7

PREFACE

The first International Symposium on the Biology papers were read by title and are included either in of the Seal was held at the University of Guelph, On­ full or abstract form in this volume. The 139 particip­ tario, Canada from 13 to 17 August 1972. The sym­ ants represented 16 countries, permitting scientific posium developed from discussions originating in Dub­ interchange of a truly international nature. lin in 1969 at the meeting of the Marine In his opening address, V. B. Scheffer suggested that Committee of the International Council for the Ex­ a dream was becoming a reality with a meeting of ploration of the Sea (ICES). The culmination of such a large group of biologists. This he felt three years’ organization resulted in the first interna­ was very relevant at a time when the relationship of tional meeting, and this volume. The president of ICES marine mammals and man was being closely examined Professor W. Cieglewicz, offered admirable support as on biological, political and ethical grounds. well as honouring the participants by attending the The scientific session commenced with a seven paper symposium. section on evolution chaired by E. D. Mitchell which The programme committee was composed of experts showed the origins and subsequent development of representing the major international sponsors. W. N. this amphibious group of higher vertebrates. Many of Bonner, Head, Seals Research Division, Institute for the arguments for particular evolutionary trends are Marine Environmental Research (IMER), represented speculative in nature and different interpretations can ICES; A. W. Mansfield, Director, Arctic Biological be attached to the same fossil material. Readers of this Station, Fisheries Research Board of Canada (FRB) volume should be aware of such differences when read­ represented the International Commission for North­ ing the papers in this section. The twelve papers of west Atlantic Fisheries (ICNAF); and K. S. Norris, S. H. Ridgway’s section on functional anatomy illus­ Director, Marine Council Executive Com­ trated the fundamental structure of the seal, as well mittee, represented the International Biological Pro­ as its associated control mechanisms. R. J. Schusterman gram (IBP). The Food and Agriculture Organization followed this theme by introducing ten papers on be­ of the United Nations (FAO) also offered its support haviour. He established a major focus on social or­ to the programme and ICNAF has contributed to the ganization and communication and their association financing of this volume. with the functional anatomy of the . D. E. Sponsors of national origin were the Fisheries Re­ Sergeant chaired the population dynamics section of search Board of Canada (FRB), the National Re­ seven papers, covering the modelling of populations search Council of Canada (NRCC), the Canadian and method of analysis of seal populations around the National Sportsmen’s Show (CNSS), the World Wild­ world. In the fifth section, J. R. Geraci, by means of life Fund (Canada) (WWF), and the University of papers and a panel discussion dealt with the care and Guelph. management of captive pinnipeds. W. N. Bonner co­ In his preliminary remarks Professor Ronald intro­ ordinated a presentation in the broad area of ecology, duced the representatives of these groups; namely J. R. and was able to bring together studies on environmen­ Weir, Chairman, Fisheries Research Board of Canada; tal factors and their associated behavioural and gene­ S. Bata, International Director and J. S. McCormack, tic control systems. The physiology section was chaired Director, World Wildlife Fund (Canada); and R. T. by H. T. Andersen, his introductory remarks forming D. Birchall, President, Canadian National Sportsmen’s the initial paper of the section. The other six papers Show and a Director of WWF (Canada). of his section emphasized the underwater responses of W. C. Winegard, President of the University of seals. The final and general section, chaired by J. E. Guelph, welcomed participants to the symposium and King, offered a broad coverage of several of the more commented particularly on how pleased he was to interesting areas in various disciplines. welcome representatives from so many countries. Later, A. W. Mansfield acted as rapporteur for the entire at a banquet sponsored by the Department of the En­ programme, and his report stressed the need for con­ vironment, Canada, he offered an invitation to the tinued cooperation by all biologists so that they might group to return in 1975 for a Second International understand seals and their importance to environmen­ Seal Symposium. tal studies. Altogether 62 papers were presented. A further 14 This volume includes with one exception, those pa- 8 K. Ronald pers either presented, read by title, or abstracted, but mammals of the world’ by D. W. Rice and V. B. the continuing discussion on the biology of the seals Scheffer (U.S. Fish and Wildlife Service, Washing­ led to one further paper that is included here. Some ton, 1968) has been used as the standard reference on of the discussion was formal and, where recordable, is nomenclature. included here, but by far the greater part of discussion The work of the chairmen of each of the seven sec­ was informal and hence must remain as extremely tions of this volume is especially recognized. As well, valuable, but merely mental recollections of the par­ the convenor wishes to thank the programme com­ ticipants in the symposium. mittee for their ability to support a somewhat unortho­ The symposium achieved its purpose of bringing dox procedural system, and particularly the sponsors together scientists interested in the Pinnipedia and it ICES, ICNAF, IBP, CNSS, FRB, NRCC, WWF (Ca­ offered leads into the international examination of nada), FAO, and the University of Guelph for their marine mammals. valuable financial assistance. The editors with little apology recognized that they The convenor is most grateful to Mr. H. Tambs- have not reached a completely uniform format in this Lyche, General Secretary of ICES, for his advice and volume since they have allowed use of both English encouragement from the embryonic stages of the sym­ and metric systems of measurement and both English posium to the publication of the proceedings; he also and North American word usage for the sake of har­ recognizes the considerable amount of expert help pro­ mony. The main editorial structure has been the con­ vided by A. W. Mansfield in co-editing this volume. sistency of usage throughout a particular paper. Finally, the effort put into both the symposium and Attempts have also been made to attain a fairly this volume by Mrs. Ginny Bandesen has been beyond uniform for the species, but where there has measure, but I hope that she will accept the results of been any doubt caution has not overridden clarity. As the symposium recorded here as tangible proof of her in other mammalian groups, the systematics of the most valuable contribution. To the members of the Pinnipedia are still open to much interpretation. The Dean of the College of Biological Science’s office, the references are cited according to an Annotated Biblio- university support staff and our host Dr. W. C. Wine- praphy on the Pinnipedia*. The ‘List of the marine gard, I express on behalf of the participants and my­ self, our sincerest thanks. * Ronald, K., L. M. Hanly and P. J. Healey, College of Bio­ K. Ronald, logical Science, University of Guelph, Ontario, Canada. Convenor

The following have kindly acted as Discussion Care and Management Section Leaders of the different Sections and also assisted in J. R. Geraci the editing of the contributions: Department of Zoology, University of Guelph, Guelph, Ontario, Canada. Evolution Section Ecology Section E. D. Mitchell Arctic Biological Station, Fisheries Research Board W. N. Bonner of Canada, Ste. Anne de Bellevue, Quebec, Canada. Seals Research Division IMER, c/o Fisheries Labora­ tories, Lowestoft, Suffolk, England.

Functional Anatomy Section Physiology Section S. H. Ridgway H. T. Andersen School of Anatomy, University of Cambridge, Nutrition Institute, University of Oslo, Blindern, Cambridge, England. Oslo, Norway.

Behaviour Section General Session R. J. Schusterman J . E. King Department of Psychology, California State University Department of Zoology, University of New South Hayward, California 94542, U.S.A. Wales, Kensington, N.S.W., Australia.

Population Dynamics Section Summary D. E. Sergeant A. W. Mansfield (Rapporteur) Arctic Biological Station, Fisheries Research Board of Arctic Biological Station, Fisheries Research Board Canada, Ste. Anne de Bellevue, Quebec, Canada. of Canada, Ste. Anne de Bellevue, Quebec, Canada. 544

Rapp. P.-v. Réun. Cons. int. Explor. Mer, 169: 544-549. 1975.

SPECIFIC ANTIQUITY OF THE SUCKING LICE AND EVOLUTION OF OTARIID SEALS1

K . C. K im The Frost Entomological Museum, Department of Entomology, The Pennsylvania State University, University Park, Pennsylvania 16802, USA

C. A. R e p e n n i n g United States Geological Survey, Menlo Park, California 94025, USA and

G. V. M o r e j o h n Moss Landing Marine Laboratories, Moss Landing, California 95039, USA

INTRODUCTION of these marine carnivores. Thus a relatively few fos­ In the Symposium on the Biology of the Seal a sig­ sils reveal the phylogenetic history. nificant correlation was recognized among the conclu­ In this discussion we are concerned only with the sions of the three papers which we presented. These last 5 or 6 million years of otariid evolution. Records papers discussed evolution of the otariid seals based now available suggest that the sea lions (Subfamily upon the fossil record (Repenning, 1975), an inter­ Otariinae) evolved from the more primitive fur seals pretation of possible phylogenetic sequence of the (Subfamily Arctocephalinae) possibly as long ago as otariids based upon the bacula of the living forms 3 million years. This suggesdon is based on an arbitrary (Morejohn, 1975), and the ecology and morphological definition of the fur seals and the earliest records of adaption of the sucking lice on the northern living taxa of sea lions. (Kim, 1975). In the last paper those lice endemic to The more primitive otariids, whose history dates back the living genera of otariid seals were listed, and their at least 12 and possibly 15 million years, are all small host specificity was discussed. The conclusions of the forms in comparison with living sea lions. They have three papers were mutually corroborative, and pro­ skeletal limb proportions more comparable to living vided further evidence for evolution of otariid seals. fur seals, and they have double-routed cheek teeth. At the same time the known chronology of the fossil These conditions lead to the assumption that they are record of otariid seals provides rather compelling sug­ best considered primitive fur seals rather than sea lions. gestion of the antiquity of the -seal association. In addition, the fur seals are presumed to be the more Here, the conclusions of the three papers are colla­ primitive otariids because abundant underfur obvious­ borated and synthesized to document this greater un­ ly has insulating advantages in water only to moderate derstanding of the evolution of the otariid seals and of depths where hydrostatic pressure would not greatly their sucking-louse fauna. The significance of the host compress the air it traps. Thus, thick underfur is found specificity and diversity of the sucking lice (Echinoph- in many shallow-water mammals, in the Rodentia as thiriidae, Anoplura) on the Pinnipedia is emphasized. well as in the . Among marine mammals, that feed in deep-water under great hydrostatic pres­ sure, the value of underfur is lost because of the com­ pression of the trapped air, and conservation of body THE FOSSIL RECORD heat must depend on relatively imcompressible sub­ The phylogenetic history of the otariid seals is bet­ cutaneous adipose tissue. A thick envelope of subcu­ ter documented by the fossil record, than it is for many taneous fat covers the body of all living marine mam­ other mammalian groups. This does not result from a mals except Enhydra which feeds only in shallow great abundance of fossil material but rather from the water. conservative nature of the evolutionary diversifications Although most living otariids have at least some single-rooted cheek teeth, the tendency toward single 1 Authorized for publication as Paper No. 4310, Journal Series of the Pennsylvania Agricultural Experiment Station, Univer­ (or fused) roots is much stronger in living sea lions sity Park, Pa. 16802. than in living fur seals. The earliest otariid fossils with Specific antiquity of the sucking lice and evolution of otariid seals 545

single-rooted cheek teeth are between 3 and 4 million bacular apices are parallel-sided in most individuals. years old, based upon the approximate correlation with However, a growth series of Eumetopias bacula shows zebrine horses found elsewhere in the same stratigraphie that it develops first from an or Zalo- unit (Burleson, 1948; Allison in Leffler, 1964). Fossil phus-like condition, and with continued lateral swell- otariids with all cheek teeth bearing two roots are known ing, passes through a transversely broadened condition in deposits 4 to 5 million years old based upon associated like that of the bacula of Otaria and , and pliohippine horses (L. G. Barnes, personal commun­ later as a subadult, through the adult condition of ication). Remains of living genera of sea lions are Phocarctos. Finally, with full maturity, Eumetopias known in the North Pacific Basin in deposits possibly develops an essentially circular outline when viewed 2 million years old. It is thus presumed that the sea in anterior aspect. lions may have diverged from the ancestral fur seals It seems possible, therefore, that the baculum of about 3 million years ago. Arctocephalus as a fur seal and the baculum of Zalo­ The earliest records of living genera of sea lions in phus as a are the most primitive of those the Southern Hemisphere are less than one million found in the living otariids. In fact, the cheek teeth years old. However, because they are generically dist­ and skulls of some species of Arctocephalus are strik­ inct from the sea lions of the Northern Hemisphere ingly similar to (Repenning, Peterson, and and because living genera are known to have lived Hubbs, 1971). In addition, Zalophus californianus and between 1 and 2 million years ago to the north, it is Arctocephalus pusillus have bred in captivity and presumed that the sea lions dispersed to the Southern produced several intergeneric offspring (Mohr, 1952). Hemisphere perhaps 2 million years ago and there Zalophus, in several respects, could be considered a evolved into the living taxa. fur seal without fur and may be of the living genera, In addition, the three southern sea lion genera, Phoc- the form closest to the archetypal sea lion. Stirling arctos, Neophoca and Otaria, harbor the same sucking and Warneke (1971) cite a number of lines of evidence louse, microchir (Troussart and Neu­ which suggest that Arctocephalus pusillus is more like mann), as do the two northern genera, Eumetopias a sea lion than a fur seal, despite the presence of and Zalophus. This fact requires the interpretation underfur. that the southern sea lions did not evolve separately The developmental stages of the bacular apex of from some fur seal in the Southern Hemisphere, rather Callorhinus are similar to Arctocephalus and Zalo­ a common origin of all sea lion genera is indicated, phus as subadults and adults. However, the adult presumably in the North Pacific Basin. bacular apex of Callorhinus, resembles a “figure eight” in terminal view. The ventral knob is consider­ THE BACULUM ably expanded laterally and the dorsal knob less so. A marked waist between dorsal and ventral knobs is The present fossil record helps little in learning the obvious. Thus, Callorhinus has a bacular form un­ events involved in the development of the two living known in other otariids either as adults or in their genera of fur seals, Arctocephalus and Callorhinus. growth series and appears to represent a specialized Some aspects of fossil fur seals 7 to 9 million years offshoot of the Arctocephaline stem. Other traits not old suggest relationship to Callorhinus and others to shared by the other otariids also suggest this: 1) milk Arctocephalus; there are no known fossils which are teeth begin to be shed while still in utero (Scheffer clearly ancestral to only one of the living genera. and Kraus, 1964) ; 2) lactation time is shortened to However, consideration of the bacula of living otariids about 4 months (Peterson, 1968); 3) cartilaginous and and of one fossil otariid, provides some evidence of skin extensions of flippers are markedly greater than probable evolutionary patterns. in all other otariids; 4) the species undergoes the most The bacula of living otariids possess, at maturity, extensive annual pelagic migrations (Kenyon and Wil­ both dorsal and ventral knobs on the apex and have kie, 1953); and 5) the species has a male to female a shaft that varies from round, through oval, to tri­ size disparity of 4-5 to 1 (Scheffer, 1958), probably angular in cross section. The apex is transversely greater than in any other otariid. broader in most of the living sea lions than in the fur One fossil baculum is known from an otariid of seals, and this condition is most accentuated in the roughly 8 million years ago, and this most resembles sea lion genera Phocarctos and Eumetopias. The sea that of Callorhinus. The suggestion is, therefore, that lion, Zalophus, and the fur seal, Arctocephalus, have the lineage leading to Callorhinus diverged from the bacula essentially identical in apex morphology, al­ stem lineage earlier than did the sea lion, while the though that of Zalophus is usually stouter and broad­ main branch of otariid evolution proceeded from the er. Both dorsal and ventral knobs are of approx­ Arctocephalus condition to further modification of the imately equal width and, when viewed anteriorly, the bacular apex.

35 546 K. C. Kim, C. A. Repenning and G. V. Morejohn

With the later divergence from this lineage, broad­ zumpti (Werneck) on Arctocephalus pusillus. Echin- ening of the apex developed in the sea lions and has ophthirius is monotypic and exclusively parasitic upon progressed to the most advanced condition seen in the Phocidae; E. horridus (von Olfers) is known from Phocarctos and Eumetopias. The primitive pattern of Cystophora cristata, Erignathus barbatus, Halichoerus the bacular apex, the retention of underfur and of grypus, Pagophilus groenlandicus, vitulina, primitive limb proportions, and the reduced rate of hispida, and Pusa sibirica. The fourth genus, Lepid- development of single-rooted cheek teeth apparently ophthirus, is comprised of two species: L. macrorhini has remained constant in Arctocephalus since this Enderlein is found only on Mirounga leonina and L. divergence of the sea lions from the stem lineage of piriformis Blagoveschensky on Monachus manachus. the otariids occurred. Unlike other pinnipeds, the , Cal­ lorhinus ursinus, hosts two species of sucking lice; Antarctophthirus callorhini (Osborn) inhabiting the THE SUCKING LICE naked skin and Proechinophthirus fluctus (Ferris) in The sucking lice of the family are the fur or underfur habitat (Kim, 1971 ; 1972). The se­ obligate, permanent ectoparasites exclusively on the cond species of Proechinophthirus, P. zumpti Werneck, aquatic carnivora mainly Pinnipedia. They are fierce is found on Arctocephalus pusillus and presumed to blood suckers, and their entire life cycle is completed inhabit the underfur, but no species of Antarctophthi­ on the host. The lice are host-specific, and inhabit rus is yet known from the southern fur seal. the skin and the pelage of pinnipeds. Thus, survival Antarctophthirus microchir (Troussait and Neu­ of the echinophthiriids depends solely upon the sur­ mann) is the sole species known from the living sea vival of the host and upon the microenviron­ lions, including all genera of both northern and south­ ment their host provides. ern hemispheres; Eumetopias, Zalophus, Otaria, and The pinniped-infesting sucking lice are so highly Phocarctos (Ferris, 1951) as well as Neophoca (B. J. specialized that their affinity is quite obscure. The fact Marlow, personal communication). A. microchir in­ that they have unique morphological traits and host habits the naked parts of the skin, namely flippers, specificity to the pinnipeds suggests that the echin­ of these living sea lions. This species is not found on ophthiriids must have evolved with the pinnipeds since other pinniped hosts. the ancestral seals ventured into marine life. Unquest­ Proechinophthirus is closely related to Echinophthi- ionably, this specialization that obscures taxonomic rius in several morphological traits: 1) no abdominal relationships is the result of adaption to the marine scales: 2) antenae four-segmented; 3) pseudopenis of environment by the Echinophthiriidae, as the sucking the male round without distinct apical process; and lice in general are essentially terrestrial ectoparasites. 4) abdomen elongated; however, Proechinophthirus However, fissiped carnivores are usually infested with differs from Echinophthirius in morphological details biting lice (Mallophaga) but not with sucking lice. of the fore legs and chaetotaxy. All legs of Echinoph­ The single exception is in the Ganidae, on which two thirius are similar in shape and size and their claws species of sucking lice are known. These belong to the are blunt, and the setae on the body and head are genus Linognathus, which is specific to the Bovidae short. Lepidophthirus is a highly specialized taxon and the Cervidae (Artiodactyla), and the acquisition among the known echinophthiriids, and differs from of Linognathus by canids is therefore recent. others in having a short abdomen with a dense cover The echinophthiriid lice are unique in that the of scales, a pseudopenis that is disconnected at the body is more or less thickly beset with various setae, apex, and claws of the middle and hind legs that are some of which are modified as scales ; the thoracic and pointed. Antarctophthirus, on the other hand, shares abdominal spiracles are of distinctive type with a some morphological similarities to Proechinophthirus long, more or less membranous atrium and a highly and somewhat to Lepidophthirus ; it has an elongate specialized closing apparatus; the fore legs are usually abdomen which is, in contrast to Proechinophthirus, small and slender, with an acuminate claw; the middle covered with scales and has different setae, the pseudo­ and hind legs have very stout tibiotarsi, and the ab­ penis is complete but has a short apical process, the domen is completely membranous. antennae are four-segmented in nymphs but are five- The Echinophthiriidae includes four distinct genera segmented in the adult, and claws of the middle and at present (Table 131). Antarctophthirus is the most hind legs are blunt. diverse taxon and includes six known species from a wide range of hosts; Otariidae, , and the EVOLUTION OF OTARIID SEALS AND THEIR LICE . Proechinophthirus is found exclusively on the Arctocephalinae and includes two known spe­ The fossil records suggest that the sea lions dispersed cies, P. fluctus (Ferris) on Callorhinus ursinus and P. to the southern hemisphere perhaps 2 million years Specific antiquity of the sucking lice and evolution of otariid seals 547

Table 131. List of known species of Anoplura from Pinnipedia

The Sucking Lice (Family Echinophthiriidae) Host (Order Pinnipedia)

Antarctophthirus Proechinophthirus Echinophthirius lepidophthirus Family Otariidae Subfamily Arctocephalinae A. catlorhini P. fluctus Callorhinus ursinus ??? P. zumpti Arctocephalus pusillus A. microchir Subfamily Otariinae Eumetopias jubata Phocarctos hookeri Otaria bryonia Zalophus californianus Neophoca cinerea Family Odobenidae A. trichechi Odobenus rosmarus Family Phocidae Subfamily Monachinae L. piriformis Monachus monachus L. macrorhini Mirounga leonina A. ogmorhini Hydrurga leptonyx » Leptonychotes weddelli A . lobodontis Lobodon carcinophagus A . mawsoni Ommatophoca rossi Subfamily E . horridus Cystophora cristata Erignathus barbatus Halichoerus grypus Pagophilus groenlandicus Phoca vitulina Pusa hispida Pusa sibirica

ago, and there evolved into the three southern genera the two fur seals have evolved along separate lineages of living sea lions, while the two northern sea lion much more ancient than the sea lion lineage; a sug­ genera evolved in the northern hemisphere. Both gestion already indicated by the study of their bacula. northern and southern sea lions harbor a single poly­ It is presumed, but not yet established, that other typic species of louse, Antarctophthirus microchir. species of Arctocephalus harbor Proechinophthirus. This fact suggests that A. microchir has existed on Occasional contact is known between most species, the the sea lion for more than 2 million years, since the most remote possibility being that of Arctocephalus time when this mammal became a distinct evolution­ townsendi, from Mexican and southern California wa­ ary lineage and prior to dispersal of this lineage to ters, having contact with other species south of the the southern hemisphere between 1 and 2 million years Equator. Callorhinus currently breeds on San Miguel ago. The evolution of this lineage of the sucking lice Island, California, and A. townsendi now visits the was exceedingly slow relative to that of the sea lions. island as a wanderer. Remains of both genera are The presence of Proechinophthirus as a unique pa­ abundant in Indian garbage dumps on the island and, rasite on both Callorhinus ursinus of the northern he­ to judge by the number of young individuals, it seems misphere and on Arctocephalus pusillus of the south­ possible that both fur seal genera bred there. A. town­ ern hemisphere suggests that this lineage is of as great an sendi, therefore, may well have a Callorhinus-like antiquity as is the fur seal lineage. Proechinophthirus louse fauna rather than one typical of other species is definitely the most generalized taxon showing many of the genus. primitive morphological traits, and may be considered Antarctophthirus is a typical echinophthiriid and to be closer to the ancestral echinophthiriid, a condi­ adapted to the microhabitat (naked skin) which is tion quite comparable to that already indicated for directly influenced by the thermoregulatory activities their host, the fur seals. If the rate of evolution of of the host and by numerous factors of the marine Proechinophthirus has been comparable to that of environment. From morphological and ecological evi­ Antarctophthirus, the fact that two species have evol­ dence it may be concluded that Antarctophthirus, ved, P. fluctus endemic on Callorhinus and P. zumpti prosessing a broad genetic adaptability, established on Arctocephalus pusillus, would certainly suggest that itself on all pinnipeds not host to Echinophthirius and

35» 548 K. C. Kim, C. A. Repenning and G. V. Morejohn

Endemie Lice Boculu m

E X PL A NATION

Ac - A col torhin i Am -A. microchir Pi- P. fluctus Pz- P. zum pti P - Proechinophthirus ^"v/(First smgle- y rooted cheek A - Antorctophthirus V teeth)

Uj Baculum Apex Form □ Ô ø 8 0.0 a Û, 0 8 Û 0 E C^sO Fossil Records

NORTH PACIFIC SOUTH PACIFIC Kim, Repenning, Morejohn, 1972

Figure 385. Phylogeny of the Otariidae inferred from the fossil record, form of the baculum, and endemic sucking lice.

Lepidophthirus with the single exception of Arcto­ 2 million years, and strongly suggests a monophyletic cephalus pusillus. However, it is suspected that Ant- origin of the sea lions out of an ancestral fur seal. arctophthirus will eventually be found on the southern The most probable evolutionary history, in the opinion fur seal (Table 131). O f six known species, A. cal- of the authors, is shown as a phylogenetic diagram in lorhini is the most generalized species of Antarctoph­ Figure 385. thirus. The lack of scales on the thoracic sternum in A. callorhini is definitely an indication of primitiveness. REFERENCES This fact seems to support the conclusions derived Burleson, G. L. 1948. A Pliocene pinniped from the San Diego from the fossil record and the bacular anatomy that Formation of southern California. Univ. Calif., Publ. Zool., the ancestral otariids were fur seal-like . This 47:247-55. Ferris, G. F. 1951. The sucking lice. Pac. Coast Entomol. Soc. should be further substantiated by studying the louse Mem., 1:1-320. fauna of Arctocephalus. Kenyon, K. W. & Wilkie, F. 1953. Migration of the northern fur The possible origin of A. callorhini on Callorhinus is seal, Callorhinus ursinus. J. Mammal., 34:86-98. not clearly answerable at this time. This may be a K im , K . C. 1971. The sucking lice (Anoplura: Echinophthiriidae) of the northern fur seal, descriptions and morphological adap­ relic from the louse fauna inhabiting the ancestral tation. Entomol. Soc. Am., Ann., 64:280-92. otariids, now extinct, which still retains some primitive Kim, K. C. 1972. Louse populations of the northern fur seal morphological traits, as does its host. (Callorhinus ursinus). Am. J. Vet. Res., 33:2027-36. Most significantly, the presence of A. microchir as Kim, K. C. 1975. Ecology and morphological adaptation of the sucking lice (Anoplura: Echinophthiriidae) on the northern an inhabitant of both the northern and southern tæxa fur seal. In this volume, pp. 504-15. of sea lions (Otariinae) suggests that a monospecific Leffler, S. R. 1964. Fossil mammals from the Elk River formation, lineage of the sucking lice has existed for at least Cape Blanco, Oregon. J. Mammal., 45:53-61. Specific antiquity of the sucking lice and evolution of otariid seals 549

Mohr, E. 1952. Die Robben der Europäischen Gewässer. Vol. 12: Repenning, C. A., Peterson, R. S., Hubbs, C. L. 1971. Contri­ 207. In Monographien der Wildsäugetiere. Paul Schöps, butions to the systematics of the southern fur seals, with parti­ Frankfurt am Main. cular reference to the Juan Fernandez and Guadalupe species, Morejohn, G. V. 1975. A phytogeny of the otariid seals based pp. 1-34. In Antarctic Pinnipedia. Ed. by W. H. Burt. Antarct. upon the morphology of the baculum. In this volume, pp. Res. Ser., 18. Am. Geophys. Union, 226 pp. 49-56. Scheffer, V. B. 1958. Seals, sea lions, and . A review of Peterson, R. S. 1968. Social behavior in pinnipeds with parti­ the Pinnipedia. Stanford Univ. Press, Stanford Calif. 179 pp. cular reference to the northern fur seal. pp. 3-53. In The Stirling, I. & Warneke, R. M. 1971. Implications of a comparison behavior and physiology of pinnipeds. Ed. by R. J. Harrison, of the airborne vocalizations and some aspects of the behavior R. G. Hubbard, R. S. Peterson, and R.J. Schusterman. of the two Australian fur seals species (Arctocephalus sp.) on the Appleton-Century-Crofts, New York. 411 pp. evolution and present taxonomy of the genus. Aust. J. Zool., Repenning, C. A. 1975. Otariid evolution. In this volume, pp. 19:227-41. 27-33.