AMERICAN MUSEUM NOVITATES Published by Number 1266 the AMERICAN MUSEUM of NATURAL HISTORY December 10, 1944 New York City

AMERICAN MUSEUM NOVITATES Published by Number 1266 THE AMERICAN MUSEUM OF NATURAL HISTORY December 10, 1944 New York City

MARINE TURBELLARIA FROM THE ATLANTIC COAST OF NORTH AMERICA BY LIBBIE H. HYMAN

Accumulated material of marine flat- not preserve), apparently cellular, although worms from our Atlantic coast, chiefly the cell walls are distinguishable with difficulty coast of Maine and Newfoundland, has from the striated appearance common to furnished the occasion for this paper. The acoel epidermis. As is usual among the larger marine Turbellaria of our Atlantic Acoela, the epidermis is divided by an ap- coast are probably now fairly well known, parently fibrous membrane into a narrow but very much remains to be done on the border containing the basal bodies of the small and minute forms. cilia and a broader inner stratum containing the nuclei (fig. 2). Rhabdites seen in ORDER ACOELA living worm, but not apparent on sections. Epidermis contains clear spaces, somewhat FAMILY PROPORIDAE more nuimerous anteriorly, continuity of AFRONTA, NEW GENUS these spaces with clear channels in mesen- DEFINITION: Proporidae without frontal chyme plainly seen (fig. 2). These channels pore or cluster of frontal glands and with- seem to lead to the mesenchymal vacuoles. out accessory female parts; mouth behind No epidermal gland cells found. No cluster middle, pharynx short; single genital pore, of frontal glands or frontal pore present. male, at rear end; penis simple, without Whether isolated frontal glands exist or papilla. not could not be determined with certainty. TYPE: Afronta aurantiaca. A few bluish masses (haematoxylin stain) occur behind the brain that might be fron- Afronta aurantiaca, new species tal glands, but they did not show any definite structure and could not be traced to the Figures 1-3 anterior end. Epidermis lacks basement MATERIAL: One specimen, sectioned. membrane; is bounded from mesenchyme FORM: Cylindroid, rounded at both by definite muscle layer of outer circular ends, 2 mm. long (fig. 1). and inner longitudinal fibers (figs. 2 and 3). COLOR: Orange yellow, whitish at ends, Mesenchyme has usual appearance-a dorsal surface with short elongated clumps granular vacuolated syncytium (fig. 3); of brownish granules. large spaces occur around penis, smaller EYES: Lacking. but still conspicuous ones in the peripheral GENERAL STRUCTURE: Although the mesenchyme, and quite small spaces in the fixation (hot Flemming's strong solution) is central mesenchyme. Numerous nuclei excellent, the plane of the sections is unfor- in the peripheral, few in the central, mesen- tunate, being obliquely horizontal, slanting chyme. Parenchymal muscle fibers pres- from left to right so that on any section, ent, forming a lattice of longitudinal and right-hand structures are more dorsal transverse fibers (fig. 3). than left-hand ones. Further, a piece has or less been sliced off the posterior dorsal region, Brain well developed (fig. 3), more apparently in trimming the block. These quadripartite, sending two main bundles circumstances have detracted from a and some smaller ones forward, and two proper study of the specimen. main bundles together with many other Epidermis completely ciliated (cilia did fibers backward. Statocyst present in 2 AMERICAN MUSEUM NOVITATES [No. 1266 posterior dorsal part of brain, fusiform, di- plump, ends narrowed, posterior end ter- vided into three compartments, of which minates in adhesive disk, less than 1 mm. central one contains the statolith (fig. 3). long (figs. 4-7). Mouth well behind middle (fig. 3), leads COLOR: White; interior yellow during into short pharynx that is simply inturned sexual maturity. epidermis, not differentiated in any way. EYES: Lacking. REPRODUCTIVE SYSTEM: Simple; gon- GENERAL STRUCTURE: Four specimens ads consist of paired strands of gameto- were sectioned, and although the sec- gonia, testes lateral and dorsal to ovaries. tions are fairly good, some details No accessory female parts found. Indefi- could not be determined. Body is com- nite sperm ducts lead to cap-like seminal pletely ciliated according to Dr. Rein- vesicle closely applied over anterior sur- hard's observations on living specimens; face of penis (fig. 3). Penis consists of cilia were lacking on preserved animals. rounded mass at posterior end of worm; Body lacks typical epidermis; is clothed non-muscular but contains many nuclei. with a narrow, apparently structureless Long narrow lumen opens internally into membrane (fig. 8) of firm, elastic nature, seminal vesicle, externally by male gono- thrown into folds wherever contraction pore at posterior end of worm (fig. 3); occurs. Presumably epidermis is, there- lumen lined by hardened material; no fore, of the "insunk" type, common among penis papilla seen. Sperm appear to be of Acoela, in which the nuclei are sunk into short thick shape. the mesenchyme. No trace of frontal LOCALITY: Mt. Desert Island, Maine, glands. Anterior tip contains elongated dredged in surface mud at a depth of 30 eosinophilous structures, probably rham- feet, near the Mt. Desert Island Biological mites (fig. 8); no rhabdites found. Rear Laboratory, August 16, 1937. end forms circular adhesive disk covered TYPE: One set of serial sections (one with adhesive papillae (fig. 8), to which slide) deposited in A.M.N.H., Cat. No. could be traced eosinophilous strands in 339. underlying mesenchyme, presumably out- REMARKS: This is the specimen men- lets of eosinophilous gland cells, but not tioned in my 1938 report as a species of clearly distinct from muscle fibers, also Plagiostomum. Sections showed the animal eosinophilous. Epidermal membrane has to be an acoel, not an alloeocoel. A new sharp inner boundary, just inside which is genus appeared to be necessitated by the subepidermal musculature, chiefly of longi- lack of frontal glands, lack of differentiated tudinal fibers; circular fibers were not pharynx, and simple tubular penis without definitely seen. Longitudinal muscle layer papilla. gradually increases in thickness towards posterior elid and is well developed in con- ECTOCOTYLIDAE, NEW FAMILY nection with adhesive disk. DEFINITION: Acoela of ectocommensal Mesenchyme consists of loose granular habits, with tubular plicate pharynx, and material, containing scattered nuclei, more caudal adhesive disk. abundant ventrally. No mesenchymal muscle fibers seen. ECTOCOTYLA, NEW GENUS Well-developed brain present just an- DEFINITION: Ectocotylidae with armed terior to pharynx; consists of oval mass, penis, seminal bursa with one nozzle, and granular in center, encircled by nerve cells two genital pores. (fig. 8); no definite nerve strands seen. TYPE: Ectocotyla paguri. Statocyst embedded in anterior surface of brain. Ectocotyla paguri, new species PHARYNX: Is unique among the Acoela Figures 4-8 in being of the plicate, protrusible type, MATERIAL: Number of specimens sent similar to that of planarians. When pro- by Dr. E. G. Reinhard. truded was seen to be (covered with cilia- FORM: Fusiform, curved, middle part and to be armed with a;7few spines (fig. 4), 1944] TURBELLARIA FROM THE ATLANTIC COAST 3 according to observations of Dr. Reinhard LOCALITY: Biological station of the on living specimens; spines were not seen University of Maine, Ellsworth, Maine, in sections. Pharynx lies in pharyngeal epizoic on Pagurus pubescens, collected cavity opening by mouth anterior to middle August, 1940, by Dr. E. G. Reinhard. of body (fig. 8), shortly behind brain. COTYPES: Several specimens mounted Pharyngeal cavity and outer and inner sur- whole (one slide) and set of sections (one faces of pharynx lined by same structureless slide), A.M.N.H., Cat. Nos. 340, 341. membrane as general body surface. Under REMARKS: This animal is remarkable in epidermis, thin layer of longitudinal muscle several ways: in the possession of a plicate fibers; interior of pharynx consists of pharynx, hitherto unknown among the mesenchyme with nuclei, concentrated near Acoela, in the presence of a caudal adhesive the surfaces; along center of mesenchyme disk, also not previously found in the eosinophilous strands occur, probably order, and in its ectccommensal habits. pharyngeal glands, seeming to open at dis- This appears to be the first ectocommensal tal end of pharynx. Pharynx leads di- acoel found, although 'several entocommen- rectly into mesenchyme. sals are known, inhabiting the interior of REPRODUCTIVE SYSTEM: What were pre- echinoderms. sumed to be testes consist of several compact groups of spermatogonia in latero- ORDER ALLOEOCOELA ventral regions (fig. 8). No ovaries or FAMILY PLAGIOSTOMIDAE ovogonia were found but all specimens contain in ventral part of plump central body Plagiostomum album Hyman, 1938 region, round deeply staining masses, each Figures 9-11 lodged in a mesenchymal compartment MATERIAL: Several specimens collected bounded by fibers. These masses appear to in tidal zone on shores of Mt. Desert Island, be syncytia, composed of areas with small Maine. nuclei and other areas of larger nuclei. It FORM: Plump, cylindroid, to 4 mm. long is presumed that these masses are embryos (fig. 9), anterior end slightly narrowed, and hence that the animal is viviparous. blunt, posterior end forming a little tail Separate male and female gonopores pres- or at times or in larger specimens rounded ent. Male gonopore in front of stalk-like or indented. posterior end; leads into tubular cavity COLOR: White with a black spot be- whose inner end contains the penis. Penis tween, and in front of, the eyes and a deli- consists of oval thick-walled sac armed cate lacing of brown lines over the dorsal with curved, hook-like stylet. No seminal surface. vesicle or channels leading to the penis Ems: Four, in a trapezoid arrangement were found but' behind the penis is some (fig. 9). eosinophilous material, probably glands GENERAL STRUCTURE: My own serial associated with the male system. Female sections have been supplemented by others gonopore shortly anterior to male gono- kindly lent by Dr. Ulric Dahlgren. Body pore (fig. 8). Leads into rounded cavity clothed in a ciliated epidermis, of low with muscular wall in which is lodged the columnar form, taller at the two ends, es-' seminal bursa, a rounded mass with mus- pecially the posterior end, than elsewhere.. cular wall, provided with one nozzle Whether the epidermis is cellular or not (mouthpiece). Exact relation of bursa to could not be determined. It contained no its cavity could not be determined-bursa special structures. Definite basement probably attached to wall of cavity by the membrane present underlain by usual sub- nozzle. epidermal muscle layer of outer circuirl HABITS: Ectocommensal on the surface and inner longitudinal fibers; diagonal of the hermit crab, Pagurus pubescens. Ac- fibers appeared to be absent. Muscle tive, lively, moving rapidly about in meas- layer gradually increases in thickness to- uring-worm fashion (fig. 7), alternately wards posterior end. No frontal pore or attaching anterior end and adhesive disk. cluster of frontal glands present; some 4 AMERICAN MUSEUM NOVITATES [No. 1266 large cyanophilous gland cells occur in the this has lumen in less mature specimen sides of the anterior end. Mesenchyme (fig. 10), but is filled with prisms of secre- compact; parenchymal muscle fibers are tion in mature specimen (fig. 11). Pro- present in fair numbers. The material static vesicle is covered with thick layer of was not favorable for a detailed study of prostatic glands. Distal end of prostatic the nervous or excretory systems. No vesicle narrows, curves posteriorly, enters indications of the latter system were found. proximal end of long canal-like penis bulb DIGESTIVE SYSTEM: Subterminal mouth containing the introverted penis papilla. opens into wide pharyngeal cavity, con- Wall of penis bulb consists of epithelium taining free distal end of very large underlain by muscle layer of inner circular pharynx, which in life equals about one- and outer longitudinal fibers. Penis pa- fourth the body in length. Pharynx of pilla very long and slender composed of two variabilis textus type, in which outer mus- epithelia with strong longitudinal muscle cular wall consists of outer circular and in- fibers between. Mass of unicellular glands ner longitudinal fibers, while inner muscle embraces base of penis papilla and enters layer next the lumen is reversed with outer with longitudinal muscle fibers. Base of longitudinal and inner circular fibers (fig. penis papilla continuous with conical pro- 10). Strong radial fibers course between tuberance, usually termed penis sheath, inner and outer walls of pharynx. Powerful that projects posteriorly into proximal end sphincter muscle occurs near distal end of of genital antrum. Penis sheath has con- pharynx. Well-developed nervous stratum struction similar to wall of penis bulb and is situated to inner side of outer muscle of antrum and receives some unicellular layers, but no definite nerve ring noticed. glands. Genital antrum consists of wid- Pharynx leads by brief narrowed esophagus ened anterior part that bears penis sheath into sacciform intestine, which has peculi- at its proximal end and receives oviduct arity of extending forward around proximal into dorsal wall; and of narrowed distal end of pharynx (fig. 9). Intestine consists part that leads to common genital pore at of thick, highly vacuolated, apparently rear end of body. This narrowed part re- syncytial epithelium underlain by a deli- ceives on each side bundle of long-necked cate layer of circular muscle fibers. unicellular glands, and from its proximal REPRODUCTIVE SYSTEM: Testes are a end there projects ventrally a rounded, pair of elongated masses in lateral body re- thick-walled blind sac of unknown pur- gions to either side of the rear part of the pose. This sac seems to contain in its pharynx and anterior part of the intestine. anterior wall some glandular masses, but Ovaries are a pair of rounded bodies pos- this could not be determined precisely. terior to the testes. No ducts were found Wall of antrum consists of epithelium, then leading from the gonads to the copulatory circular, then longitudinal muscle fibers; apparatus, except that the distal end of the its narrowed distal part and also the lining common ovovitelline duct was seen entering of the blind sac are ciliated. the roof of the male antrum in the sagittal DIFFERENTIAL DIAGNOSIS: P. album series of sections (fig. 10). Sagittal section differs from other members of the genus in of copulatory apparatus shown in figure 10; the combination of long pharynx, forward frontal view of apparatus from more ma- projection of intestine around inner end of ture specimen cut horizontally, from sec- pharynx, very elongated form of penis tions lent by Dr. Dahlgren, shown in figure bulb, penis papilla, and common antrum, 11. In the latter series the common ovo- and blind ventral sac of antrum. P. album vitelline duct could not be found. This considerably resembles both in external duct constitutes the entire female part of characters and details of the copulatory the apparatus. Male apparatus compli- apparatus the common European fresh- cated, beginning with elongated seminal water P. lemani. vesicle placed longitudinally and ventrally. LOCALITY: Mt. Desert Island, Maine, Posterior end of this curves and enters pyri- under stones in the tidal zone. form prostatic vesicle, directed forward; TYPE: One set of sagittal serial sections 1944] TURBELLARIA FROM THE ATLANTIC COAST 5

(one slide) deposited in A.M.N.H., Cat. Wheatlandii from the Massachusetts coast, No. 338. and I have compared them with the New- foundland specimens that I consider to be ORDER TRICLADIDA P. littoralis ( = ulvae). I am not able to see SUBORDER MARICOLA any difference between these forms, except that the Massachusetts specimens are FAMILY PROCERODIDAE smaller than the Newfoundland ones and Subfamily Procerodinae that they have a smaller copulatory bursa. These are not adequate grounds for a GENUS PROCERODES GIRARD, 1850 specific distinction. I am, therefore, of the Procerodes littoralis (Strom), 1768 opinion that the Massachusetts form called since Wilhelmi's monograph Procerodes Syn.: Hirudo littoralis Strbm, 1768. Planaria littoralis 0. F. Mtller, 1776. Wheatlandii is conspecific with the Euro- Planaria ulvae Oersted, 1843. pean P. littoralis ( = ulvae) or at best is but Procerode8 Wheatlandii Girard, 1850. a geographic race or variety of the latter. Planaria frequen8 Leidy, 1855. The smaller size of the Massachusetts Procerode8 ulvae Verrill, 1893. specimens may be merely of ecolo- A number of specimens which I assign gical nature, an illustration of the general to this species were presented to me by rule that animals increase in size towards Dr. A. S. Pearse who collected them at the poles. Brigus, Newfoundland, August 16, 1938. There is scarcely any species of turbellarian Procerodes Warrenii (Girard), 1850 regarding which there has been more taxo- Syn.: Vortex Warrenii Girard, 1850. nomic confusion than this one. Wilhelmi Fovia Warrenii Girard, 1852. (1909) in his monograph failed to clear up A yellowish gray marine triclad with the confusion, and it has remained for truncate anterior end devoid of auricles Bock (1926) to settle the matter finally. is common along the shores of Mt. Desert Further synonymy will be found in these Island, Maine, under rocks in the tide zone. two references, together with a discussion It appears probable to me that this is Pro- of the taxonomic history of the form. I cerodes Warrenii, although certain identi- accept the conclusion of Bock that Plan- fication was impossible as no sexual speci- aria littoralis and Procerodes ulvae are iden- mens were found. This species appears to tical, and that the valid name is Procerodes be seldom taken in the sexual state. What littoralis (Strom). This species then evi- is known about it is given in Wilhelmi's dently occurs along the northern shore monograph (1909). of the North Atlantic from Newfoundland to Scandinavia. It remains for me to con- GENUS FOVIELLA BOCK, 1925 sider whether Procerodes Wheatlandii 1843 is conspecific with Procerodes littoralis Foviella affinis (Oersted), Syn.: Planaria affinis Oersted, 1843. (= ulvae). Wilhelmi (1907, 1909) main- Fovia affinis Stimpson, 1857. tains that they are not but gives no grounds Fovia affrinis Jensen, 1878. for this opinion except that he has studied Planaria littorali8 Van Beneden, 1860. material from their respective localities. Fovia affinis Jensen, 1878. Comparison of his figures of the entire A number of specimens which I assign animal (1909, pl. 1, figs. 17 and 19) and to this species were collected by Dr. A. S. of the sagittal section of the copulatory Pearse at Brigus, Newfoundland, August apparatus (1909, pl. 15, fig. 13, and pl. 16, 1938, and turned over to me. The 16, fig. 9) clearly shows that there is no dif- taxonomic history of this species is also ference between his P. ulvae and P. very complicated and has been reviewed Wheatlandii except the larger size of the by Bock, 1925, who has given a good de- copulatory bursa in the former. I, too, scription of the species for which he created have studied alive and as whole mounts the name Foviella. I found no differences and serial sections specimens of Procerodes between my specimens and Bock's de- 6 AMERICAN MUSEUM NOVITATES [No. 1266 scription. This species, like Procerodes chamber. Oviduct leaves postero-lateral littoralis, therefore, ranges along the North surface of each ovary, proceeds posteriorly Atlantic coast from Scandinavia to New- lateral to ventral nerve cord, at level of foundland. genital antrum curves inward and dorsally and, accompanied by eosinophilous glands, PROBURSIDAE, NEW FAMILY enters the bursal canal on that side about DEFINITION: Maricola with copulatory where bursal canal joins genital antrum. Large copulatory bursa of irregular rounded bursa anterior to the penis bulb and with posterior ovaries, situated at the level of form lies anterior to penis bulb as in fresh- the posterior end of the pharynx. water triclads; bursal canal leaves center of posterior surface of bursa; is very narrow at first, proceeds posteriorly above PROBURSA, NEW GENUS penis and, widening gradually, curves ven- DEFINITION: With the characters of the trally, receiving the two oviducts separately family. on each side, and enters common antrum. TYPE: Probursa veneris. Penis consists of large, very muscular bulb placed immediately behind copulatory Probursa veneris, new species bursa and elongated penis papilla. Bulbar lumen is lined by wavy glandular epithe- Figures 12, 13 lium. Common gonopore occurs below MATERIAL: Several whole mounts and penis papilla. Glands open on ventral sur- sets of serial sections presented by Dr. face behind gonopore. Sagittal view of Marvin Meyer. copulatory complex shown in figure 13. FORM: Preserved specimens of elon- LOCALITY: Fire Island, which is a sand gated oval shape (fig. 12), presumably bar on the Atlantic Ocean side of Long more elongated and slender in life, to 3 Island, New York, near the western end of mm. long; auricles not evident on whole the latter. Habitually found in empty mounts but stated by Dr. Meyer to be shells of the clam Venus, whence the specific present. name. Collected September 4, 1940, by COLOR: Brownish black, flecked and Dr. Marvin Meyer. streaked. TYPE: One whole mount, deposited in EYES: Usual two, somewhat back from A.M.N.H., Cat. No. 328; cotype, one set anterior end as usual in Maricola. of serial sections (four slides), A.M.N.H., GENERAL STRUCTURE: A few points Cat. Nos. 329-332. may be mentioned. Digestive tract sends REMARKS: This triclad has two remark- median branch forward in front of eyes able features in which it differs from all (fig. 12); posterior rami of digestive tract known Maricola: the posterior position are confluent at posterior end. Ventral of the ovaries and the location of the copu- nerve cords have strong cross connection latory bursa anterior to the penis bulb. below the penis bulb; they are also con- Although some Maricola are known in fluent at the posterior end. which the copulatory bursa curves forward REPRODUCTIVE SYSTEM: Large testes, so as to lie above the penis papilla, none is about seven to nine on each side, occur as known in which the bursa is situated an- usual between bases of digestive branches terior to the penis bulb except the pres- (fig. 12); they fill space from ventral nerve ent species. This location of the bursa is cords to dorsal epidermis. First pair is identical with the location characteristic close behind eyes; last pair about level of of fresh-water triclads. Throughout the copulatory bursa (fig. 12). Sperm ducts triclads the ovaries are situated anteriorly, form spermiducal vesicles ventral to copu- shortly behind the eyes, and although they latory bursa, unite to common sperm duct may be somewhat more posterior than this that enters middle of penis bulb. Ovaries in some Maricola, in no other known tri- are a pair of rounded bodies to either side clad do they occur so far posteriorly as in at level of posterior end of pharyngeal Probursa veneris. 1944] TURBELLARIA FROM THE ATLANTIC COAST 7

ORDER POLYCLADIDA ducal vesicles, packed with sperm. These SUBORDER ACOTYLEA turn anteriorly about level of middle of prostatic vesicle and, running ventral to SECTION CRASPEDOMMATA this vesicle, enter separately the posterior FAMILY CRYPTOCELIDAE angles of the seminal vesicle. Latter is muscular, thick-walled, arched body, curv- COMPROSTATUM, NEW GENUS ing dorsally, then bending posteriorly, and DEFINITION: Cryptocelidae with tentac- by narrowed connection entering anterior ular and cerebral eye clusters, anteriorly end of large, elongated prostatic vesicle. located pharynx, interpolated prostatic Prostatic vesicle has thick muscular wall, vesicle, and large Lang's vesicle. is lined by tall, wavy, glandular epithelium, TYPE: Comprostatum insularis. from which come blobs of secretion filling the lumen. Posterior end of prostatic Comprostatum insularis, new species vesicle narrows, passes directly into large, Figures 14-16 elongated penis papilla, which may be bent MATERIAL: Several preserved and live forward in some specimens. Penis papilla specimens sent by Dr. H. Humm. has muscular outer and inner walls of outer FORM: Slender, elongate, sides parallel, longitudinal and inner circular muscle both ends rounded (fig. 14), to 40 mm. long fibers. Penis papilla lies in male antrum, in life, about six times as long as wide. opening below by male gonopore by way of COLOR: White with pink tinge, may narrowed channel. have pink spots; pink color probably re- Female gonopore, well separated from sult of ingested food. male gonopore, leads into forward-slanting EYES: Marginal band of very small eyes, passage having strong sphincter muscle fades out posteriorly, so that posterior end (fig. 16). This opens proximally into ex- lacks marginal eyes (fig. 14). Tentacular panded thin-walled vagina which makes an eye clusters occur behind level of the brain, S-curve posteriorly and dorsally, becoming consist of four or five to about eight eyes, very thick walled with less wide lumen. depending on size of specimen. Brain has Vagina then curves posteriorly, and after exceedingly large "granule masses." Cere- receiving in its ventral wall the common bral eyes consist of elongated group on each oviduct it narrows to form the stalk of side, beginning behind the brain and ex- Lang's vesicle. This stalk after a short tending forward above brain and granule posterior course enters the very large and masses as a few widely spaced eyes to a level elongated Lang's vesicle. The vagina ap- less than halfway the distance to the anterior pears to be ciliated throughout. margin (fig. 15). There are no frontal eyes LOCALITY: Key Largo, Florida, under as in other cryptocelids. rocks in shallow water, fairly common, DIGESTIVE SYSTEM: Short, ruffled, probably generally distributed throughout rounded, or oval pharynx occurs well an- the Florida keys, collected in 1940 by Mr. terior to the middle. From it main in- Harold Humm; live specimens were sent testine extends forward to brain giving in two shipments in January, 1944. off numerous lateral branches (fig. 14). TYPE: One whole mount, A.M.N.H., In some specimens, main intestine also Cat. No. 333; sexual region of the same extends short distance behind pharynx; removed and sectioned, four slides, A.M. in other specimens this was lacking. N.H., Cat. Nos. 334-337. COPULATORY APPARATUS: Male apparatus, directed backward, lies about SECTION SCHEMATOMMATA middle of body, some little distance behind the pharynx (fig. 14). Female apparatus FAMILY HOPLOPLANIDAE behind male apparatus; separate gonopores. Sperm ducts become visible along- Hoploplana inquilina (Wheeler), 1894 side pharynx; proceed posteriorly, widen- In my article on the Atlantic coast poly- ing into irregular, very thin-walled spermi- clads of the United States, 1940, I left open 8 AMERICAN MUSEUM NOVITATES [No. 1266 the question whether this species occurs, as data confirm the claim of Pearse that claimed by Pearse, 1938, in two forms, the a smaller form of this species exists along larger nominal form found on the Massa- the more southern part of our Atlantic chusetts coast commensal with the snail coast. Schechter found H. inquilina in the Busycon, and a smaller form, thaisana, snail Thais floridana haysae Clench in found southward, commensal in the snail Barataria Bay, Louisiana. These speci- Thais. Additional information on this mens are much larger than any previous question has been furnished by Dr. Leslie specimens recorded, measuring up to 8 by 5 Stauber, 1941, and Dr. Victor Schechter, mm. The variety of Thais is also larger 1943, both of whom have kindly sent speci- than Thais floridana floridana in which mens. Stauber reports the finding of Pearse found his specimens of Hoploplana considerable numbers of H. inquilina in the "thaisana." The present indications, there- snail Urosalpinx cinerea Say in Delaware fore, are that there is but one form of Hop- Bay. They were not found in Busycon in loplana inquilina upon our coast and that this locality. The largest of Stauber's its size varies with the size of the host and specimens measure 5 by 3 mm., and most probably other environmental circum- range from 1-3 mm. Hence, Stauber's stances.

SUMMARY 1. Two new acoels, one new alloecoel, toralis (Strom), 1768 (= Procerodes ulvae), one new marine triclad, and one new poly- and Foviella affinis (Oersted), 1925, are clad are described from the Atlantic coast reported from Brigus, Newfoundland; of North America. hence these species are distributed in the 2. The acoels are Afronta aurantiaca, North Atlantic from Newfoundland to family Proporidae, and Ectocotyla paguri, Scandinavia. Procerodes Wheatlandii Gi- new family Ectocotylidae, both from the rard, 1850, found on the Massachusetts Mt. Desert Island region, Maine. The coast, is considered to be at best a geo- former lacks frontal glands and accessory graphic variant of P. littoralis. female structures. The latter is one of the 5. A new marine triclad, Probursa ven- most remarkable acoels yet discovered, eris, new family Probursidae, shores of having a protrusible plicate pharynx and Long Island, New York, differs from all caudal adhesive disk provided with adhe- known triclads in the far posterior position sive papillae; it also appears to be vivipa- of the ovaries and differs from all other rous. It is epizoic on the hermit crab marine triclads in having the copulatory Pagurus pubescens. bursa situated anterior to the penis bulb. 3. Plagiostomum album, also from the 6. A new polyclad, Comprostatum insu- Mt. Desert Island region, is described. laris, family Cryptocelidae, is described 4. The marine triclads Procerodes lit- from the Florida keys.

LITERATURE References prior to 1909 will be found in Wil- Proc. U. S. Natl. Mus., vol. 89, pp. helmi, 1909. 449-495. BOCK, SIXTEN PEARSE, A. S. 1925. Oersteds Planaria affinis wiederent- 1938. Polyclads of the east coast of North deckt. Zool. Anz., vol. 64, pp. 149-164. America. Proc. U. S. Natl. Mus., 1926. 0. F. MtXllers Planaria littoralis end- vol. 86, pp. 67-98. lich identifiziert. Ibid., vol. 67, pp. SCHECHTER, VICTOR 195-206. 1943. Two flatworms from the oyster-dwell- HYMAN, LIBBIE H. ing snail Thais floridana haysae 1938. Faunal notes. Bull. Mt. Desert Island Clench. Jour. Parasitol., vol. 29, p. Biol. Lab., for 1937, 1938, pp. 24-25. 362. 1940. The polyclad flatworms of the Atlantic STAUBER, LESLIE A. coast of the United States and Canada. 1941. The polyclad Hoploplana inquilina 1944] TURBELLARIA FROM THE ATLANTIC COAST 9

thaisana Pearse 1938 from the mantle WILHELMI, J. cavity of oyster drills. Jour. Parasitol., 1909. Tricladen. Fauna und Flora des vol. 27, pp. 541-542. Golfes von Neapel, Monogr. no. 32, 403 pp.

FOR ALL FIGURES

1, epidermis; 2, brain; 3, statocyst; 4, line duct; 30, male antrum; 31, common gono- testes; 5, ovaries; 6, mouth; 7, seminal ves- pore; 32, prostatic glands; 33, penis glands; icle; 8, penis; 9, male gonopore; 10, basal 34, blind sac; 35, common antrum; 36, copu- bodies of cilia; 11, epidermal nucleus; 12, latory bursa; 37, bursal canal; 38, common mesenchymal nuclei; 13, channels; 14, ad- sperm duct; 39, bulbar lumen; 40 cere- hesive disk; 15, rhammites; 16, pharynx; bral eyes; 41, tentacular eyes; 42, marginal 17, pharyngeal cavity; 18, embryos; 19, eyes; 43, main intestine; 44, sperm ducts; seminal bursa; 20, female gonopore; 21, penis 45, Lang's vesicle; 46, penis papilla; 47, stylet; 22, adhesive papillae; 23, eyes; 24, vagina; 48, common oviduct; 49 stalk of intestine; 25, sphincter; 26, prostatic vesicle; Lang's vesicle; 50, penis papilla; 51, granule 27, penis bulb; 28, penis sheath; 29, ovovitel- mass. 10 AMERICAN MUSEUM NOVITATES [No. 1266

Fig.1.."Afrontaauataa96~~~~~~~~~~~~~~~~~~~~~~~~~f e NI. 6~~~~~~~~~~~~~~~~~~ If

Fig.1.Afront auatic, rm ie

Fig. 2. Anterior epidermis of Afronta aurantiaca, showing epidermal channels continuous with mesenchymal spaces. Fig. 3. Frontal section of Afronta aurantiaca, showing general structure and reproductive system 19441 TURBELLARIA FROM THE ATLANTIC COAST 11

67 ~~~~~~~~~~~22 Fig. 4. Side view of Ectocotyla paguri, showing general shape and extended pharynx, sketched from life by Dr. E. Reinhard. Figs. 5-7. Sketches of living specimens of Ectocotyla paguri made by Dr. Reinhard: 5, dorsal view; 6, lateral view; 7, worm in act of crawling. Fig. 8. Sagittal section of Ectocotyla paguri, showing general structure plicate pharynx, reproductive system, and embryos. 12 AMERICAN MUSEUM NOVITATES [No. 1266

10 Fig. 9. Plagiostomum album, from life. Fig. 10. Sagittal section of Plagiostomum album, showing general structure. 19441 TURBELLARIA FROM THE ATLANTIC COAST 13

Fig. 11. Frontal view of copulatory apparatus of Plagiostomum album, from sections courtesy of Dr. Ulric Dahlgren. Fig. 12. Probursa veneris, from whole mount, courtesy of Dr. Marvin Meyer, showing general structure. 14 AMERICAN MUSEUM NOVITA TES [No. 1266

Fig. 13. Sagittal view of the copulatory apparatus of Probursa veneris. Fig. 14. Comprostatum insularis, from whole mount. 1944] TURBELLARIA FROM THE ATLANTIC COAST 15

. .

0*C I.. 414r 15

Fig. 15. Eye arrangement of Comprostatum insularis. Fig. 16. Sagittal view of the copulatory apparatus of Comprostatum veneris.