foren. 119. 1957. Copenhagen. 65. *G ib b s J r ., R o b e r t H . and St a n l e y W E r r a 39. *Pabb, Alb. E ide: Review of the deep-sea m a n : Cryptostomias psgehnlutes, a new fishes of the genus Asquamieept Zdomaybr, genus and spedes of astronesthid fish trooB with descripUons of two new species. Ame­ 49. •GijNTHER, K. & D eckert, K.: Ober die syn- kranialen GefSflstdmme des Tlefseeflsches the southwestern Padfic Ocean. VideasJol rican Museum Novitates. No. 1655. 8 pp. Medd. fra Dansk naturh. Foren., 128. 7 ppq 1954. New York. Mataeofteus niger Ayres (Isospondyli, Ma- lacosUldae). ZooL Bdtr&ge. N. F. £. 15 pp. 1965. Copenhagen. 40. *Faob, Lftuis: Les AmpUpodes pOagiques du 1956. BerUn. 67. *M u n k , O l e : O n the retina of Diretmus argear genre Rhabdosoma. Compt. rend. ston. Acad. teas J o h n s o n , 1863 (Diretmldae, Pisces). W Sc. 289. 3 pp. 1954. Paris. 60. *JoNES, S. and M. Kumaran: Distribution of densk. Medd. fra Dansk naturh. Foren., Itli larval bUlflshes (XiphlidaeandlsUophoridae) 8 pp. 1966. Copenhagen. 41. *ViLTBB, V .! Existence d’une r6tlne k plu- in the Indo-Paciflc with spedai reference to sieurs mosalques photorfeceptrices, chez un the collections made by the Danish Dana 68. *M u n k , O l e : Omosudis lowei GO n t h e r , 1887C poisson abyssal bathypiiagique, BaUiglagus Expedition. Symposium on Scombroid Fishes. a bathypdagic deep-sea fish with an almOH benedicti. Compt. rend. Soc. Biol. 147. 3 pp. 1962. Part I, pp. 483^98. Mar.BloLAss. India, pure-cone retina. Vidensk. Medd. fra Dansli Dteembre 1953. Mandapam Camp. 1964. naturh. Foren. 128.15 pp. 1965. Copenhagen!

42. •-Din^renciatlon fov6ale dans I’appareil visuel *1Ru n k , O i .e : 61. The eye of Stomias boa ferox 69. * H a e o b ic b , R ic h a r d L. : The stromateoid fldi d'un poisson abyssal, le Balhylagiu benedietl. R e in h a r d t . Vidensk. Medd. fra Dansk nai- genus leiehUtys: Notes and a new spedest Compt. rend. Soc. Biol. 148. 5 pp. Janvier turh. Foren. 126, 9 pp. 1963. Vidensk. Medd. fra Dansk naturh. Foren., 188 1954. 15 pp. 1966. Copenhagen. 62. *JoNES, S. and M. Kumaran: Distribution of 43. *ViLTEB,V.: Interpretation biolo^que des tra- larval tuna collected by the Carlsberg Foun­ mes photoriceptrices supcrpos^es de la ratine 60. * R o p e r , Cl y d e F. E. and R ic h a r d E. Y o u n q e dation's Dana Expedition (1928-30) from the A review of the Vaibytenthldae and an evaa du Bathylagus benedicti. Compt. rend. Soc. Indian Ocean. Proceedings of the world scien­ Biol. 148. 4 pp. Ffcvrier 1954. luatioa ol its relationship with the Chirotem tific meeting on the biology of tunas and thldae (Cephalopoda:Oegopslda). Proc. U .S 44. ‘-Relations neuronales dans la fovea b4- related species. La Jolla, Calif. 1962. FAO Nat. Mus. 128 (3612). 9 pp. 1967. WasUngtorc tonnets du Batbj/lagus benedicti. Compt. Fish. Rep., no. 6, 8, pp. 1753-1774. D.C. rend. Soc. Biol. 148. 4 pp. Mars 1954. 63. *R o p e r , Cl y d e F. E.: EnoploteuUus anapsis, a 61. * P b a s a d , R .R a o h u & P . R .S . T a m p i; A prelimti 4i. *TiNiNO, A. V e d b l : On the breeding areas of new species of enoploteuthid squid (Cephalo- nary report on the phyllosomas of the lndla:£ the swordfish (XtpMos). Papers In Miatikr ' poda: Oegopslda) from the Atlantic Ocean. Ocean collected by the Dana Expedition 1928 Biology and Oceanography to honour H e n r y Buli.Mar. ScL Gulf and Caiib. 14, pp.140-148, 30. J. Mar. bloL Ass. India, 7 (2), 1965. 7 pH B r y a n t B ig b l o w . Deep-Sea Research 1956. 1964. 1967. Madras.

THE CARLSBERG FOUNDATION’S OCEANOGRAPHICAL EXPEDITION ROUND THE WORLD 1928-30 AND PREVIOUS “DANA”-EXPEDITIONS UNDER THE LEADERSHIP OF THE LATE PROFESSOR JOHANNES SCHMIDT DANA-REPORTS; No. No. No. Vol. 1 (complete): 62 Danish kr. Z. P. J e s p e r s e n : Quantitative VoL m (complete): 77 Danish kr. 1. Introduction of the Reports from the Carls­ investigations on the distri­ 14 . Sv. G r e v e : Echo soundings, an analysis o ' berg Foundation’s Oceanographical Expedition bution of macroplankton in the resulU. 1938. 25 pp., 4 figs. 19 pis. Photo.' round the World 1928-30. 1934. 130 pp., 2 figs. different oceanic regions. 1935. Price grapiiic reprint 1959. Price 25 Danish kr. 7 pis. Price 18 Danish kr. 44 pp., 28 figs. 8 Danish kr. 1 6 . L £ o n B e r t i n : Formes nouvelles et form e‘ 2. C. T a t e Rcoan and E t h e l w y n n T r e w a v a s : 8. M aI co lm S m f t h : The sea larvalres de Poissons apodes appartenaoa Deep-sea angler fishes (Ceratloidea). 1932. snakes (Hydrophilda). 1935. au Sous-Ordre des Lyomires. 1938. 26 p p c 113 pp., 172 figs. 10 pis. Price 17 Danish kr. 6 pp., 2 flgs. 17 figs., 2 pis. Photographic reprint 1959. P rloi 3. L £ on B e r t i n : Les Poissons apodes apparte- 9 . A n t o n F h . B r o u n : Contri­ 10 Danish kr. nant au sous-ordre des Lyomires. 1934. 56 pp., butions to the life histories 16. V il h . E o e : A revision of the genus AngaitK’. 47 figs. 2 pis. Price 9 Danish kr. of the deep sea eeb: Sgna- S h a w , a systematic, phylogenetic and geogrs-i 4. E. St e e m a n n N i e l s e n : Untersuchungen ttber phobranehidae, 1937. 31 pp., phlcal study. 1939. 256 pp., 53 flgs. 6 p k l die Verbreitung, Blologle und Variation der 17 figs., 1 pi. Photographic Out ol print. Ceratien im SQdlichen Stillen Ozean. 1934. 10. LAon B e r t i n : Les Poissons reprint 1959. 17 . E. S t e e m a n n N i e l s e n : Die Ceratien des In d ^ 67 pp., 84 flgs. Price 9 Danish kr. abyssaux du genre Cyema Price 35 schen Ozeans tmd der Ostasiatlschen Gewfisseia 6. ViLH. Eob: The genus Stomias Cuv., taxonomy GO n t h e r (Anatomie, embry- Danish kr. 1939. 33 pp., 8 flgs. PhotograplUc reprint IM X. and biogeography. (Based on adolescent and ologie, blonomie). 1937. 30 Price 10 Danish kr. adult specimens). 1934. 58 pp., 12 flgs. 1 pi. pp., 24 flgs. Price 9 Danish Icr. 11 . Louis JouBiNf: Les Octopo- des de la croislire du "Dana" 1921-22. 1937. 49 pp., 53 flgs. 1 2 . Hydrographical observations made during the VoL IV (complete): 119 Danish kr. "Dana”-Expedltion 1928-30. 1937. 46 pp.. 18. G. S t ia s n y : Die Scyphomedusen. 1940. 27 p p c Vol n (compieie): 91,50 Danish kr. Price 6.50 Danish kr. 5 flgs. 2 pis. Photographic reprint 1962. P ifo i 8. A nton Fb. Brdhn; Flying-fishes (Exocoetidae) 18. E r n a M o h r : Revision der Centrisddae (Acan- 10 Danish kr. of the Atlantic, systematic and biological stu­ thopterygil Centriscifonnes). 1937. 69 pp., 33 19. Louis F a o e : Mysldacea, Lophogastrida - : dies. 1935. 106 pp., 30 flgs. 7 pis. Pi^ce 17 Da­ flgs. 2 pis. Photographic reprint 1959. Price 1941. 52 pp., 51 flgs. Photographic rqnlcxi nish kr. 25 D ani^ kr. 1962. Price 15 Danish kr.

(continued on back of covea; No. 20. A. Pruvot-Fol: Les Gymnosomes - I. 1942. 40. ViLH. Eoe: Paralepididae I {Paralepis and 69. H. D a m a s : La collection de Pelagosphaera 54 pp., 77 figs. Photographic reprint 1962. Lestidium), 1953. 184 pp., 33 figs. Photographic “Dana”. 1962. 22 pp., 11 figs. Price 6 Danisli Price 15 Danish kr. reprint 1963. Price 55 Danish kr. 60. A lfred W. Ebeling and W a l t e r H. W e e d I 21. A n t o n Fr. B r u u n : A study of a collection of Melamphaidae III. Systematics and distrit the fish Schindleria from South Pacific waters. tion of the species in the bathypelagic fish 1 1940. 12 pp., 8 figs. Photographic reprint V ol. V I I I (complete): 126 Danish kr. nus Scopelogadus V a i l l a n t . 1963. 58 pp., 23 ii 1959. Price 5 Danish kr. 41. Marion Grey: The fishes of the genus Te- Price 17 Danish kr. 22. P. Jespersen: Indo-Paciflc leptocephalids of tragonarus Risso. 1955. 75 pp., 16 figs. and 61. Ole Munk: The eyes of some the genus Anguilla. 1942. 128 pp., 83 figs. charts. Out of print. ceratioid fishes. 1964. 16 pp., 4 pis. Price 24 Danish kr. 42. E, B e r t e l s e n and N. B. M arshall: The 3 figs., 1 pi. 28. Louis Fage: Mysidacea, Lophogastrida - II. Miripinnati, a new order of teleost fishes. 1956. 62. E. B ertelsen and O le Munk: Price 1942. 67 pp., 42 figs. Photographic reprint 34 pp., 15 flgs. and 1 pi. Out of print. Rectal light organs in the ar­ 11 Danish : 1962. Price 20 Danish kr. 48. ViLH, Ege: Paralepididae II (Macroparalepis). gentinoid fishes Opisihoproc- 24. Anton Fr. Bruun: The biology of Spirula 1957. 101 pp., 24 flgs. Out of print. tus and Winteria, 1964. 21 pp., spirula (L.). 1943. 46 pp., 13 figs. 2 pis. Photo­ 44. JoN L. H e r r i n g : The marine water-striders 11 figs., 2 pis, graphic reprint 1961. Price 15 Danish kr. of the **Dana”-Expeditions (Insecta: Hemi- 68. P. L. K ra m p : The Hydromedusae of the Pad 26. Folkb. L i n d e r : Nebaliopsis typica G. O. Sars. ptera). 1958. 14 pp., 6 figs. Price 2 Danish kr. and Indian Oceans. 1965. 162 pp., 13 figs. Fr 1943. 38 pp., 17 figs. 1 pi. Photographic reprint 46. E. B ertelsen: The argentinoid fish Xenoph- 48 Danish kr, 1962. Price 10 Danish kr. talmichihys danae, 1958. 11 pp., 6 figs. and 64. Umberto d’AnconaI and G e m in ia n o Ca 26. A. V e d e l TA-Ning: List of supplementary pela­ 1 pi. Price 2 Danish kr, n a t o : The fishes of the family Bregmacei gic stations in the Pacific Ocean and the At­ 46. P. L. K ra m p : The Hydromedusae of the At­ tidae. 1965. 92 pp., 58 figs. Price 27 Danish ! lantic. 1944. 15 pp., 2 figs. Out of print. lantic Ocean and adjacent waters. 1959. 284 pp., 335 figs, and 2 pis. Price 60 Danish kr. Vol. V (complete): 155 Danish kr. 47. Vilh. Ege: Omosudis G u n t h e r , bathypelagic Vol. XII (complete): 145 Danish kr. genus of fish. 1958. 19pp,, 3 figs. Out of print. 27. Hermann Einarsson : Euphausiacea. I. North­ 65. E r i k M. P o u l s e n : Ostracoda-Myodocopa. Pj ern Atlantic species. 1945. 185 pp., 84 figs. II. Cypridiniformes-Rutidermatidae. Sarsie Photographic reprint 1961. Price 55 Danish kr. Vol. IX (complete): 135 Danish kr. dae and Asteropidae. 1965. 484 pp., 156 fi 28. J. J. T e s c h : The thecosomatous pteropods. I. Price 145 Danish kr. The Atlantic, 1946. 82 pp., 34 figs. 8 pis. 48. Marie-Louise Bauchot: Etude des larves Photographic reprint 1961. Price 30 Danish kr, leptoc^phales du groupe Leptocephalus lanceo- 29. G r a c e E. P i c k f o r d : Vampyroieuthis infernalis loius S tr 5 m m a n et identification k la famille C h u n , An archaic dibranchiate cephalopod, des Serrivomeridae. 1959. 148 pp., 105 figs. 2 VoL XIII (complete): 192 Danish kr. pis. Price 40 Danish kr, I, Natural history and distribution, 1946, 66. C ly d e F. E. R o p e r: A study of the gen 40 pp., 8 figs. Photographic reprint 1961, 49. Klaus Gunther und K urt Deckert: Mor­ Enoploteuthis (Cephalopoda: Oegopsida) in t Price 12 Danish kr. phologic und Funktion des Kiefer- und Kiemen- Atlantic Ocean with a redescription of the ty apparates von Tiefseefischen der Gattungen 30. J. J. T e s c h : The thecosomatous pteropods. species, E. leptara (L each, 1817), 1966. 46 p II, The Indo-Paciflc. 1948, 45 pp., 34 figs. Malacosteus und Phoiostomias (Teleostei, Iso- 24 figs. Price 16 Danish kr, spondyli, Stomiatoidea, Malacosteidae), 1959. 3 pis. Photographic reprint 1961. Price 13 67. PouL H e e g a a rd : Larvae of decapod Crustac< 54 pp., 33 flgs. Price 15 Danish kr. Danish kr. The oceanic penaeids Solenocera - Cerataspii 81. ViLH. E g e: Chauliodus Schn., bathypelagic 60. W alter M, Matsumoto: Descriptions of Eu- Cerataspides. 1966. 147 pp., 345 figs. Price genus of fishes. A systematic, phylogenetic and thynnus and Auxis larvae from the Paciflc and Danish kr. Atlantic Oceans and adjacent seas. 1959. 34 pp., geographical study. 1948. 148 pp., 9 figs. 2 pis. 68. N. B. M a r s h a ll: Baihyprion 31 figs. Price 10 Danish kr. Photographic reprint 1962. Price 45 Danish kr. danae, A new genus and species 5 1 . A. E, P a r r : The fishes of the family Searsidae, of alepocephaliform fishes. 1960. 109 pp., 73 figs. Price 30 Danish kr. Vol. VI (complete): 126 Danish kr. 1966. 10 pp., 3 figs. 52. Louis F a g e : Oxycephalidae. Amphipodes p61a- Price 82. G r a c e E. P i c k f o r d : Vampyroieuihu infernalis 69. N. B. M a rs h a ll and A .V e d e l giques. 1960.145 pp., 79 figs. Price 40 Danish kr. 6 Danish C h u n . An archaic dibranchiate cephalopod. TANiNGf: The bathypelagic IL External anatomy. 1949. 132 pp., 75 figs. macrourid fish, Macroaroides on 9 pis, and in the text. Photographic reprint Vol. X (complete): 147 Danish kr. iiiflaticeps Sm ith and R a d - 1961. Price 40 Danish kr. 53. Elizabeth C. A lexander : A contribution to CLiFFE. 1966. 7 pp., 1 fig., 1 pL 88. SvEN Thore: Investigations on the “Dana'* the life history, biology and geographical di­ 70. O le M unk: Ocular anatomy of some deep s Octopoda. I. Bolitaenidae, Amphitretidae, Vi- stribution of the bonefish. Albala vulpes (L in ­ teleosts. 1966. 63 pp., 28 flgs. 16 pis. Price treledonellidae 4nd Alloposidae. 1949. 85 pp., n a e u s ) . 1961. 51 pp., 16 figs. Price 15 Danish kr. Danish kr. 69 figs. Photographic reprint 1962. Price 54. Vagn Kr. Hansen and K arl Georg Wing- 71. Stanley H. Weitzman: The osteology a 25 Danish kr. s t r a n d : Further studies on the non-nucleated relationships of the Astronesthidae, a fam 84. J. J. T esch: Heteropoda, 1949. 54 pp., 44 figs. erythrocytes of Maurolicus mulleri, and com­ of oceanic flshes, 1967. 54 pp., 31 flgs. Pr and 5 pis. Photographic reprint 1961. Price 20 Danish kr. 15 Danish kr. parisons with the blood cells of related fishes. 1960. 21 pp., 3 pis. Price 5 Danish kr. 72. P. L. K ram p : The Hydromedusae of the Paci 85. A. Fraser-Brunner; Studies in plectognath 56. W alter M. Matsumoto : Identification of larvae and Indian Oceans. Sections II and IIL 19( fishes, I. 1950. 8 pp., 5 figs. Photographic re­ 200 pp., 367 flgs. Price 70 Danish kr. print 1962. Price 4 Danish kr. of four species of tuna from the Indo Pacific Region I. 1962.16 pp., 5 figs. Price 4 Danish kr. 86. J. J, T e sc h : The Gymnosomata II. 1950. 55 pp., 37 figs. Photographic reprint 1962. 66. Sanford A. Moss: Melamphaidae II. A new Price 15 Danish kr. melamphaid genus, Sio, with a redescription VoL XIV (not yet complete); of Sio nordenskjoldii (Lonnberg). 1962. 10 pp., 87. F. B e r n a r d : Decapoda Eryonidae (Eryoneiciis 78. Basil G. N afpaktitis : Taxonomy and distrit et Willemoesia), 1953. 93 pp., 36 figs. Price 4 figs. Price 3 Danish kr. tion of the lantemfishes, genera Lobianchia a 17 Danish kr. 67. E r i k M. P o u l s e n : Ostracoda-Myodocopa. DiaphuSy in the North Atlantic. 1968, 131 p Part L Cypridiniformes-Gypridinidae. 1962. 88. Dan Laursen: The genus lanthina, A mono­ 69 figs. 2 pis. Price 50 Danish kr. 414 pp., 181 figs. Price 120 Danish kr. graph. 1953. 40 pp., 41 figs. and 1 pi. Out 74. C h a n g -Tai S h ih : The systematics and biolo of print. of the family Phronimidae (Crustacea: Amp] VoL XI (complete): 159 Danish kr. poda). 1969.100 pp., 22 figs. Price 40 Danish ] Vol. VII (complete): 135 Danish kr. 58. A lfred W. Ebeling: Melamphaidae I. Syste- 75. E r i k M. P o u l s e n : Ostracoda-Myodocopa. Pi 89. E. Bertelsen: The ceratioid fishes. 1951. matics and zoogeography of the species in the III A. Halocypriformes-Thaumatocypridae a 276 pp., 141 figs. and 1 pi. Photographic bathypelagic fish genus Melamphaes G u n t h e r . Halocypridae. 1969. 100 pp., 40 figs. Price reprint 1961. Price 80 Danish kr. 1962. 164 pp., 73 figs. Price 50 Danish kr. Danish kr.

The reports are being published with irregular intervals. On sale and exchange, see page 2 of cover.