Vol. V October, 1932 No. 2c. BULLETIN OF The New York State College of Forestry At Syracuse University Hugh P. Baker, Dean Roosevelt Wild Life Annals VOLUME 3 NUMBER 2 OF THE Roosevelt Wild Life Forest Experiment Station PARASITES OF ONEIDA LAKE FISHES Part 2. Descriptions of New Species and some general taxonomic considerations, especially concerning the Trematode Family Heterophyidae Trichodina renicola (Mueller, 1931), a ciliate parasite of the urinary tract of Esox niger CONTENTS OF RECENT ROOSEVELT WILD LIFE BULLETINS (To obtain these publications see announcement on back of title page) Roosevelt Wild Life Bulletin, Vol. 2, No. 1. October, 1923. 1. The Control of Blood-sucking Leeches, with an Account of the Leeches of Palisades Interstate Park Dr. J. Percy Moore. 2. Preliminary Report on the Parasitic Worms of Oneida Lake, New York. Dr. Henry S. Pratt. 3. Acanthocephala from the Fi.shcs of Oneida Lake, New York. Dr. Harley J. Van Cleave. 4. Current Station Notes The Director and Editor. Roosevelt Wild Life Bulletin, Vol. 2, No. 2. February, 1924. I. The Ecology of the Plankton Algae in the Palisades Interstate Park, Including the Relation of Control Methods to Eish Culture Dr. Gilbert M. Smith. Roosevelt Wild Life Bulletin, Vol. 2, No. 3. March, 1924. 1. The Status of Fish Culture in Our Inland Pulilic W aters, and the Role of Investi- gation in the Maintenance of Fish Resources Dr. William C. Kendall. 2. Current Station Notes The Director and Editor. Roosevelt Wild Life Bulletin, Vol. 2, No. 4. February, 1925. 1. The Relation of Wild Life to the Public in National and State Parks. Dr. Cliarlcs C. Adams. 2. The Big Game Animals of Yellowstone National Park Edmund Heller. 3. The Food of Trout in Yellowstone National Park Dr. Richard A. Muttkowski. 4. Current Station Notes The Director and Editor. Roosevelt Wild Life Bulletin, Vol. 3, No. 1. February, 1925. 1. The Birds of the Yellowstone National Park Milton P. Skinner. 2. Current Station Notes The Director and Editor. Roosevelt Wild Life Bulletin, Vol. 3, No. 2. March, 1925. 1. The Muskrat in New York: Its Natural History and Economics, Dr. Charles E. Johnson. 2. Current Station Notes The Director and Editor. Roosevelt Wild Life Bulletin, Vol. 3, No. 3. September, 1926. 1. The Summer Birds of Central New York Marthes Aretas A. Saunders. 2. Additional Notes on the Summer Birds of Allegany State Park. Aretas A. Saunders. 3. Current Station Notes The Director and Editor. Roosevelt Wild Life Bulletin, Vol. 3, No. 4. October, 1926. 1. The Economic and Social Importance of Animals in Forestry, with Special Refer- ence to Wild Life Charles C. Adams. 2. The Land — Economic Survey in Michigan R. A. Smith. 3. Current Station Notes Charles C. Adams. Vol. V OCTOBI-.R. 193 2 No. 2c. BULLETIN OF The New York State College of Forestry At Syracuse University Hugh P. Baker, Dean Roosevelt Wild Life Annals VOLUME 3 NUMBER 2 OF THE Roosevelt Wild Life Forest Experiment Station Entered as second-class matter October 18, 1927, at the Post Office at Syracuse, N. Y., under the Act of August 24, 1912 ANNOUNCEMENT The serial publications of the Roosevelt Wild Life Forest Experiment Station consist of the following- : 1. Roosevelt Wild Life Bulletin, 2. Roosevelt Wild Life Annals. The Bulletin is intended to include papers of general and popular interest on the various phases of forest wild life, and the Annals those of a more technical nature or having a less widesjiread interest. The editions of these pul)lications are limited and do not permit of general free distribution. Exchanges are invited. The subscription price of the Bulletin is $4.00 per volume of four numbers, or $1.00 per single munber. The price of the Annals is $5.00 per volume of four numbers, or $1.25 per single number. All communications concerning pul)lications should be addressed to The Director and Editor, Roosevelt Wild Life Forest Experiment Station, Syracuse, New York. Copyright, 1932, by Roosevelt Wild Life Forest Experiment Station [74] TRUSTEES OF THE NEW YORK STATE COLLEGE OF FORESTRY Ex Officio Dr. Charles W. Flint, Chaiucllur Syracuse University Dr. Frank P. Grave.s, Commissioner of Education Albany, N. Y. Hon. Henry Morgenthau, Jr., Conservation Commissioner Albany, N. Y. Hon. Hekuek'i H. Lehman, Lieutenant-Governor Albany, N. Y. Appointed uv the (joveknor Hon. Harold D. Cornwali Utica, N. Y. Hon. George VV. Driscoli Syracuse, N. Y. Hon. William H. Kelley Syracuse, N. Y. Hon. Alfred E. Smith New York City Hon. Edward H. O'Hara Syracuse, N. Y. Hon. Charles A. Upson Lockport, N. Y. Hon. J. Henry Walters New York City Hon. Edmund H. Lewis Syracuse, N. Y. Officer of the Board Hon. Alfred E. Smith President HONORARY ADVISORY COUNCIL OF THE ROOSEVELT WILD LIFE STATION American Members Mrs. CoRiNNE Roosevelt Robinson ' New York City Hon. T heodore Roosevelt New York City Mr. Kermit Roosevelt New York City Dr. George Bird Grinnell New York City Hon. Gifford Pinchot Milford, Pa. Mr. Chauncey J. Hamlin Buffalo, N. Y. Dr. George Shiras, 3rd Washington, D. C. Dr. Frank M. Chapman ; New York City Dean Henry S. Graves New Haven, Conn. European Member Viscount Grey Fallodon, England [75] ROOSEVELT WILD LIFE STATION STAFF Hugh P. Baker, M.F., D.Oec Dean of the College Charles E. Johnson, A.M., Ph.L) WiLFORD A. Dence, B.S Miriam S. Mockford Director of the Station Ichthyologist and Ass't Director Secretary Temporary Appointments * MvRON T. TowNSEND, Ph.D Field Naturalist M. W. Smith, M.A Field Naturalist Justus F. Mueller, Ph.D Field Naturalist Dayton Stoner, Ph.D Field Ornithologist Charles J. Spiker, M.A Field Naturalist LeRoy Stegeman, M.S Field Naturalist H. J. Van Cleave, Ph.D Field Naturalist * Including only those who have made field investigations and whose reports are now in |ireparation. [76] GENERAL CONTENTS PAGE 1. Parasites of Oneida Lake fishes. Part II. Descriptions of new species and some general taxonomic considerations, especially concerning the trema- tode family Heterophyidae. Justus F. Mueller and Harley J. Van Cleave 79 2. Trichodina renicola (Mueller, 1931), a ciliate parasite of the Urinary bladder of Esox Niger 139 ILLUSTRATIONS PLATES Plate 15. Allacanlhochasmus artus new spscies 83 Plate 16. New Allocreadiidae 87 Plate 17. New species of parasites from Umbra limi 93 Plate 18. Daclylogyrus extensus new ?,'pec\cs 97 Plate 19. Bothriocephalus formosus new speciesi 101 Plate 20. Hepaticola bakeri new species 105 Plate 21. Spiniteclus gracilis and Spinitectiis carolini 109 Plate 22. The ansLtomy ol Microphallus ovatus 113 Plate 23. Fish trematodes of the family Heterophyidae 117 Plate 24. Fish trematodes of the family Heterophyidae 123 Plate 25. Chart showing the evolutionary tendencies in the Heterophyidae inhabiting the alimentary canal of hshes 129 Plate 26. Superficial anatomy of Trichodina renicola 150 Plate 27. Detailed anatomy of Trichodina renicola 152 [77] Digitized by the Internet Archive in 2015 https://archive.org/details/rooseveltwildlif03unse_4 PARASITES OF ONEIDA LAKE FISHES PART II. DESCRIPTIONS OF NEW SPECIES AND SOME GENERAL TAXONOMIC CONSIDERATIONS, ESPECI- ALLY CONCERNING THE TREMATODE FAMILY HETEROPHYIDAE. By Justus F. Mueller* and Harley J. Van Cleave f Field Naturalists, Roosevelt Wild Life Station CONTENTS PAGE Introduction 80 Section 1 . Descriptions of new species 84 Allacanthochasntus artus new species 84 Allocreadium halli new species 88 Triganodistommn attenuatum new species 89 Triganodistomum simeri new species 90 Neascus grandis new species 91 Gyrodactylus cylindriformis new species 95 Dactylogyrus extensus new species 98 Bothriocephalus formosus new species 99 Hepaticola bakeri new species 103 Section 2. Redescriptions of two species of the nematode genus Spinitectus. . . 106 Spinitectus gracilis Ward and Magath 107 Spinitectus carolini Holl 110 Section 3. Synopsis of the family Heterophyidae (Trematoda) from fresh- water fishes of North America. . ; 114 Family diagnosis 118 Subfamilies of the Heterophyidae 119 Subfamily Heterophyinae Ciurea, 1924 120 The genus Vietosoma Van Cleave and Mueller, 1932 120 The genus Acetodextra Pearse, 1924 121 The genus Cryptogonimus Osborn, 1903 124 The genus Caecincola Marshall and Gilbert, 1905 125 The genus Centrovarium Stafford, 1904 126 Subfamily Neochasminae Van Cleave and Mueller, 1932 126 The genus Neochasmus Van Cleave and Mueller, 1932 127 The genus AUacanthochasmus Van Cleave, 1922 130 Life cycle 131 Section 4. Family relationships of the genus Microphallus Ward, 1901 132 Literature cited 135 * Assistant Professor of Zoology, New York State College of Forestry, Syracuse, New York. t Professor of Zoology, University of Illinois, Urbana, Illinois. [79] 80 RoosCi'dt Wild Life Aiuials INTRODUCTION I-'our years ago tlic authors undertook an in\cstigation of the parasites of the fishes of Oneida Lake, New York, as a part of the program of the Roose- veh Wild Life Station. It was hoped that an intensive study of parasites in a single lake might yield valuahle information on the numerous and com])licated problems of host-parasite relationships. Before any analysis of our results could be made available and the reciprocal relations of host and parasite could be dis- cussed in terms of ecological and biological relationship, it was necessary to make accurate identifications of extensive collections of parasitic worms. The scattered condition of the literature and the unsatisfactory descriptions available for many of the species have rendered identifications difficult. In spite of the fact that fish parasites have been studied rather intensively on this continent for two genera- tions, we have continued to encounter new species which can be discussed in their relations to the biology of fishes, and the life of the lake as a whole, only after they have been named and described and their ])roper positions in the general scheme of classification have been determined. In Part I of our survey (Van Cleave and Mueller, 1932), we presented descriptions of twelve species of trematodes and three species of nematodes which we considered as new. The si)ecies included in the foregoing article comprised forms encountered in the first two years of our field investigation. Collections taken during tht summer of 1931 have vielded a considerable number of jmrasitic worms not previously found in the lake as well as l)etter specimens of some of the species obtained in previous summers. Among these new records there are included nine new species of parasitic worms for which descriptions are pre- sented for the first time in this ]iaper. The descriptions of species in both Parts I and II are but preliminary to the initial object of the survey, — a final report which will include observations on the biology and ecology of the worm parasites of Oneida Lake fishes. Since the collections herein considered are but continuations and extensions of the field and laboratory studies initiated in Part I of this report, the acknowledgments of personal and professional obligation extended in Part I are implied without repetition. There are four fairly distinct sections of the present paper. In Section 1 are assembled the specific descriptions of nine new species of parasitic worms. These include seven trematodes or flukes, one cestode or tapeworm, and one nematode or roundworm. The following list gives the names of the nine new species here described. New species of flukes or Trematoda Family Heterophyidae AUacanthochasmus arfiis Family Ali^ocreadiidae Allocrcodiuin halli Triganodistomtiui attciiuatitm Trigoiiodistoinuni siiiicri I\irusitcs of Oneida Lake I'islics 81 Family Strkjkidae Ncasciis (jraiidis Fam ily Gyrodactylidak Gyrodactylus cylindrifonnis Dactylogyrus cx tens us New species of tapeworm or Cestoda Family PTYCiioiiOTiiRiiDAE Bothrioccpliahis fonnosiis New species of roundworm or Nematoda Family Trichinellidae H cpaticola bakcri In addition to the descriptions of new species, a number of general taxonomic pro1)lenis are discussed. Two species of nematodes belonging to the genus Spini- tectus, encountered in our survey, fail to agree with the descriptions of known members of the genus 1)ut the points of difference have been determined as result- ing from incomplete and in some extent erroneous descriptions of species. These two species of Spinitectus are here redescribed and accurately differentiated for the first time as Section 2 of this paper. In connection with our extended field study of living worms and laboratory investigation of preserved specimens, we have had unusual opportunity for under- standing the morphology and taxonomy of some of the forms studied, because of the relative abundance and excellent condition of the material at our disposal. Among the trematodes parasitic in fishes, there are several genera which have been the subject of disputed relationships by investigators specializing on the taxonomy of this class. Several of these genera of uncertain family affiliations have been so favoral)ly represented in our collections that we are able to offer conclusive evi- dence of their relationship which align them directly with the family Hetero- phyidae. One section of this paper (Section 3) sets forth the detailed evidence which has led us to place the genera Vietosoma, Acetodextra. Allacanthochasmus, Neochasmus. Caecincola. Cryptogonimus and Centrovarium in the family Hetero- phyidae. At the same time, we have reviewed the old arguments and have amassed new information on the family relationships of members of the genus Microphallus which has frequently been assigned to the Heterophyidae. On the basis of detailed evidences set forth in Section 4 of this paper. Microphallus is excluded from the Heterophyidae and, following the recommendation of Travassos (1920), is recognized as type of the family Microphallidae. In the section which immediately follows, the description of each new species is preceded by a brief statement of its systematic position. 82 Roosevelt Wild Life Annals Plate 15. Allacaitthochasinits artiis new species. Fig. 1 : A young, mature specimen of Allacanthochasinits artus seen from dorsal surface. Fig. 2: An oral spine of A. artus, in lateral view, for comparison with Fig. 3. Stippled portion of spine embedded in oral sucker. Outline of oral sucker stippled. Fig. 3: An oral spine of A. varius from same relative position as spine shown in Fig. 2. Fig. 4: \'entro-genital complex of A. artus, seen in side view. Abbreviations ac — acetatnilitin es — eye spots ex — excretory bladder g— gonotyl gp — genital pore m — metraterm OS — oral sucker ov — ovary ph — pharynx sp — spines sr — seminal receptacle sv — seminal vesicle t — testis ut — uterus vd — vitelline duct vs — vesicula seminalis vt — vitellaria 83 Pr.ATK 15 JFM 84 Rooscrcll Wild Life .■liiiials SECTION 1. DESCRIPTIONS OF NEW SPECIES 'rUKMATODA : FaMILV J 1 KT KR( )l' 1 1 V 1 DAK Tlie s^cmis Allai-anthochasmiis has been the subject of diverse opinions as to its family relationsliip. I'oche (1926) ascribed it to the family Acanthostomidae and in this is followed by Fuhrmann ( 192S). This assignment, as shown in detail in Section ?i of this article, is based upon imjierfect understanding of the geni- talia. According to the i)resent authors (Van Cleave and Mueller, 1931), the genus Allacanthochasmus belongs to the family Heterophyidae. As originally defined, the single species included in the genus Allacantho- chasmus is so highly variable that A. variiis was chosen for its specific name. An extended study of living" and preserved materials from Oneida Lake fishes has given full confirmation of the presence of an additional sjiecies in this genus to which we are attaching the name Allacanthochasmus artiis. Allacanthochasmus artus new species (Figures 1, 2, 4, 55, 56, 63, 67) Host. — Lcpibcma clirysops, in intestine. Throughout the jjrogram of field studies on the fish parasites of Oneida Lake, hoth encysted and free immature specimens of the genus Allacanthochasmus have been encountered frequently in a considerable variety of fish hosts. However, we have never found members of this genus reaching full sexual maturity in Oneida Lake in any host other than the white bass (Lepibema chrysops). During the first two years of our field and laboratory study we felt relatively certain that all of the specimens in our collections represented the highly variable species A. z'uriits. Ultimately, the examination of living worms under high magnification revealed characters readily available for the recognition of two sharply defined grou])s. These characters are so significant that there can be no doubt of the validity of the new species to which we have assigned the name Allacantho- c has III us artus. A review of the approximately two thousand specimens of the genus Allacan- thochasmus, which we have stained and mounted for study, from the extensive col- lections of that genus, reveals the fact that A. artus is much less common than A. varius. The two forms occur in our cf)llections in the ratio of approximately one A. artus to twenty-five A. varius. Reexamination of the original material serving as the basis for the descrip- tion of A. varius, shows that the holotyi)e of that species and the series of paratypes selected to represent it include no individuals of A. artus. However, in the col- lections from Lake Erie, and from Lake Pokegama in Wisconsin, A. artus appears in ap])roximately the same ratio to A. varius as that which we have found in Oneida Lake. Description. — Body elongate, slender, about 1.3 mm. long and from 0.08 mm. to 0.14 mm. in diameter; broadest at the level of the crural fork where the excre- tory bladder (Fig. 1, ex) is greatly dilated. As a consequence of this dilatation of J\ir(isitcs of Oneida Lake I'islws 85 the excretory bladder, the esoi)liaj^us ;in(I crura hang very free in the body and in unobstructed view, even in whole mounts. Oral sucker funnel-shaped, its li|> bearing 26 to 29 prominent cuticular spiiu-s arranged in a single circle. Frequently the lip is reflexed to such an extent that the spines diverge from a ])oint posterior to the oral sucker. These spines ( hig. 2) are distinctly different from tho.se of x i. z'ariiis { l<'ig. ,^ ) , in that the posterior tip of each is bent almost at a right angle with the line of attachment, the recurved portion ])ointing toward the median axis of the worm, (^vary (ov) a pretesticular transverse band with fewer lobes than A. z'aiiiis. Vitellaria lateral to crura from ovary anteriorly to near fork of crura; in anterior region the follicles of the two sides become continuous over the dorsal surface of the body. Uterus (ttt) a single sling in the posterior third of the body, with a descending and an ascending stem winding loosely. Eggs about 0.020 mm. by 0.012 mm., light brown in color. Testes slightly oblique or subserial. Gonotyl (Figs. 4 and 56, g) a naked, muscular, stalk-like, cylindrical organ on anterior lip of the ventro-genital sinus, permanently exserted ; its apex bears five root-like processes. The largest of these (Fig. 56) is antero-niedian in position, while a ])air of smaller processes occurs on either side in a postero-lateral position. The cuticula adjacent to the gonotyl is thicker than over the general body surface. Seminal receptacle present. Seminal vesicle (sz' ) largely posterior to the acetabulum. A. artits dififers from z'ariiis. its only congeneric relative, in many points, of which the following are among the more significant: ( 1) form of body (slender in A. arttis, robust in A. z'arius) ; (2) form of gonotyl (cylindrical with five root-like processes at apex in A. art us. a simple crescentic prominence without lobes in A. varius) ; (3) extent of the uterus (transverse loops filling the posterior third of body in ./. z'arius are lacking in A. artiis); (4) shape of the oral spines (in A. varius. Fig. 3, there is no sharp differentiation of root and tip while in A. artus, Fig. 2, the tij) of each oral spine is sharply set off from the root-like base) ; (5) development of prepharynx and esojjhagus (very short or wantin<^' in A. varius. fairly well developed in A. artus). In general aj^pearance, A. artus bears a close resemblance to Crypto(ioni]nus chyli (See Plate 25). The presence of oral spines on A. artus. the form of the gonotyl and its relation to the genital sinus are the only significant points of mor- phological distinction. Types. — Cotypes of AUacaiitliochasmus artus are deposited in the United States National INIuseum, and in the ccjllections of the Roosevelt Wild Life Station, Syracuse, New York. Trematoda: Family Allocreadiidae The genus Crepidostomum is the most abundantly represented luember of this family in the Oneida Lake fauna. The species of Crepidostomum and Megalogonia will be treated in full in our final report. Of the remaining genera in this family, we are here offering descriptions of three new species, one representing the genus Allocreadium (Fig. 5) and two, the genus Triganodistomum (Figs. 6 and 7). Throughout the course of our field collecting we have thought, on numerous occasions, that the living trematodes before us were members of the genus Allo- creadium, l)ut in all of the earlier part of our field study specimens tentatively 86 R()0S('7'rll Wild Life Annals Plate 16. New AUocreadiidae. Fig. 5 : AUocreadimn lialli new species. Ventral view. Fig. 6: Trigaiwdisfoiiiiiiii atfciiiiafitiii new species. Ventral view. F"ig. 7 : Trigauodistoimim sliiicri new species. Dorsal view. Abbreviations ac — acetabulum t — testes cs — cirrus sac ut — uterus gp — ^genital pore vd — vitelline duct ov — ovary vt — vitellaria sr — seminal receptacle 88 Roosevelt Wild I.ifc .huials iclentiticd as Allocreadium proved on closer study of stained specimens to helonj^ to other genera. Finally, in the collections of the summer of 1931, two huUheads were found to carry undouhted specimens of Allocreadiuni. which u])on detailed study ])roved to he a previously undescrihed species. Allocreadium halli new species (Figure 5) Host. — .1 iiu'iiirits iirbiilosits. in alimentarv canal. Two hullheads from the harhor of Cleveland, New York, carried very light infestations with this species. This gives indication that the species is very rare and either has a restricted seasonal distrihution or possesses centers of infestation outside the lake with only an occasional host migrant hringing the worms into the lake fauna. Description. — The sexually mature worms vary in length from 2.5 mm. to 3.5 mm. The body (Fig. 5) is narrow, elongate, with both ends rounded and sides nearly parallel. The oral sucker (0.3 mm. ) is nearly spherical and some- W'hat smaller than the acetabulum (0.4 mm.). The pharynx is about one-half the diameter of the acetabulum, with its length (0.15 mm. ) slightly less than its diame- ter (0.2 mm.). The esophagus is short and quickly branches to form the crura. The crura, which are large and inflated, ajipear as deeply staining, thick-walled, longitudinal sacs. shar]:)ly differentiated in appearance from the esophagus. They reach to the posterior extremity. The genital pore lies on the median line a short distance before the acetabulum. A cirrus sac is present, lapping back over the dorsal surface of the acetabulum. Ovary and testes are rounded, without lobes, the former on the left side at the posterior border of the acetabulum, and the testes contiguous, in tandem fashion, about midw^ay between the ovary and the caudal tip. A receptaculum seminis (Fig. 5, sr) is present behind the ovary. The vitellaria extend from the fork of the intestine to the caudal tip. chiefly lateral. Anterior to the acetabulum they arch over the dorsal surface, meeting in the mid- line, and similarly posterior to the testes they arch over the ventral surface from the two sides, forming a continuous held. The vitellaria are comi)osed of numer- ous small follicles. The uterus is confined to the s])ace between the anterior testis and the ovary, passing once backward and once forward, and loojiing several times transversely. The metraterm crosses the dorsal surface of the acetabulum to reach the genital pore. Pratt (1923:64), in the first survev of the fish ])arasites of C)neida Lake, reports taking some small trematodes from the bullhead, which should be consid- ered in this connection. He states. "In the intestine of one fish also were obtained many slender Trematodes about one millimeter in length, compressed and mounted, belonging to an undescrihed genus allied to Allocreadium." These worms are much smaller than ours. and. if the same form, must have been very young speci- mens. Unfortunately, this material has been lost and is not available for reexamination. Allocreadiuni halli, which is named after Dr. Maurice C. Hall, more closely resembles A. ictaluri Pearse than any other described member of the genus. It PardsilfS of Oneida l.akc l-'islies 89 (lilTcrs from ./. icialiiri in form of the hody, e size of the strobila and of the scolex and the i)rominent terminal disc of the scolex in B. claviceps .serve immediately to diflferentiate it from B. fonuosus. B. Scarpa. B. niaiiuhrifonnis and B. occidciitalis are all large tapeworms found exclusively in marine fishes. In addition to this difiference in habitat, the first two of the foregoing have scoleces much larger than and difi^erent in form from the scolex of B. fonuosus. Though the scolex of B. occidciitalis is not known, the eggs are distinctly larger than those of B. foruiosus. Nematoda: Family Trichinellidae Ward. 1907 In our collections from ( )neida Lake fishes, there are ])resent a considerable number of extremely slender nematodes which, by definition of the Trichinellidae as given by Baylis and Daubney (1926:237), belong within this family and per- tain to the subfamily Trichurinae. From this lot of capillariform worms a new species of Capillaria was described in Part I of this report. Additional specimens of a species inadequately re])resented in our earlier collections were obtained dur- ing the field work of 1931. These worms belong close to the genus Capillaria but have morphological characters which compel us to assign them to the genus Hepaticola in spite of a disharmony in host relationship. Since our specimens are distinctlv different from the described members of the genus, we are recog- nizing them as the basis for the description of a new species. This genus is very imperfectly known, and by Yorke and Maplestone (1926:23) is dififerentiated from the genus Capillaria by a single morphological character. In Cai^illaria there is a spicule in the copulatory apparatus of the male, while in Hepaticola the spicule is lacking. In the last mentioned genus the copulatory a])paratus comprises an eversible membranous sheath, tubular in form but not surrounding a chitinized spicule. In their key to the genera of Capillariinae, Yorke and Maplestone (1926:23) have maintained that occurrence in the liver of rodents (and of man) is a limitation of members of this genus. Inasmuch as the closely related genus Capillaria has a host list embracing the entire vertebrate subphylum, it is not sur- prising to find Hepaticola in hosts other than mammals. The occurrence in the lumen of the digestive tract of a fish instead of in the liver of a mammal is not readily explained, but in light of the wide host tolerance of many nematodes, it does not seem to warrant the erection of another genus, for in morphological details our new species is in clo.se harmon\- with Hepaticola. Consequently we are describing this as a new species under the name Hepaticola baker i. in honor of Dr. Hugh P. Baker, Dean of the New York .State College of Forestry. Panisitcs of Oneida Lake h'islies 103 Hepaticola baked new species (Figures 22 to 30) Hosts. — Lcitcichtliys artedi tullibcc, N otciiiujouus crysolciicas. and Cato- stoiitits coiiiiiicrsoiiii. in the intestine. Description. — I<>niales 7 mm. to 8 mm. long witli a ma.xinium diameter of 0.063 mm. Males 4 mm. to 4.5 mm. in length by 0.045 mm. in greatest width. In females, the esoi)liagus occupies slightly less than half of the body length, the ratio of the esophageal region to the posterior region being about 2 to 3. The para-esophageal cells of the female begin about 0.13 mm. behind tlie tip of the head. The anterior esophagus, lying free in the body cavity, is very wide for one of the Trichinellidae. The para-esophageal series numbers about 38 to 40 cells in the females. These cells are cylindrical, elongate, and have transverse superficial grooves (Fig. 29, div) giving the appearance of more cells than actu- ally occur. There may be four or more of these constrictions to a single cell. The nuclei are large and vesicular, containing a clear sap and a large, liighly refractile nucleolus. The cells are separated by simple transverse partitions. The vulva (Fig. 24, z') lies at the posterior end of the para-esophageal series. The eggs (Fig. 26) are thin-shelled, with polar plugs, and have a length of 0.063 mm. and a diameter of 0.033 mm. A mature female contains 20 to 25 shelled eggs in the uterus. The caudal extremity of the female (Fig. 23) is blunt, with the anus on the ventro-terminal angle. In males, also, the para-esophageal cells begin 0.13 mm. behind the tip of the head. In dififerent worms, we have counted as low as 34 and as high as 38 para- esophageal cells, but the count was m^de from whole mounts. Since the nuclei can not be seen clearly in all cases we can not l)e certain of the exact number or if the number is constant. In the largest males, the esophagus equals one-half the body length. The tail (Fig. 30) is blunt, bent slightly ventrad. and the cloacal opening is terminal. Inside the pore, the cloaca has the form of a long chitinous tube or sheath (sli), into the forward end of which open the vas deferens and the rectum. This sheath is eversil)le. and one of our specimens shows the organ in this condition, extending from the caudal extremity as a curving, double-walled, chitinous tube. Evidently as a result of the muscular activity incident to everting the sheath, the tail in this specimen has a reduced diameter for a short distance before its extremity. The extremity itself is clubbed or knob-like (Fig. 25). The reproductive system of the male is a simple tube extending forward from the vas deferens and looping at the posterior end of the esophagus. The testis extends back toward the tail. This is the first representative of the genus Hepaticola to be reported from the intestine of a fresh-water fish. Types. — Cotypes of Hepaticola bakcri are deposited in the United States National Museum, anfl in the collections of the Roosevelt Wild Life Station, Syracuse, New York. 104 Rooscz'clt Wild Life Annals Plate 20. Hcpaticola bakcri new species. Fig. 22 : Anterior extremity of H . bakcri, showing length of esophagus lying free in b(jdy cavity. The first para-esophageal cell is shown at the bottom of the drawing. Fig. 23: Tail of female H. bakcri, in lateral view. Fig. 24: Mid-region of female showing vulva and transition from esophagus to intestine. Lateral view. Fig. 25 : Tail of male H . bakcri, in lateral view. Sheath everted. Fig. 26 : One egg of H. bakcri. Figs. 27, 28 and 29: Varying appearance of esophageal region of H. bakeri, showing para-esophageal cells without annulations, with narrow separate annulations, and with liroad contiguous annulations. Fig. 30: Tail of male of H. bakcri with copulatory sheath with- drawn, showing length of sheath, relationships, etc. Note anterior limit of chitinous lining of sheath. abbreviations a — anus an — annulation clo — cloaca div — cell boundary e— egg eso — esophagus i — intestine nr — nerve ring nuc — nucleus oj — ovejector ov — ovary pec — para-esophageal cell sd — sperm duct sh — copulatory sheath V — vulva 105 Plate 20 100 Roosevelt Wild Life Annals SECTION 2. REDESCRIPTIONS OF TWO SPECIES OF THE NEMATODE GENUS SPINITECTUS Specimens belonging to the genus Spinitectus have been the most abundantly represented of any of the nematodes encountered in our collections from Oneida Lake fishes. Recent authorities have differed in the location of this genus. Yorke and Maplestone (1926) have definitely assigned it to the family Rictulariidae while Baylis and Daubney (1926) append Spinitectus to the subfamily Thelazi- inae under the Spiruridae. Skinker (1931:374) has referred to the dif^culty involved in separating these two families. Though the specimens of Spinitectus which we have encountered in Oneida Lake fishes during the progress of our field collecting gave evidence of constitut- ing two distinct groups, the tangible basis for separating these became apparent only after the collections had been cleared and subjected to comparative study. There have been but two species of Spinitectus reported from fresh-water fishes of North America. 6". gracilis was described by Ward and Magath (1917) and S. carolini was described by Holl (1928). The latter is supposedly dififeren- tiated from S. gracilis on the ground that papillae are present on the tail of 6". carolini. while Ward and Magath stated that they are lacking on S. gracilis. On the basis of distinctions drawn in the original descriptions of these two species, the present writers were at first convinced that both of the species repre- sented in the Oneida Lake fauna were new. and for a time proceeded on that assumption. One form resembled S. gracilis but possessed papillae in the caudal alae while the other resembled 5". carolini except for the possession of preanal cuticular cleats. After detailed characterizations had been prepared for publica- tion, the essential characters of the two forms checked so closely with those of .S". gracilis and i". carolini that efforts were directed toward a proper evaluation of the points of difference between our specimens and the original descriptions of the two prior species. Since S. gracilis was described from fishes of the Mississippi River at Fair- port, Iowa, specimens from that locality in the collections of one of the present writers (Van Cleave) were examined. In unstained mounts, papillae were read- ily recognizable in the caudal alae of the males but were very much obscured in stained specimens. Professor Ward very kindly placed specimens from the type material of 5". gracilis at our disposal for reexamination. Among the stained whole mounts there was a single specimen of a mature male, but the posterior end of this individual was so oriented that observations were made with greatest dififi- culty. Faint indications of a few papillae could be made out on this specimen but pattern and arrangement of the papillae were wholly unavailable. The simple demonstration of presence of papillae on the type material substantiated by fur- ther evidence of papillae on other specimens from the type locality, lead us to conclude that lack of papillae mentioned in the original characterization of S. gracilis is not a specific characteristic. Since our specimens from Oneida Lake are especially favorable material for demonstration of the caudal alae and papillae and agree in all other respects with the original description of S. gracilis, a rede- Parasites of Oneida Lake I'islies 107 scription of 5". gracilis is presented in this ])a])er, and the tail of the male (l"'ig. 36) is illustrated in detail. The second species which we find in ( )neida Lake has many i)()ints in com- mon with the distinctive characters of .S\ carolini Holl. After makin<^ a careful study of our material, we feel certain that Holl had material of S. gracilis as well as of his new species hefore him when making his description of 5". carolini. The drawing of the anterior end of a Spinitectus given as figure 1 by Holl is undoubt- edly of S. gracilis, while Holl's figures 2 and 3 clearly pertain to S. carolini. The distinctive short right spicule of the male figured l)y Holl is in complete agree- ment with the form of spicule found in our specimens of 5". carolini. We have never found the muscular esopliagus in i'. carolini extending far anterior to the first body spines thougli sucli a condition is regularly present in 6". gracilis. Fur- thermore, the pre-anal plates designated as wanting in the description of 6^. carolini are present in our specimens. In the interest of more complete diagnosis, detailed descriptions of 6^. gracilis and 6". carolini, based upon our extensive collections, are given below. Spinitectus gracilis Ward and Magath (Figures 32, 34 to 36) Hosts. — Esox niger^ Lota maculosa, Ainciurus nebulosus, Pomoxis spa- roides, Esox Indus, Leucichthys artedi tullibee, and less commonly in Aniblo- plites rupestris, Eupomotis gibbosus and Salmo fario, in intestine. Description. — The mature females from Oneida Lake are 10 mm. to 15 mm. long; males shorter, from 8 mm. to 10 mm. Absolute measurements of size are of little value in describing these forms because of their wide range of variation. The constant features are proportions and anatomical characters, as follows : The tip of the head (Fig. 32) is conical, without lips. The head cone passes abruptly into the slender, cylindrical neck region. The first row of spines appears just behind the transition from the cone to the cylindrical portion. The body spines are small and numerous. From 17 to 24 spines are usually visible on one side of each ring so that there are from 35 to 50 spines in each circle. The spines are borne on small rounded papillae which emerge from the edge of collar-like cuticular rings. The first few rings (6 to 8) are farther apart (Fig. 32) than the posterior ones. After about the eighth band, the rings are set almost exactly one-half the interval of those anterior. This abrupt change in spacing is not accompanied by any diminution in size of the spines, and the number in a circle remains the same. The rings or spines are not continuous around the circumfer- ence of the worm but are divided into dorsal and ventral semicircles. These half- rings, at their point of meeting over the lateral lines, are frequently out of line at the junction so that a slight fault is formed. Sometimes, there is a definite dis- continuity marked by an interval without spines. There is a very short oral cap- sule (Fig. 32, oc) and the esophagus in this species begins immediately behind the mouth, far in front of the first ring of spines. The nerve ring lies, usually, between the first and second circles of spines but may be posterior to the third circle. The esophagus is composed of an anterior, slender, muscular region and 108 Roosevelt irild Life Annals Plate 21 S pinitcctus gracilis and S pinitectus carolini. Fig. 31 : Head end of Spinitectus carolini Holl. Fig. 32: Head end of Spinitectus gracilis Ward and Magath. Fig. 33 : Vulvar region of 5". carolini in lateral view, shov^fing short vagina approaching pore from the rear. Fig. 34 : Vulvar region of ^. gracilis, showing long vagina approach- ing pore from the front. Fig. 35 : Tail of female of S. gracilis. Bluntly tapering. Fig. 36: Tail of male of S. gracilis. Short spicule crooked. Fig. 37: Tail of male of .S". carolini. Short spicule arcuate. Fig. 38: Tail of female of 5. carolini. Acutely tapering. abbreviations a — anus cle — cleats on cuticula ge — glandular esophagus i — intestine Isp — left spicule me — muscular esophagus DC — oral capsule oj — ovejector ov — ovarv pap — papillae rsp — right spicule ut — uterus V — vulva vag — vagina 109 110 Roosc-c'clt Wild Life Annals a posterior, thicker, glandular })ortion. The junction between the two regions occurs at or near the level of the change in interval of the spiny rings. The mus- cular region of the esophagus equals al)()ut one-fourth of the organ. The entire esophagus is, in large specimens, equal to only one-ninth or one-tenth of the body length. In large specimens, there is a tendency for the neck to be drawn out into a long, thread-like portion, followed by the thicker region of the body proper. This differentiation of body regions is not always ])resent, hence cannot be depended upon for specific diagnosis. Likewise, the spines, especially in young individuals, show some divergence from the typical arrangement, and therefore cannot be relied upon as infallibly diagnostic. The vulva (Fig. 34, v) lies about one-fourth of the body length from the tail, and the vagina approaches it from the front. A well developed muscular bulb or ovejector is present in this as in other species of Spinitectus. The uterus is bicornuate and branches off from the vagina about 0.8 mm. anteriorly from the vulva, one branch continuing anter- iorly, the other turning and passing posteriorly. The tail of the female is abruptly and obtusely pointed and bears the anus very close to its extremity. The male is similar to the female in the anatomy of the anterior region. The tail is coiled with but a single complete turn in many of the individuals, and has fairly wide alae. ^Stalked papillae (Fig. 36, pap) occur, two pairs pre-anal and three pairs post-anal on either side. Frequently the second papilla of the final pair is lacking or difficult to see. These papillae are borne on slender stalks which are longer than those of the species S. carolini. The left spicule of the male copulatory apparatus is long and gutter-shaped, without any sudden change of form along its length. The right spicule (Fig. 36, rsp) is short, thick, and heavily built. It appears to be bent twice, as seen in side view, each time at aj^proximately a right angle. Actually, the s])icule is twisted much like a ram's horn. The proximal portion would, by this figure, correspond to the base or mouth of the liorn. The ti]) of the spicule is provided with a large lateral barb. It would seem that this spicule serves chiefly as a gubernaculum for the left, longer spicule. A short distance anterior to the cloacal aperture is a series of cuticular ridges or cleats aligned in longitudinal rows. The eggs have a diameter of 0.04O mm. by 0.024 mm. They are provided with heavy shells and each bears a coiled embryo at the time of oviposition. The constant features by which S. gracilis may be safely distinguished are : the male spicules ; pattern of the male papillae ; the position of the anterior tip of the esojihagus ; ratio of esophagus into the entire worm ; size of the eggs and length of the vagina. Other features, not so reliable, are the character of the spina- tion, direction from which the vagina approaches the vulva, and character of the female tail. Spinitectus carolini Holl (Figures 31, 33. .S7, 38) Hosts. — Amhloplitcs nipcstris, Eupomotis gihbosus, Microptcnis do'omicu, in intestine. Description. — Head cone, as in foregoing species, about 0.08 mm. in length, devoid of spines. The mouth has a smooth edge, without definite lips. The Fanisili's of Oneida Lake lushes 111 first circle of body sjjines occurs alxnit 0.08 mm. from the tip. The spines are very long and sharp, usually fewer in the individual circle than in the preceding species — about twenty-five to thirty-five per ring. Each spine is borne on the edge of a collar-like projection of the cuticula. The edges of these collars are stiffened by a heavy bar of cuticula and bear tiie papillar elevations on which the spines occur. As in the preceding species, there is usually some discontinuity in the rings over the lateral lines. Successive rings of spines are separated by an interval of about 0.04 mm. and this interval continues posteriorly, increasing somewhat but with a perfectly smooth trend and without any sudden fluctuations in the females, though in the males the internodes l)etween rings become abruptly smaller at about the twentieth ring. The oral vestibule (Fig. 31, oe) is long, and has the structure of a thin- walled, straight-sided cuticular tube. This joins onto the esophagus at the level of the second ring of spines ( not at the tip of the head as in the preceding species). The esophagus is divided into an anterior, slender, muscular region and a posterior, thicker, glandular portion. The junction between these lies somewhere between the tenth and the fourteenth rows of spines, the exact position varying in dififerent worms. The ratio of muscular to glandular esophagus is as 1 to 5 or 1 to 6. The entire esophagus equals from one-fifth to one-third the length of the worm. The nerve ring surrounds the muscular esophagus usually between the fourth and fifth rings of spines. In this species there is never any tendency toward the slender elongation of the neck region frequently observed in S. gracilis. The vulva (Fig. 33, z') lies a short distance posterior to the middle of the body. Post-vulvar region of body is to pre-vulvar region as 5:4. Ovejector well developed, the vagina approaching it from the rear. The bicornuate uterus branches from the vagina about 0.28 mm. posterior to the pore. The eggs are thick-shelled and each bears a coiled embryo upon oviposition. Eggs are 0.036 mm. long by 0.023 mm. in diameter. The tail of the female (Fig. 38) comes to a long, slender point. It has a very gradual, spear-like taper, as opposed to the blunter, more abrupt termination of 5". gracilis, and the anus in S. carolini is removed a greater distance from the tip. The male is similar to the female in the anterior body region. The tail (Fig. 37) is usually thrown into a coil of two or three complete turns. Narrow alae are present. The tail is long and slender and the anus farther removed from its tip than in the preceding species. The papillae are provided with short, thick, stalks and tend to be evenly separated rather than paired. The arrangement is four pre- anal and five post-anal papillae on either side of the tail. The right spicule (Fig. 37, rsp) is short and arcuate. Its distal end is pointed, while proximally it is, expanded. The tip is provided with a large ventral barb. From the large proximal end of the shaft a long curved plate or scute arises and follows along the ventral surface of the spicule, terminating in a point which projects toward the barb. The long left spicule is slender and evenly curved with the general direction of the tail. Its proximal portion is tubular, but about half way along its length it becomes suddenly compressed and rounded into a gutter or trough. The point lies near the barb of the right spicule. Some distance anterior to the anus is a series of par- 112 Roosevelt Wild Life Annals Plate 22. The anatomy of Microphallus ovatus. Fig. 39 : Detail of cross section of M. ovatus in region of genital pore. Edge of acetabulum seen at left. Fig. 40: Detail of longitudinal section of .1/. ovatus, in region of genital pore. Position of acetabulum and of metraterm dotted in. Fig. 41 : A surface view and frontal sections at three dil¥erent levels, of the genital complex in M. ovatus. A depression of the surface encloses the acetabulum and the genital orifices but is not the equivalent of the ventro-genital complex of the Heterophyidae. Fig. 42 : Diagram of genital complex in Microphallus. Fig. 43 : Ventral view of a toto mount of M. ovatus. abbreviations ac — acetabulum ex — e.\cretory bladder Is — lip of ventro-genital sinus rn — metraterm p — penis pr — prostate sr — seminal receptacle ut — uterus vd — vitelline duct vs — vesicula seminalis vt — vitellaria 114 Roosevelt Wild Life Annals allel, longitudinal rows of cuticular cleats. These are indistinct in some specimens but are not lacking as stated by HoU. This worm is smaller than the foregoing species. The mature females are usually from 7 mm. to 8 mm. long at most, and the males are slightly smaller. ^. carolini may be definitely recognized by the following constant characters: shape of the spicules ; long oral vestibule with esophagus starting ha.ck of the first circle of spines ; ratio of esophagus to body length ; size of eggs. The following characters are typical but less constant : position of vulva and direction from which the vagina approaches it ; the character of the spination ; shape of the caudal tip of the female. SECTION 3. SYNOPSIS OF THE FAMILY HETEROPHYIDAE (TREMATODA) FROM FRESH-WATER FISHES OF NORTH AMERICA Many of the trematodes reported from fresh-water fishes of North America have been the objects of speculation by various authors who have failed to agree upon their relationships. One of the sources of this confusion has resulted from attempts on the part of .some investigators to complete a taxonomic system when available evidences are too meagre to warrant more than a guess at the proper allocation of some of the genera. Many attempts at fitting trematodes from fishes into the general scheme of classification have been made by students interested in details of a portion of a single system, such as the form of the excretory bladder or the topography of the protonephridial system. Important as these individual sys- tems are in reflecting degree of phylogenetic relationship, they give but one line of evidence wliich must be confirmed by facts from the morphology of other organ systems and from the life cycle. Preconceived notions as to restrictions of certain groups of trematodes to the limits of certain classes of vertebrate hosts have like- wise contributed to the failure of some workers to sense relationships of some of the fish distomes. The writers have studied large numbers of living and preserved collections of trematodes in the course of the survey of fish parasites of Oneida Lake. These investigations have extended over a period of years during which many shifts in tentative conclusions have been necessitated by new lines of evidence. In these studies, an examination of the living worms has frequently offered suggestions as to possible relationship between forms which were originally thought to be entirely distinct. These leads have been followed by the study of whole mounts and serial sections. The fragments of evidence from all available sources, when pieced together, have pointed definitely to a possible solution of many of the dis- puted questions of supra-generic relationships of the fish trematodes. One of the outstanding results of this study has been the determination of the fact that several genera from fresh-water fishes belong to the family Heterophyidae. Another conclusion is that the genus Microphallus, though very commonly assigned to the Heterophyidae has no direct relation to that family. Because of their occurrence in mammals and in birds, and their normal or potential infestation of man, the j^reviously known heterophyids have been given considerable attentif)n. In si)ite of numerous studies on members of this family, Parasites of Oneida Lake I'islies il5 there has been, until recently, a pronounced lack of agreement as to details of morphology in its ineml)ers and even the confines of the family have been under bitter dispute. Witenberg (1929) has made an especially noteworthy contribution to an understanding of the reproductive organs and the copulatory apparatus in members of this family. His is the most coni])rehensive systematic treatment of the Heterophyidae that has appeared in the literature. Five subfamilies are recog- nized in his system, two of which were new in his 1929 monograph. In the same monograph he excluded from the family a number of subfamilies and genera which Poche (1926) and Nicoll ( 1909) and others had previously ascribed to it. Among these excluded groups are the Microphallinae and the Gymnophallinae, omitted because both lack a seminal receptacle, and in addition, because the former con- tains reputed members which are provided with a cirrus pouch. The Heterophyidae have been very generally considered as characteristically reaching the adult state in mammals and birds. In referring to the genus Haplor- chis of Looss, Witenberg (1929:200) states: "Two species of the genus Haplor- chis are known: H. caharinus (Looss, 1896) and H. pHuiilio (Looss, 1896). It is noteworthy that the first is the only species of Heterophyidae found in the adult state as a parasite of fish. This circumstance leads to the supposition that H. caharinus may belong to quite another family". The present writers have not studied specimens of Haplorchis and find that the descriptions and drawings in the literature are inadequate to serve as a basis for reaching any final conclusions in this matter. However, as shown in the present paper, seven genera of trematodes in the North American fauna regularly occur in fish, yet show characteristics which indubitably unite them with the Heterophyidae (see Van Cleave and Mueller, 1931). Vietosoma, Acetodextra, Allacanthochasmus, Neochasmus, Cryptogoni- mus, Caecincola and Centrovarium are all normal parasites of fish. In fact, exten- sive faunal surveys have failed to yield any evidence that members of these genera ever occur normally in either birds or mammals. Consequently there is no possi- bility that these heterophyid genera are avian or mammalian parasites accidentally misplaced in fishes. The complete agreement of these seven genera with the mor- phological concept of the Heterophyidae, necessitates the revision of the concept of that family to include the fishes as normal hosts to the heterophyids. In a footnote, Witenberg (1929:135) calls attention to the fact that the "Heterophyidae are not the only Trematodes with such a complicated genital sinus. Similar structures are also present in other groups of Trematodes, for instance Microplialhis, Heiiiiuridae, Asygiidae, etc." After a most thorough investi- gation of the genital apparatus of Microphallus and of several species of Azygia, the present writers find no difficulty in sharply differentiating between the copulatory modifications and genital sinus of these forms and the ventro-genital complex of the heterophyids. Witenberg's statement regarding the presence of structures similar to those found in the Heterophyidae must be interpreted in the broadest manner, for in the forms which we have investigated there is only the vaguest functional similarity in parts. On the contrary, the genitalia of Vietosoma, Acetodextra, Allacanthochasmus, Neochasmus, Cryptogonimus, Caecincola and Cen- trovarium are in intimate agreement with the plan of organization generally recog- nized as distinctive for representatives of the Heterophyidae. In five of these seven enumerated genera, the morphological plan is so similar that a chart has been pre- 116 Rooscz'cll Wild Life .liuials Plate 23. Fish trematodes of tlie family Heterophyidae. Fig. 44: Vietosoina parvum. a heterophyid lacking a gonotyl. Fig. 45: CryptogoniiiiKs chyli in ventral view. A heterophyid with a typical gonotyl. Fig. 46: Ac etod extra amiuri in ventral view. A heterophyid with a large gonotyl. Fig. 47: Detail of ventro-genital sinus of Cryptogoninius, in ventral Fig. 48 : Side view of ventro-genital sinus of Cryptogoninius. Fig. 49: Detail of ventro-genital sinus of Acetode.xtra. in sagittal Fig. 50: Detail of ventro-genital sinus of Acetodextra, surface view of a toto mount. view. section. abbreviations ac — acetabulum cr — crura es — eye spots ex — excretorj' bladder g — gonotyl gp — genital pore Is — lip of ventro-genital sinus m — metraterm ov — ovary sr — seminal receptacle t — testis ut — uterus vd — vitelline duct vs — vesicula seminalis vt — vitellaria 117 Plate 23 118 Rooscc'clt Wild Life .-linials pared (Plate 25) showing the gradual transition of conditions from two stem forms through varying modifications especially of the ovary and of the gonotyl. On the strength of the foregoing evidences, details of which will be set forth in tlie follow- ing section, it seems necessary to modify the definition of the Heterophyidae to include fishes as possible normal hosts of members of this family. Accepting W'itcnberg's formulation of characters, the definition of the family sliould be as follows : Family Diagnosis. — Small to very small treniatodes with the body covered with scale-like spines and frequently with a crown of circuni-oral spines. Pharynx always present. Body usually divided into a motile anterior, flattened region devoid of genitalia, and a posterior part containing the genital organs. Ventral sucker usually reduced and intimately associated with the genital pore. Genital ducts usu- ally opening into a common genital sinus which frequently contains a copulatory organ known as a gonotyl. Genital pore either median or lateral in position. Ovary and testes highly variable in shape, the ovary almost always anterior to the testes. Cirrus pouch lacking. Seminal receptacle voluminous. Uterus usually not extend- ing anterior to the genital pore. Parasitic in mammals, birds and fishes. As thus conceived, the family is such a heterogeneous assemblage that limitation by definition of positive characters becomes extremely difficult. Yet, among them- selves, the forms here brought together possess a unity of organization that may be sensed by the experienced worker before the detailed i)oints of morphological agreement have been studied out. Thus, the diversity of form and organization here manifested seems to issue as an expression of evolutionary progression (see Plate 25) rather than give evidence of accidental convergence or parallelism. The extent to which evolution has led to diversification is clearly demonstrated by citing a few specific instances of variable conditions in this family. Circum-oral spines may be either present (Fig. 63) or lacking (Fig. 62) ; either one or two testes may be present ; the ovary may be either pre- or post-testicular and in form ranges from spheroidal to follicular ; uterine loops may be either wholly pre-testicular or extend to the extremity of the body ; and even the ventro-genital sac varies widely in posi- tion as well as in the extent of development or of suppression of its component parts. For instance, the gonotyl, one of the most distinctive organs representing a peculiar morphological substitution for the cirrus within many members of this family, may be entirely lacking in some genera (Figs. 65 and 66). While the gonotyl very commonly occupies a position in the ventro-genital com- plex anterior to the acetabulum, as in Hctcropliycs Jictcropliycs. its position is highly variable in some other genera. Thus, in Rossicotrema, according to Witen- berg (1929:183), there are two small gonotyls at the sides of the genital aperture, while for Dexiogonimus the same authority regards two papillae guarding the ante- rior and posterior margins of the ventro-genital sac as a peculiarly modified gonotyl. Detailed attention is given to this matter of instal)ility in location of the gonotyl because confusing irregularity has been encountered in the genera considered in this paper. That degrees of relationship within the family Heterophyidae are not clearly shown by conditions of the gonotyl, is shown by the fact that in a single genus ( Parascocotyle) two fundamentally dififerent conditions occur. In P. italica, according to Witenberg, there is a single, small, oval gonotyl anterior to the ventral Parasites of Oneida Lake I'isltes 119 sucker, while in P. loiuja there are two widely separated gonotyls located anterior and lateral to the ventral sucker. With the understanding that citation of hkenesses does not tacitly imply argu- ment for close relationship, the variable conditions in the genera from North Ameri- can fishes parallel those described for earlier genera by Witenberg. These i)arallels are as follows: the gonotyl in Neochasmus (Figs. 53 and 69) is posterior to the ventral sucker as in Heterophyes ; the gonotyl in Allacanthochasmus, Crypto- gonimus, and Acetodextra is anterior to the ventral sucker and the genital pore as in Parascocotyle italica; the gonotyl is either completely lacking or has not been recognized in Vietosoma, Caecincola, and Centrovarium, therein paralleling Diorchitrema (Witenberg, 1929:174). Subfamilies of the Heterophyidae The family as recognized by Witenberg (1929) includes five subfamilies, but as emended and extended by the present writers (Van Cleave and Mueller, 1932), a sixth subfamily is added to the list, as follows : 1. Heterophyinae Ciurea, 1924 2. Centrocestinae Looss, 1899 3. Haplorchinae Pratt, 1902 4. Cercarioidinae Witenberg, 1929 5. Adleriellinae Witenberg, 1930 6. Neochasminae Van Cleave and Mueller, 1932 Adhering to the view that the Heterophyidae, as an entire family, are restricted to avian and mammalian hosts, Witenberg (1929) has made no direct reference to host limitations in diagnosis of the subfamilies. The fact that five of the genera from North American fishes fit readily and naturally into the Hetero- phyinae by the simple extension of the host list to include fishes as possible adult hosts, leads us to propose an emendation of the subfamily Heterophyinae. By extending the bounds of this sulifamily, we avoid the necessity of creating a new subfamily for Acetodextra and another for Vietosoma. Likewise the Cryptogoni- minae of Osborn (1903), though never previously assigned as a subfamily under the Heterophyidae, is based upon a concept which falls wholly within the Hetero- phyinae except for the fact that its members are from fishes. If thus emended, the subfamily Heterophyinae would include the following genera characteristically found in fresh-water fishes of North America: Vietosoma, Acetodextra, Cryptogo- nimus, Caecincola, and Centrovarium. The genera Neochasmus and Allacantho- chasmus cannot be accommodated in this or any other generally recognized sub- family. It was for this reason that the present writers (Van Cleave and Mueller. 1932) established the subfamily Neochasminae for the former of these genera. Recent studies presented in this paper for the first time have yielded results which permit the inclusion of Allacanthochasmus in the subfamily Neochasminae. It has seemed to the writers that the diagnosis of the subfamily Heterophyinae is lacking in enumeration of positive characteristics. However, for the purposes of the present synopsis, the delineation of Witenberg is accepted with the simple 120 Roosc7'clt Wild Life .hi mils extension to include fishes as normal hosts of this subfamily. With this shght emendation. W'itenberg's characterization is as follows: Srni AMii.Y Heterophyinae Ciurea. 1924 Diagnosis. — Body more or less flattened, more so anteriorly than posteriorly ; no dilation of the anterior extremity; no circum-oral spines; two testes situated behind the other reproductive organs. Reaching the adult stage in mammals, birds and fishes. In the following paragraphs the genera newly ascribed to the Heterophyinae will be discussed and the morphological evidences supporting the assignment to this subfamily will be set forth individually for each genus. Heterophyinae: Genus Vietosoma Van Cleave and Mueller, 1932 (Figure 44) The genus Vietosoma, described in Part I of this report, shows such marked resemblance to the genus Euryhelmis (= Distorna squaimila) that parallelism does not seem as readily available for explaining the likenesses of the two forms as does an assumption of phylogenetic relationship. The striking similarity between Eury- helmis and Vietosoma was set forth in the original description of the latter (Van Cleave and Mueller, 1932:16). At that time structures which were interpreted as a cirrus and cirrus sac were described for Vietosoma, but in rechecking our material we have discovered that these structures were misinterpreted and that in plan of organization the ventro-genital sac of Vietosoma is distinctly heterophyid. The inti- mate agreement of Vietosoma and Euryhelmis can find expression only by assign- ing the two genera to the same subfamily. At the time when he prepared his monograph on the Heterophyidae, Witenberg (1929) declared that the morphology of Euryhelmis was too little known to permit of its admission to the Heterophyidae. This exclusion was contrary to the expressed opinion of Poche (1926:150), who, in replacing the preoccupied name Eurysoma with the valid designation Euryhelmis, assigned the genus to the hetero- phyid family. It remained for Baer (1931) to make a detailed morphological study of Euryhelmis. thereby providing the conclusive evidence of its family relation- ship. The demonstration of a clearly defined ventro-genital sinus, bearing a per- fectly characteristic gonotyl, removed the last vestige of doubt concerning the assignment of Euryhelmis to the Heterophyidae. Since Euryhelmis is accorded an unimpeachable status within the subfamily Heterophyinae on the basis of Baer's morphological study, and was assigned to that subfamily by that author as well as by previous workers, we have no hesitation in proposing to place Vietosoma in the Heterophyinae. In details of organization of the ventro-genital apparatus, the genus Vietosoma offers some ])eri)lexing problems. A study of whole mounts gives evidence of a dififerentiated ovoidal mass lying anterior to the ventral sucker. In surface view this mass is strikingly similar to a gonotyl. In fact, the surface view of the ventro- genital complex is almost identical with that figured by Baer ( 1931, Fig. 17b) for Euryhelmis. However, in serial sections of Vietosoma we have been unable to Parasites of Oneida Lake Irishes 121 demonstrate the presence of any structnre that might he called a gonotyl. The minute size of the worm makes interpretation of details of morphology extremely ditficult. In serial sections, the genital ducts of both sexes are clearly demon- strable, for both open in truly hetero])hyid manner by a common a])erture at the anterior border of the ventral sucker. This condition does not form a basis for excluding Vietosoma from the Heterophyinae, for, as shown in an earlier para- graph, the gonotyl may be either present or wanting in the heterophyids. Heterophyinae : Genus Acetodextra Pearse, 1924 (Figures 46, 49, 50) In 1900, J. Stafford described a trematode from the liver and the air bladder of a catfish, under the name of Monostommn amiuri. He expressed the belief that the name by which he had "chosen to designate it, can not, as far as I at pres- ent see, prove either vague or conflicting." In 1924, A. S. Pearse erected the genus Acetodextra to contain as type Stafford's reputed monostome. The original defini- tion of Acetodextra definitely calls attention to the presence of a dextral acetabulum, and while the genus was removed from the monostomes to the distomes, Pearse made no further attempt to allocate it with reference to family or subfamily groups. No subsequent author has offered evidence of the systematic position of Aceto- dextra, until the present writers (Van Cleave and Mueller, 1931), in a preliminary abstract, proposed placing this genus in the family Heterophyidae. By emending the diagnosis of the Heterophyinae to include fishes as natural hosts of this sub- family, the genus Acetodextra may be accommodated in this subfamily. A preliminary study of stained whcple mounts (Fig. 46) of Acetodextra amiuri (Stafford), from the swim bladder of Auieiurus nebulosus and Anieiurus nataJis from Oneida Lake, gave evidence of intimate association (Figs. 49 and 50) of the acetabulum and another sucker-like organ originally interpreted as the genital pore. In Stafford's drawing accompanying the original definition of Acetodextra amiuri (1900, Fig. 2) the acetabulum is plainly figured, as Pearse (1924:147) has previ- ously stated, and in addition, a second sucker-like organ is represented adjacent to the anterio-mesial margin of the acetabulum. This last mentioned structure is evi- dently what the present writers were at first inclined to consider as a highly modi- fied genital pore, and Pearse (1924:147 and Fig. 6) seems to have made the same interpretation. Later, a study of whole mounts under high magnification and with more favor- able illumination, revealed the fact that a groove-like depression (Fig. 50) connects the acetabulum and the second sucker-like organ and that the genital pore lies within this groove at the margin of the acetabulum The details of the relationship between genital pore, acetabulum and the sucker-like body were studied out in serial sections (Fig. 49). In all essential details, these parts are in complete agreement with the ventro-genital complex which Witenberg (1929) has described for members of the family Heterophyidae. The acetabulum is not located on the surface of the body but is so deeply submerged that in cross sections of the worm, in some instances, it is about equidistant from dorsal and ventral surfaces. In frontal sections, a lenti- cular body, similar in shape to that described by early workers on the Hetero- 122 Roosevelt Wild Life Annals Plate 24. Fish trematodes of the family Heterophyidae. Fig. 51 : Neochasinns uinbellus in ventral view. Fig. 52 : Detail of genital complex of A'', umbellus, in surface view. Fig. 53 : Detail of genital complex of A^. mnbellns, in side view. Fig. 54: Detail of poral region of A'^. umbellus. Fig. 55: AUacantlwchasmus artus, for comparison with Fig. 57. Fig. 56: Detail of genital pore complex in A. artus. At the left, are shown the tip of the gonotyl (above) and a cross section through the base of its stalk (below). Fig. 57: Ventral view of toto mount of AUacantlwchasmus varius for comparison with A. artus shown in Fig. 55. Fig. 58: Cross section through A. z'arius in region of gonotyl (g), showing also cross section of the common genital duct (d). Fig. 59: Cross section through acetabular region of A. varius. Fig. 60: Sagittal section through genital complex of A. varius, showing gonotyl, genital duct and acetabulum. Fig. 61 : A. varius, surface view of ventro-genital complex, from a toto mount. abbreviations ac — acetabulum d — genital duct g— gonotyl ov — ovary ph — pharynx t — testis ut — uterus vs — vesicula seminalis vt — vitellaria gp — genital pore Is — lip of ventro-genital sinus m — metraterm OS — oral sucker 123 Plate 24 124 Roosc-rclt Wild Life Annals phyidr.e. is readily distinguishable within the second sucker-like body of the ventral surface. This body is clearly the direct equivalent of the modified male copulatory organ or gonotyl as described and named by Witenberg (1929:235). In sagittal sections the gonotyl (Fig. 49, g) is cut in a plane approximately transverse to its long axis, hence in a single section it has the appearance of a small copulatory pai:)illa such as has been described by several authors for Microphallus and other genera. However, the gonotyl of Acetodextra does not surround the terminal por- tion of the ductus ejaculatorius as in Microphallus. Instead, both genital ducts open into a common atrium (Fig. 49) which communicates with the surface by a single genital pore lying between the acetaliulum and the gonotyl. There is no direct continuation of the male duct and the gonotyl. To the present time we have been unable to find specimens of Acetodextra with the gonotyl exserted. In many of our specimens, the gonotyl is so tightly drawn back into the genital sinus that it is distinctly flattened and gives no clue to its form during copulation. The gonotyl is especially difficult to demonstrate in large speci- mens. This fact seems to be correlated with the observation that mature worms of this species store the eggs within the body and that the body finally undergoes senescence and disintegration in the swim bladder of the host. It is entirely possible that the initiation of degenerative changes leads to the absorption and final disap- pearance of some organs, including the gonotyl, before the complete dissolution of the body. General topography of the other organ systems, as well as the details of the ventro-genital complex, gives additional evidence of the heterophyid relationships of Acetodextra and warrants its being ascribed to the subfamily Heterophyinae. Heterophyinae : Genus Cryptogonimus Osborn, 1903 (Figures 45, 47, 48, 62, and 64) The genus Cryptogonimus was originally described as having two ventral suckers. All subsequent authors, except Fuhrmann (1928:118), have quoted Osborn (1903:316) and have idealized one of his original figures but have failed to give consideration to his drawing of a sagittal section. Otherwise, an interpre- tation of this second ventral sucker would have been made earlier. In this figure, as well as in his description, Osborn shows that "These suckers are contained within a sheath formed as a depression of the ventral surface, and having a lip furnished with a circular sphincter muscle capable of closing the lip to a considerable extent and thus enclosing the suckers. The genital opening is located in the middle line between these suckers, it is thus entirely within the sheath, whence the generic name assigned." The acetabulum and its associated organs thus described form a per- fect picture of the ventro-genital complex of the Heterophyidae. Poche (1926:165) placed the genus Cryptogonimus in the family Acanthostom- idae. In this he followed Odhner (1911:522), but at that early date the nature of the ventro-genital apparatus of the Heterophyidae was very imperfectly under- stood, and the significance of the ventro-genital complex in taxonomy of the trema- todes was not at all appreciated. Fuhrmann (1928:118) sensed the fitness of including Cryptogonimus in the Heterophyidae even though details of the genital complex were probably unknown to him. According to his scheme, Cryptogonimus Parasites of Oneida Lake Pishes 125 was ])laced in the subfamily Heterophyinae where we are content to allow it to remain. Old evidence construed in the light of new interpretations renders Poche's assignment to the Acanthostomidae untenable and gives validity to Fuhrmann's decision. In sagittal sections, the "double ventral sucker" of the original description, quoted so generally by subsequent writers, proves to be a portion of the ventro- genital complex within a depressed area (Figs. 47 and 48) consisting of a sub- merged acetabulum and a gonotyl with the genital pore between them. The gonotyl of Cryptogonimus may be cupped, like an acetabulum, but more commonly the end is flattened. The gonotyl (Figs. 47 and 48, g) almost fills the ventro- genital sinus and its large, blunt end either protrudes slightly from the orifice or is almost flush with the body surface. In all essential details, specimens of Cryptoyonimus chyli agree with Witen- berg's diagnosis of the family Heterophyidae and with the typical subfamily as emended in this paper. In the original characterization of the genus, Osborn defin- itely stated that a seminal receptacle is lacking. This in itself would tend to throw doubt upon heterophyid affinities for Cryptogonimus. However, we have been able to demonstrate a seminal receptacle (Fig. 45, sr) in our specimens. This organ lies anterior to the ovary and to the left. In some specimens this is diiTicult to demon- strate because of the readiness with which it may be confused with the seminal vesicle (Fig. 45, vs). The extent of the uterus was at one time deemed a limiting character marking membership in the Heterophyidae. More recent workers have not agreed with Ran- som (1920:528) in specifying that the heterophyid uterus must be pre-testicular. Thus, for example, though the genus Parascocotyle is unquestionably heterophyid, its members show great diversity in uterine extent. In P. longa the uterine loops are wholly pre-testicular, while in P. italica they occupy the entire area behind the genital orifice, extending post-testicularly to the extreme end of the body. Similar contrasts are found in the dififerent species of the genus Ascocotyle of which Tra- vassos (1930) considers Parascocotyle a synonym. No character so inconsistent within a genus can be entrusted with significant value in determining family limits. Hence, the present writers are in accord with Witenberg in his omission of refer- ence to the extent of the uterus in diagnosing the family Heterophyidae. In ascribing the genus Cryptogonimus to the subfamily Heterophyinae, atten- tion should be called to the fact that Osborn (1903) erected a subfamily Crypto- goniminae to accommodate his genus but of¥ered no clue as to the family relation- ships of his newly recognized subfamily. In view of the recharacterization of the Heterophyinae given earlier in this present paper, the genus Cryptogonimus would fall naturally within the subfamily Heterophyinae. Consequently, we propose to reduce the name Cryptogoniminae Osborn to direct synonymy with Heterophyinae. Heterophyinae: Genus Caecincola Marshall and Gilbert, 1905 (Figure 65) The genus Caecincola seems to have a very close relationship to the genus Cryptogonimus (Figs. 64 and 65). Its only species, C. parviila, displays morpho- logical characters which are closely parallel to the organization of Cryptogonimus 126 Roosevelt Wild Life A>uuils ehyli. Tliouj,'h neither cirrus nor cirrus sac is present, we have, so far, been unable to demonstrate the presence of a gonotyl. However, the presence of the gonotyl is not essential for inclusion within the family Heterophyidae. Hence we are includ- ing Caecincola as a heterophyid within the subfamily Heterophyinae. Though disagreeing with Odhner (1911:522) and with Poche (1926:165) on the disposition of Caecincola and Cryptogonimus in the system of the trematodes, the present writers are in full agreement with both of the above mentioned authori- ties in the expression of a belief that Caecincola and Cryptogonimus are closely related. General morphological evidences permit the use of the bond of relation- ship reflected in general topography of the organs to bind these genera to the Heterophyidae rather than to Acanthostomidae as proposed by Poche. The short crura, lateral testes, lobed ovary, strong development of the Y-shaped excretory bladder sending its two arms forward to the esophageal region, the limitation of the lateral vitellarian zone, and the method of coiling of the uterus all give evidence of close agreement in the morphology of Cryptogonimus, Caecincola and Centrovarium. Since, added to these characters, Cryptogonimus possesses a gonotyl. its heterophyid nature is established and similar assignment to Caecincola and Centrovarium must follow. Heterophyinae: Genus Centrovarium Staflford. 1904 (Figure 66) On the basis of general topography of all the important organs and systems, the genus Centrovarium (Fig. 66) shows a close parallel in detail to the plan of organization found in Cryptogonimus (Fig. 64) and Caecincola (Fig. 65). In much the same spirit that former authorities have sensed the relationship between Cryptogfinimus and Caecincola on the basis of general ]^lan of structure (even though the authors have differed radically in the assignment of the paired genera), we feel forced to tie Centrovarium with Cryptogonimus and Caecincola. We assign Centrovarium to the subfamily Heterophyinae. In Centrovarium the common genital duct which opens through the common genital pore is very short, as in other heterophyids described in this paper. The metraterm and uterus comprise the ventral branch of the fork while the ductus ejaculatorius forms the dorsal branch. This arrangement of the genital ducts seems to be highly characteristic of the Heterophyidae of fishes and adds another point to the list of evidence of unity of the group. Subfamily Neochasminae Van Cleave and Mueller, 1932 Diagnosis. — Parasitic in digestive tract of fresh-water fishes. Ventro-genital sac median, associated with a single gonotyl. Mouth surrounded by a single crown of spines. Dorsal lip somewhat thickened. Vitellaria lateral, in mid-zone of body. Ovary a pre-testicular. transverse band of follicles. Testes two, spheroidal, at considerable distance from posterior extremity. Uterus chiefly post-testicular. Type genus. — Neochasmus Van Cleave and Mueller, 1932. Additional genus .•Mlacantliochasmus Van Cleave, 1922. Parasites of Oneida lAike Fishes \27 At the time the genus Neochasmus was described, the authors (Van Cleave and Mueller, 1932) interpreted some of the structures found in that genus to be so distinct from those encountered in the older genus Allacanthochasmus that a sub- family was erected to include Neochasmus alone. Subsequent studies of two species of Allacanthochasmus have confirmed the original belief that Neochasmus and Allacanthochasmus stand as shari)ly differentiated genera, but have failed to substantiate the belief that the two genera represent different subfamilies. Thus, in spite of the fact that Allacanthochasmus is the older and possibly the more typi- cal genus, the name Neochasminae has been definitely proposed in print and must stand as the designation for this subfamily. Neochasminae: Genus Neochasmus Van Cleave and Mueller, 1932 (Figures 51 to 54, and 69) Specimens of the species Neochasmus uiiibellus have been studied in detail to determine the systematic position of the members of this genus. In this study, the validity of the subfamily Neochasminae has been confirmed and the location within the Heterophyidae has been substantiated. The acetabulum in this genus is deeply submerged (Fig. 54, ac) as in Allacan- thochasmus and is intimately associated with the genital sinus. The rudimentary gonotyl (g) is a surficial modification of the posterior lip of the genital sinus. In this point Neochasmus differs markedly from Allacanthochasmus in form and loca- tion as well as in degree of development of the gonotyl. The two species of Alla- canthochasmus and N^cochasiinis uiubellus constitute a progressive series in the degeneration of the gonotyl (Figs. 67 to 69). In both species of Allacantho- chasmus, the gonotyl lies anterior to the genital pore, outside the genital sinus. In this position it is permanently exposed and not susceptible to eversion and retrac- tion as in some other heterophyids. The prominent gonotyl of A. art us is replaced by a diminutive surficial papilla in A. varius and is still further reduced in Neochas- mus. The genital sinus receives the ducts from both ovary and testes and com- municates with the exterior through a clearly defined and highly differentiated genital pore anterior to the submerged acetabulum (Fig. 54). Specimens observed in side view demonstrate clearly the presence of a distinct enlargement of the dorsal lip of the oral sucker, though no cecum or posterior appendage to the sucker is present as in members of the subfamily Centrocestinae. In all points of structure, Neochasmus agrees with the current characteriza- tion of the family Heterophyidae except in the form of the ovary. As mentioned by the present writers (1932:24), the follicular ovarian band of Neochasmus does not constitute a palpable quantitative difference from the variable conditions of "globular or slightly lobed" given in Witenberg's diagnosis of the family, but merely extends the range of recognized variation. The ventro-genital complex, the form of the excretory bladder, and the general topography of the entire worm combine to substantiate the claim of heterophyid relationship for Neochasmus. 128 Roosevelt Wild Life Annals Plate 25. Chart showing evolutionary tendencies in the Heterophyidae inhabiting the alimentary canal of fishes. Cryptogonhnus chyli and AUacanflwchasniiis artus are two forms agreeing in all essential morphological details except in the form and position of the gonotyl and in the fact that the latter species bears a circle of oral spines. About these two stem forms, the hetero- phyids living in the alimentary canal of American fishes may be arranged in two series showing progressive changes. In the series consisting of Cryptogonimus chyli (Fig. 64), Caecincola pannila (Fig. 65), and Centrovariiiui lohotes (Fig. 66), the ovary becomes progressively more lobed and the crura more reduced. The gonotyl characteristic of Cryptogonimus disappears in Caecincola and in Centrovarium but the general resemblance in morphology remains throughout the series. In the series of forms characterized by the possession of oral spines, the ovary undergoes progressive fragmentation into follicles. Start- ing with a lobed ovary in Allacanthochasuius artus (Fig. 67), the lobes are replaced by separate follicles in A. varius (Fig. 68) and in Ncoclwsinus iiinhellus (Fig. 69). In this series also, there is progressive abbreviation of the crura and gradual diminution of the gonotyl until a vestigial structure replaces the functional gonotyl in Neochasmus. 129 130 Roosczrlt Wild Life Annals Neochasminae : Genus Allacanthochasmus \'an Cleave, 1922 (Figures 1 to 4, 55 to 61, 63, 67 and 68) \\'hen one of the authors of this paper defined the genus Allacanthochasmus (\'an Cleave, 1922:3). no definite family relationship was designated, though com- parisons were drawn with certain other genera. Poche (1926:165) in his mono- graphic treatise on the taxonomy of the Trematoda, ascribed Allacanthochasmus to the family Acanthostomidae, evidently founding his action upon statements and comparisons occurring in the original description and upon the opinion of Odhner who believed that neither presence nor absence of oral spines is as safe a criterion of relationship as is general topography of the organ systems. A reinvestigation of the morphology of Allacanthochasmus I'arius, together with studies on a new species, A. arfus. has revealed several new facts which for the first time provide the grounds for a valid determination of the family relationships of this genus. Following the preliminary study of the genus Neochasmus, the authors of the present paper were of the opinion that details of the organization of the ventro- genital complex in that genus j^recluded the inclusion of Neochasmus and Allacan- thochasmus in the same subfamily. Consequently a new subfamily, the Neochas- minae, was defined in F^art I of this report. Subsequent study of the literature has revealed the fact that the difi^erences between Neochasmus and Allacanthochasmus are no greater than similar differences between related genera which Witenberg and other authorities include within the same subfamily concept. In consequence, the genus Allacanthochasmus is assigned to the subfamily Neochasminae. In the original description of A. varius, mention was made of a "crescentic ele- vation which l)ears the genital orifice". Recent studies by the present authors, upon living worms and upon serial sections have made clear the true nature of the crescentic elevation mentioned above. Instead of its representing a simple genital pore, it proves (Figs. 60 and 61, <;) to be the gonotyl of a clearly defined ventro- genital complex. The form of the gonotyl with its crescentic concavity directed anteriorly is clearly figured in the original drawing of the "genital pore" in the original description of the species (Van Qeave, 1922, Fig. 2). The true genital pore (Fig. 6\, d) is a minute opening between the gonotyl and the ventral sucker, not shown in the original drawing. In field studies of living specimens of Allacaiithochasinus aitiis. the ventro- genital complex has been studied in, its varying conditions, and on a number of occasions the gonotyl has been observed in side view. Even in preserved specimens the gonotyl may be seen projecting beyond the body when entire worms are mounted in side view. It protrudes prominently anterior to the ventro-genital sinus near the anterior margin of the acetabulum as a distinct papilla (Fig. 56)' bearing a series of five enlargements on its free extremity. The gonotyl of A. artus is much more highly specialized than that of A. variiis. In the latter species, when the gonotyl is viewed from the lateral surface it appears as a simple prominence (Fig. 60) without terminal adornments. In both A. variiis and A. artus we have evidence which seems to indicate that the gonotyl is permanently extruded from the body surface and incajjable of retraction within the genital sinus. This is especially well illustrated by A. artus, for in all of our whole Parasites of Oneida Lake l-islics mounts the distinctive form of tlie <(on()tyl shows clearly and gives no evidence of retraction. Serial sections in all three planes have heen studied to determine the nature of the ventro-genital complex in both species of Allacanthochasmus. All of the sections uniformly give evidence that the ducts of both sexes open by a common genital pore through the common genital atrium lying between the submerged ven- tral sucker and the gonotyl. In no instance was there any evidence of direct com- munication between the ductus ejaculatorius and the copulatory apparatus. As discussed under the genus Neochasmus, there is one point wherein Alla- canthochasmus falls short of perfect agreement with current characterizations of the family Heterophyidae. and this is in regard to the form of the ovary. The transverse band of finely divided ovarian follicles is not a wide departure from the lobed ovary of the other heterophyids. This becomes especially obvious when developmental stages are studied. The ovary of A. artus is not so minutely divided into follicles as is that of A. varius, and we have before us some immature speci- mens of A. artus in which the ovary consists of as few as three lobes. Thus in Allacanthochasmus, ontogeny j)resents the direct evidence of continuity of the follicular and lobed ovary, for one develops into the other during the lifetime of a single individual. According to some of the early treatises on the Heterophyidae (Ransom, 1920) the uterus is described as wholly pre-testicular. As pointed out earlier in this paper, later workers have found that uterine development may show extreme variation even within members of the same genus, and consequently this as a lim- iting character has been omitted from more recent family diagnoses. Accordingly, the extent of the uterus into the posterior extremity in Allacanthochasmus does not discredit the more significant evidences favoring inclusion of this genus in the Heterophyidae. In sagittal and in cross sections of both species of Allacanthochasmus, the dorsal lip of the oral sucker shows a distinct thickening. On living specimens, this lip overhanging the dorsal edge of the mouth, has frequently been observed as a slight protrusion from the mouth cavity. This condition was not mentioned in the original description of A. varius, for its significance was not then understood, but now it furnishes another point of definite agreement with the condition described for some other heterophyids. The foregoing evidences provide ample grounds for the inclusion of Allacan- thochasmus in the Heterophyidae. The proposal of Poche (1926:165) to place this genus in the Acanthostomidae seems wholly indefensible on the grounds of the new evidences here summed up for the first time. Life cycle All of the available evidence indicates that the metacercariae of the avian and mammalian heterophyids become encysted in the flesh of fishes after undergoing their parthenogenetic generation in the body of a snail. The complete life history is not known for a single one of the seven genera of fish trematodes discussed in the foregoing synopsis. However, the encysted young of Allacanthochasmus have been found repeatedly in the tissues of fishes which never serve as normal hosts of 132 Rooscrclt Wild Life Annals the adult flukes. Intact cysts and excysted worms have been removed from the lumen of the digestive system of the same fish host, and in several instances frag- ments of fish still holding encysted worms were found among the freed cysts. These observations corroborate the supposition that the definitive fish host acquires its heterophyids through the agency of an alternative fish host, as in the avian and mammalian representatives of the Heterophyidae. SECTION 4. FAMILY RELATIONSHIPS OF THE GENUS MICRO- PHALLUS WARD, 1901 (Figures 39 to 43) The position of the genus Microphallus in the system of trematodes has been the subject of prolonged debate. Ward (1901), in the original definition of the genus, recognized it as representing a previously unknown subfamily to which he gave the name Microphallinae. Subsequent workers have expressed many diver- gent opinions as to the proper allocation of this subfamily. It seems entirely prob- able that some genera have been added to the subfamily on the basis of superficial resemblances, but without due consideration to fundamental morpholo;,ncal agree- ment. The type genus alone has been studied in detail. Ward (1901) and Wright (1912) have presented the details of morphology of the type species M. opaciis in very satisfying details, but isolated observations on other genera have supplied a thin thread of evidence which has been woven into a bond of subfamily unity by other workers interested in establishing the relationships of some other genera which have been ascribed to the Microphallinae. \Vitenberg has stated that some members of the Microphallinae are provided with a cirrus pouch. If this struc- ture is present in a given genus, it seems to the writers that this fact alone is the best sort of Iirief for the exclusion of that genus from the Microphallinae. No structure even remotely resembling a cirrus pouch is present in members of the type genus of this sulifamily. It seems highly probable that the genera which have come to be considered as related to Microphallus, form, in reality, a composite group not representing a homogeneous subfamily. For this reason, in the present discussion of relationships of the subfamily, attention will be restricted to a consid- eration of conditions found in the type genus. Some one should restudy the entire group of genera which have been assumed to stand near to Microphallus. Little is to be gained from a reconsideration of the confusing and incomplete descriptions available for these forms in the literature. The new study should be based upon specimens, not upon faulty concepts. Some measure of the wide disagreement concerning the location of the Micro- phallinae may be gained from a brief review of the literature. There have been two distinct schools of writers on this subject. One of these has maintained that the subfamily belongs within the Heterophyidae, and the other has adopted the alternative of excluding it, but with diverse solutions as to where it really belongs. Odhner (1911), NicoU (1924), Poche (1926) and Fuhrmann (1928) have expressed the definite opinion that the Microphallinae are a subfamily of the Heterophyidae. Stunkard (1929) has shown that the excretory system of Micro- phallus is more nearly like that of the heterophyids than is that of Cryptocotyle — Parasites of Oiicida Lake I'ishcs 133 a genus very generally admitted as a heterophyid in good standing. However, the indeterminate results of such a study of a single organ system are reflected in the following quotation from Stunkard (1929:265): "If the form of the excretory system is used as the criterion for determining relationships, Microphallus rather than Cryptocotyle should he retained in the family." But in the same paragraph he had previously stated that "The removal of Microphallus from the family Heterophyidae may perhaps be advocated, but the exclusion of Cryptocotyle, I believe, will be hard to justify." Somewhat comparable indecision is voiced by Faust (1929:90) who makes no definite assignment for the Microphallinae, though he tentatively places them in the superfamily Heterophyoidea pending further information regarding the life history. Opposed to the foregoing point of view stands the united opinion of Ransom (1920), Ciurea (1924), Travassos (1920), Viana (1924) and Witenberg (1929) who either by definite statements rule the Microphallinae out of the Heterophyidae or tacitly do so by failing to make mention of this subfamily in their respective systems of the heterophyids. Witenberg (1929:137) states very definitely that "The genera united in the subfamily Microphallinae Ward, 1901, do not belong to the Heterophyidae, since they lack a seminal receptacle and some of them are provided with a cirrus pouch." After a careful study of four species belonging to the genus Microphallus, the present writers are, in principle, in accord with Witenberg's elimination of the members of this genus from the Heterophyidae, but their reasons are somewhat dififerent from those advanced by Witenberg. In the first place, no member of the genus which has come to our attention is provided with a cirrus pouch. The copulatory organ in all members of this genus agrees with the general plan of copu- latory papilla such as was originally described by Ward for the type of the genus. This copulatory organ (Figs. 39 and 40, p) m all members of the genus consists of a thickening of the terminal portion of the ductus ejaculatorius. This organ is not supplied with a cirrus pouch nor is it on the other hand to be confused with the gonotyl found in many of the heterophyids. So distinctive is this type of cirrus in Microphallus that any genus or species having a cirrus pouch could not be con- sidered as belonging to the same family and must be excluded from the Micro- phallinae. At the same time the cirrus of the true Microphallinae is so distinctly different from the copulatory apparatus of the heterophyids that on this fact, with the lack of a seminal vesicle and the nature of the genital pore as contributory, we base our argument for sharp separation of Microphallinae from Heterophyidae. In every one of the seven genera ascribed to the Heterophyidae in this paper, the ducts from the gonads open into the genital sinus by way of a common genital duct. There is thus a single genital pore in all of the Heterophyidae of fishes dis- cussed in this report. Contrary to this arrangement stands the condition found in Microphallus (see Plate 22) wherein the two genital ducts open independently in a shallow genital sinus (Figs. 39 to 42). Ward (1901) made detailed studies of the male genitalia of M. opacus and was able to secure specimens fixed in copula, so there can be no doubt as to the functional relations of the cirrus and the genital pore. The present writers have studied the same species and in addition have investigated M. ovatus (Plate 22) 134 Roosez'clt Wild Life Aiuuils wherein the cnpulatory organ was found to be in intimate agreement with Ward's description of AI. opacits. In two other species which the present writers have described from fishes of Oneida Lake, New York, the general topograjjhy of the genital organs is the same, but the seminal vesicle is highly modified and the copu- latory papilla is much more elongated than in M. opacus and M. ovatus. All four of the species that have been investigated bear out the conclusion that the Micro- phallinae stand as a sharply isolated group. Travassos (1920) elevated the Microphallinae to family rank and in this was followed by Viana (1924). In this elevation, the present writers concur. The genus Microjihallus is distinctly and incompatibly diflferent from the Hetero- phyidae. The degree of separation warrants the recognition of a family Micro- phallidae to include the genus Microphallus. Until the detailed morphology of Levinseniella, Spelotrema, Spellophallus, Monocaecum, and Maritrema has been determined as compatible with that of Microphallus, these genera should be excluded from the Microphallidae, though Poche (1926:151) has attempted to relate them to the subfamily Microphallinae. Parasites of Oneida Lake fislies 135 LITERATURE CITED Baer, J. G. 1931. Quelques Helniintlies rares ou peu coniuie du Putois. Rev. Suisse de Zool., Tome 38, Fasc. 2, pp. 313-334. Bangham, R. V. 1926. Parasites other than cestodes in black bass of Ohio. Ohio Jour. Sci., Vol. 26, pp. 117-127. Baylis, H. a., and Dambney, R. 1926. A synopsis of the families and genera of Nematoda. Firitish Museum, London. Bychowsky, B. 1931. Neue Dactylogyrus Arten aus dem Aralsee. Zool. Anz., Bd. 95, nr. 9/10, pp. 233- 240. Ciurea, I. 1924. Heterophyides de la faune de Roumanie. Parasitol., Vol. 16, pp. 1-21. Cooper, A. R. 1915. Trematodes from marine and fresh-water fishes, including one species of ectopara- sitic turbellarian. Trans. Royal Society Canada, Ser. Ill, Vol. 9, pp. 181-205. 1918. North American Pseudophyllidean cestodes from fishes. Illinois Biol. Monogr., Vol. 4, no. 4, pp. 1-234. Faust, E. C. 1929. Human Helminthology. Lea and Febiger, Philadelphia. Fuhrmann, O. 1928. Zweite Klasse des Cladus Plathelminthes, Trematoda. In Kiikenthal's Handbuch der Zoologie, Bd. 2, Lief. 3. GuBERLET, J. E., Hansen, H. A., and Kavanagh, J. A. 1927. Studies on the control of Gyrodactylus. Pubis, in Fisheries, Univ. Washington, College of Fisheries, Vol. 2, no. 2, pp. 17-29. Hess, W. N. 1928. The life history and control of Dactylogyrus sp. Jour. Parasitol., Vol. 15, no. 2, p. 138. 1930. Control of external fluke parasites on fish. Ibid., Vol. 16, no. 3, pp. 131-136. Holl, F. J. 1928. Two new species of parasites. Jour. Elisha Mitchell Sci. Soc., Vol. 43, pp. 184-186. Hughes, R. C. 1927. Studies on the trematode family Strigeidae (Holostomidae) , No. VI. A new meta- cercaria Ncasciis ambloplitis sp. nov., representing a new larval group. Trans. Amer. Micros. Soc, Vol. 46, no. 4, pp. 248-268. 1928a. Studies on the trematode family Strigeidae (Holostomidae), No. IX. Neascus van-clcavei (Agersborg). Ibid., Vol. 47, no. 3, pp. 320-341. 1928b. Studies on the trematode family Strigeidae (Holostomidae), No. X. Neascus bulboglossa (Van Haitsma). Jour. Parasitol., Vol. 15. pp. 52-57. Hughes, R. C, and Piszszek, F. R. 1928. Studies on the trematode family Strigeidae (Holostomidae), No. XI. A^cascus ptychocheilus (Faust). Ibid., Vol. 15, pp. 58-62. Hunter, W. S. 1928. A new strigeid larva, Neascus ivardi. Ibid., Vol. 15, pp. 104-114. KULWIEC, Z. 1927. Untersuchungen an Arten Genus Dactylogyrus, Diesing. Bull. Acad. Polonaise d. Sci. et Lett., pp. 114-144. Looss, A. 1896. Recherches sur la faune parasitaire de I'Egypte. Mem. Inst. Egypt, \'oI. 3, pp. 1- 252. 1896a. Notizen zur Helminthologie Aegyptens, I. Centralbl. Bakt., Bd. 20, pp. 863-870. 1899. Weitere Beitrage zur Kenntniss der Trematoden-Fauna Aegyptens, zugleich Ver- such einer natiirlichen Gliederung des Genus Distomum Retzius. Zool. Jahrb, Abt. f. Systemat., Bd. 12, pp. 521-784. 136 Rooscz'clt Wild Life Annals Li- HE, M. 19()9. Parasitische Plattwiirnier, 1 : Treinatodes. Brauer's Siisswasserfauna Deutschlands. Heft 17. McCallum, G. a. 1915. Some new species of ectoparasitic treniatodes. Zoologica (N. Y.), Vol. 1, pp. 393-407. McC.M.LUM, W. G. 1895. On the anatomy of two distome parasites of freshwater fish. Veterin. Mag., Vol. 2, pp. 1-12. Mac..\th, T. B. 1917. The morphology and life-history of a new trematode parasite, Lissorchis jairporti, nov. gen, et nov. sp., from the buffalo fish, Ictiobus. Jour. Parasitol., Vol. 4, pp. 58-69. Marshall, W. S., and Gilbert, N. C. 1905. Three new trematodes found principally in black bass. Zoolog. Jahrb., Bd. 22, pp. 477-488. Nicoll, W. 1909. Studies on the structure and classification of the digenetic trematodes. Quart. Jour. Micros. Sci.. Vol. 53, pp. 391-487. 1924. A reference list of the trematode parasites of British freshwater fishes. Jour. Parasitol., Vol. 16, pp. 127-144. Nybelin, O. 1924. Dactylogynis vastator, n. sp. Arkiv Zoologi, Bd. 16, pp. 1-2. Odhner, T. 1911. Zum natiirlichen System der digenen Trematoden IV. Zool. Anz., Bd. 38, pp. 513-531. Osborn, H. L. 1903. On Crvptogoniinus (n. g.) chvH (n. sp.) a f.uke with two ventral suckers. Zool. Anz.," Bd. 26, pp. 315-318. Pearse, A. S. 1924. Observations on parasitic worms from Wisconsin fishes. Trans. Wisconsin Acad. Sci., Arts, Letters, Vol. 21, pp. 147-160. 1924a. The parasites of lake fishes. Ibid., Vol. 21, pp. 161-194. POCHE, F. 1926. Das System der Platodaria. Arch. f. Naturg., Bd. 91, pp. 1-458. Pratt, H. S. 1923. Preliminary report on the parasitic worms of Oneida Lake, New York. Roosevelt Wild Life Bull., Vol. 2, no. 1, pp. 55-71. Ransom, B. H. 1920. Synopsis of the trematode family Heterophyidae with descriptions of a new genus and five new species. Proc. U. S. Nat'l Museum, Vol. 57, pp. 527-573. SiMER, P. H. 1929. Fish trematodes from the lower Tallahatchie River. Amer. Midland Nat., Vol. 11, no. 12, pp. 563-588. SiNITSIN, D. 1931. Studien fiber die Phylogenie der Trematoden. IV. The life histories of Plagioponis silicuhts and Plagioponis virens with special reference to the origin of the Digenea. Zeitschr. f. wissensch. Zool., Bd. 138, pp. 409^56. Skinker, M. S. 1931. A redescription of Cystidicola stigiitatura (Leidy), a nematode parasite in the swim bladder of salmonid fishes and a description of a new nematode genus. Trans. Amer. Micros. Soc, Vol. 50, no. 4, pp. 372-379. Stafford, J. 1900. Some undescribed trematodes. Zool. Jahrb., Bd. 13, pp. 3';9-414. 1904. Trematodes from Canadian fishes. Zool. Anz., Bd. 27, pp. 481^95. 1905. Trematodes from Canadian vertebrates. Ibid., Bd. 28, pp. 681-694. Parasites of Oneida Lake Fishes 137 Stunkard, H. W. 1929. The excretory system of Cryptocotylc (Heteropliyidae) . Jour. Parasitol., Vol. 15, no. 4, pp. 259-266. TRAyAssos, L. 1920. Contribuicoes para o conheciiiiento do fauna liclinintologico brasileira XI, Arcli. Esc. Sup. Agr. & Med. \'et., Tom. 4, p. 85. 1930. Revisao do genero Ascocotyle Looss, 1899 ( Treniat(xla : Heterophyidae) . Mem. Inst. Oswaldo Cruz, Tom. 23, pp. 01-79. Van C'LEAyE, H. J. 1921. Notes on two genera of ectoparasitic trematodes from fresh-water fishes. Jour. Parasitol., Vol. 8, pp. 33-39. 1922. A new genus of trematodes from the white bass. Proc. U. S. Nat'l Museum, \'ol. 61, art. 9, pp. 1-8. Van CLEAyE, H. J., and ^vIueller, J. F. 1931. The systematic position of some trematodes from fresh-water fishes of North America. Jour. Parasitol., Vol. 18, no. 2, p. 132. 1932. Parasites of the Oneida Lake fishes, Part I. Descriptions of new genera and new species. Rooseyelt Wild Life Annals, Vol. 3, no. 1, pp. 1-72. VlANA, L. 1924. Tentatiya de catalogacjo das especies brazileiras de trematodeos. Mem. Inst. Oswaldo Cruz, Tom. 17, fasc. 1, pp. 95-227. Ward, H. B. 1894. On the parasites of the lake fisli. L Notes on the structure and life history of Distoma opacum, n. sp. Proc. Amer. Micros. Soc., Vol. 15, pp. 173-182. 1901. Notes on the parasites of the lake fish. III. On the structure of the copulatory organs in Microphallus nov. gen. Ibid., \o\. 22, pp. 175-187. 1907. Iconographia parasitorum hominis. Lincoln, Nebraska. Ward, H. B., and Mag.\th, T. B. 1917. Notes on some nematodes from fresh-water fishes. Jour. Parasitol., Vol. 3, pp. 57-64. Ward, H. B., and Whipple, G. C. 1918. Fresh-water biology. Wiley, New York. Witenbejrg, G. 1929. Studies on the trematode family Heterophyidae. Ann. Trop. Med. and Parasitol., Vol. 33, no. 2, pp. 131-239. 1930. Corrections to my paper "Studies on the trematode family Heterophyidae". Ann. and Mag. Nat.' Hist., Ser. 10, Vol. 5, pp. 412-414. Wright, S. 1912. Notes on the anatomy of the trematode Microphallus opacits. Trans. Amer. Micros. Soc, Vol. 31, pp. '167-175. YoRKE, W., and Maplestoxe, P. A. 1926. The nematode parasites of vertebrates. Blakiston, Philadelphia, Pa. TRICHODINA REN ICO LA (MUELLER, 1931), A CI LI ATE PARASITE OF THE URINARY TRACT OF ESOX NICER Bv Justus F. Mueller, Field Natitralist. Roosez'clt Wild Life Station CONTENTS Introduction 139 Systematic position of T. rcnicola 140 Urceolariidae previously described 140 Anatomy of Trichodina rcnicola 142 Comparison with other species 144 Binary fission in T. rcnicola 144 Technique 145 Host relationships 145 Pathology 145 Transmission of the parasite 146 Summary 148 Bibliography 154 INTROPUCTION On numerous occasions the chain pickerel {Esox niger), in Oneida Lake, has been found to bear in its urinary tract a peritrichous cihate which was at first taken to be a species of Cyclochaeta, and named Cyclocliaeta renicola. The name, with a brief description, was pubhshed in an abstract in the Journal of Parasitology, December, 1931, in the section "Abstracts of Papers Contributed for the Seventh Annual Meeting of the American Society of Parasitologists, New Orleans, La., December 29, 30, and 31, 1931". It was originally planned to present a paper on this parasite before the meetings of the Society, but at the last moment the author was unexpectedly prevented from attending, so that the paper was not read. Subsequent study of the protozoan has disclosed the fact that in the original description it was erroneously allocated in the genus Cyclochaeta, but belongs properly in the closely related genus Trichodina. Its correct name therefore becomes Trichodina renicola (Mueller, 1931). The present paper gives a more extended description of this parasite, with a discussion of its systematic position, and its host relationships. [139] 140 Rooscrcll Wild Life .huials SYSTEMATIC POSITION OF T. RENICOLA Tile .n'cmis '["richodina is a natural relative of twd cluselv similar <4"enera, Cyclo- ehaeta and rrccolaria. There is no general agreement concerning the exact sys- tematic position of these forms. Fulton, 1923. following the example of Wallen- gren, 1897, unites the three genera in the family Urceolariidae of Stein. The Urceolariidae. according to this classiiication, form the third family of the Order Peritrichida. Calkins, 1926, on the other hand, reduced the group to suhfamily rank, the Urceolariinae, under the family V'orticellidae, following Doflein and JMinchin. This disposition of the group is, however, ohjectionahle. The Urceolariidae form a natural group sufficiently well characterized and set off to justify their receiving equal rank with the \'orticellidae. Furthermore, discrepancies appear in Calkins' key. ( )n page 411, under Peritrichida, at 2, he has as second alternative "Not l^arasitic, posterior end not flexible — Family 3. \'orticellidae." He then places under the family Vorticellidae the subfamily Urceolariinae, made up almost entirely of parasitic forms. Moreover Calkins suppresses the genus Urceolaria, prol)ably with the idea that it is synonymous with Cyclochaeta. This also seems unwar- ranted, since, as described by various authors, Urceolaria is clearly set oft' from Cyclochaeta by the absence of hooks from the corona. Kudo, 1931, also omits Urceolaria and places the two genera Cyclochaeta and Trichodina in the family Trichodinidae, Claus, making this the first family of the Peritricha. Inasmuch as the genus Urceolaria has distinctive skeletal features, it seems more logical to retain it as a separate concept. For this reason the system followed by Fulton, 1923, still seems to be the best. This is given here. Family Urceolariidae, Stein (3rd family of Peritrichida) . Genus Urceolaria: With a ring of cirri anterior to posterior girdle of cilia, and without hooks on the denticulate ring. Genus Gyclocluiela : Like Urceolaria. but with hooks on the denticulate ring. Genus Trichodina : Like Cyclochaeta, but without cirri. In this analysis I omit the characters of the peristome given by Fulton, 1923. These are not constant for the genera and when used in a key result in confusion. The reader is referred to Fulton's paper, which gives an excellent review of the family, and an account of Wallengren's fundamental work, published in Swedish, and hence inaccessible in the original to most English-speaking zoologists. URCEOLARIIDAE PREVIOUSLY DESCRIBED A number of dift'erent Urceolariidae have been described. With the exception of the Trichodina reported by Rosseter and Fulton from the urinary tract of amphibia, most of them live as ectoparasites, or ectocommensals, on the surface of various animals. Only a few of them will be mentioned here. rarasitcs of Oneida Lake Fixlics 141 A review of the different species is given by Fulton, l'^23, and a number are also mentioned l)y Reynolds, 1930. Many of the Triehodina reported have been found, or sus])ected to be, synonymous with 'frichod'nia pcdicitlus Ehrenberg. In com])an\' with several other Trichodinae this species is a])parently without any definite host specificity, and has been reported from such widely different sources as the skin and gills of urodele larvae, and the surface of fresh-water hydroids. Fulton, 1923, described another species, T. itriiiicola, from the urinary bladder of a toad. Fulton recognized this species as the same as one which Rosseter, 1886, had described from the kidneys, urinary l)ladder, urinary ducts, and testes of Triton crisfatus. Structurally this species is close to 7\ pcdicitlits. but Rosseter showed that the T. pcdicidus from the surface and gills of am])hibians would very readily infect Hydra, proving its identity with 7\ pcdicitlits; whereas the form from the bladder could not l)e induced to infect the polp, but recoiled from it. The generic allocation of several of the Urceolariidae is in flux. Thus l<\ilton lists I'rceolaria mitra (von Siebold), from planarians ; Urceolaria patellae Qienot, from gills of moUusca ; Cyclochaeta scorpciiae Fab.-Dom., from gills of fish; and Cyclochaeta synaptae Cuenot, from echinoderms. Whereas Reynolds, 1930, refers to all these species as Triehodina. There is, however, no adequate reason for this simplification, and until further studies are made Fulton's usage should be followed. Cyclochaeta doiiiergitei W'allengren has been reported from European fish. Frequent references to Cyclochaeta occur in the literature of fish culture, usually without any designation of species. It is doubtful in most cases whether the material dealt with is Cyclochaeta or Triehodina, for in ordinary observation the difference between the two would ])rob^bly not be noticed. Plehn, 1924, refers to several Cyclochaeta encountered in fish culture in Germany, giving diameters and number of hooks in the horny ring. In her description she mentions "Ein Kranz langer W'impern, . . . ausserdem sind plumpere, breitere Cirrhen vor- handen." In her drawing, however, there is no indication of a row of cirri, and the posterior crown of cilia is erroneously made to turn in at one side after the fashion of the adoral spiral. Hofer, 1904, on the other hand, reports Cyclochaeta on fish in Germany, and gives a figure (after Moroff) of C. doinerguei^ in which the row of posterior erect setae are correctly shown. Some distance anterior to these ap])ear the cilia of the oral groove. Davis, 1929, mentions Cyclochaeta as occurring commonly on American trout. Fie figures a form with 23 hooks in the denticulate ring, but with no cirri, and in his description he mentions the posterior girdle of cilia and the adoral s])iral. but makes no reference to cirri. Thus if his description is correct the form is a Triehodina. The present writer has collected material from western trout, some- what similar to the form figured by Davis. This species has 29 to 30 hooks in the skeletal ring, and was at first thought to be Cyclochaeta, but after careful study no cirri are discoverable. It is 0.120 mm. in diameter (over twice the diameter of C. domergiici • — 0.055 mm.), and the process of fission and rebuilding of the skeletal ring is similar to that described by Wallengren and Fulton for Triehodina. This species has not been sectioned, and so it is not possible to state with certainty 142 Roosevelt Wild Life Annals that cirri are absent. However, they appear to be lacking in ol)servation of the entire animal, and in all probability this is a species of Trichodina, ectoparasitic upon trout, which has hitherto been mistaken for a Cyclochacta. Diller, 1928, published a very excellent paper on binary fission and nuclear phenomena in a species of Trichodina found on anuran tadpoles. He was unable to identify his form with any previously described species, and left it undetermined. In very recent years a number of species of Trichodina have been described from various hosts by Ariake (1929), da Cunha and Pinto (1928), Fantham (1930), and Ibara (1931). With the exception of Trichodina fariai these are either from the exterior of various fishes, or from the urinary system of amphibia. Da Cunha and Pinto's species, Trichodina fariai, was from the intestine of a marine fish from the coast of Brazil, and hence, although endoparasitic in a fish, could not be the same as T. renicola. Fantham described a number of species ectoparasitic on South African fishes, and one from the urinary system of a toad. Ariake lists a number of new- species from goldfish in Japan. Ibara's species was from the urinary bladder of a salamander in Japan. None of these could be synonymous with T. renicola from Esox niger in Oneida Lake. T. renicola cannot be identified with any previously reported form known to the writer, but in general aspect it comes closest to the form worked on by Diller. From this it differs in certain respects which will be emphasized later on. ANATOMY OF TRICHODINA RENICOLA This species occurs as an endoparasite in the urinary bladder and ureters of the pickerel, Esox niger, in Oneida Lake. The anterior surface (the side away from the sucking disc) is strongly arched, but less so than in most other species of Trichodina. There is no suggestion of the hour-glass shape of T . pedictdus, or of the barrel-shape of T. urinicola. Normally T. renicola has the form of a small hemisphere (Figs. 2, 3, 8), with a diameter of about 0.080 mm. Small specimens have been observed which were only 0.070 mm. in diameter, and large ones as much as 0.096 mm. The adoral s])iral of cilia, or peristome, consists of a well defined groove passing m a helix around the anterior surface in a right handed direction. The axis of this helix corresponds to the vertical axis of the animal. Two rows of long cilia spring from the edges of the adoral groove. At their ])ases these cilia are fused so as to form two continuous ])arallel membranelles. At their distal ends, however, the cilia are free. At its lower (outer) end the adoral groove makes a sharp turn and swings into the vestibulum. As it descends into the vestibulum, the ciliated groove makes a complete spiral circuit of its wall. The meml)ranelles pass along the groove clear to the bottom of the vestibulum. The gullet arises from the bottom of the vestibulum at a slight angle, and passes inward toward the center of the animal. A large contractile vacuole lies alongside the vestibulum between the ends of tlie macronucleus. It opens into tlie vestibulum by a connecting duct, which usually shows up very clearly in stained sjiecimens. In other species this vacuole is known to pulsate, sluggishly in T. urinicola, but rapidly, at intervals of 10 to 12 Parasites of ())iciect bristles, or cirri are com])letely lacking, and hence the necessity of transferring the species from Cyclo- chaeta, where it was originallv ])laced, to the genus Trichodina. COMPARISON WITH OTHER SPECIES T. rcnicola ditifers from most species of Trichodina in the more compressed, rounded body form. 7'. pcdiculns, and related types, have a tall body, with the adoral groove forming a large circle on the upper edge, delimiting a flat anterior surface which is even greater in diameter than the sucking disc. They have in general a "flower pot" shape. T. stciiii has a more elevated body with a sharper apex. T. itriiiicola has a pronounced barrel shape, with the top end rounded off. It has a small sucking disc, and greatest diameter in the middle of its height. It is about twice as tall as the diameter of its sucking disc. T. rcnicola comes nearest to Trichodina sp. described by Diller, 1928, on tadpoles. Both species have the same hemispherical shape ; however, Diller's form was much smaller — only 0.035 mm. in diameter — whereas T. rcnicola is about O.OcSO mm. in diameter. T. rcnicola has a larger number of hooks in its denticulate ring than any other species of the I'rceolariidae known to the present writer. T. pcdiciiliis has 24 to 26 denticles in its corona, and the same limit applies to related forms. 7". nrinicola has 28 to 36 hooks in its ring. Diller's Trichodina had 15 to 24 denticles in the corona with 21 as the mode. T. rcnicola, however, regularly has 56 hooks in its ring. In the genus Cyclochaeta the number is usually less than thirty. BINARY FISSION IN T. RENICOLA .•\s is usual in the Urceolariidae, this species reproduces by binary fission, with two offspring of equal size resulting. The skeletal ring divides transversely in the process and the two ends join. For a short time, such young individuals have a corona with only half the normal number of denticles, and the denticulate ring lies near the center of the striated ring. Individuals of this sort were found for 7'. rcnicola, but the subsequent stages in the assumption of the adult condition were not observed. It has been shown, however, in other species, that a second ring of denticles forms dc novo peripheral to the smaller, inherited ring, and this second ring has from the first the normal number of denticles for the species. The writer has observed this i)rocess in the above mentioned sj^ecies of Trichodina ( ?) from the trout. There is no reason to doubt that it is repeated in the usual Parasites of (hic'ula iakc I'islics 145 manner for T. rciiicola. As the now rin<;- assumes the final form the smaller rinj^ is resorbed. Immediately after fission tiie maeronuelens is shorter than in the adult, form- ing scarcely a half circle. It elongates with growth until the final ])r()])ortions are reached. .\ young T. rcnicola, immediately after fission, with a short macronucleus, and half the normal number of denticles in its corona, is shown in figure 5. The new ring of denticles has not yet begun to form. TECHNIQUE The material forming the basis of this study was fixed by opening infected bladders and dropping the contents into hot Bouin's fluid. After washing, the protozoa were stained in Ehrlich's hematoxylin and mounted in toto. Entire blad- ders, known to be infected, were dropped whole into hot Bouin's, and later the contents were removed, or the bladders were sectioned without opening. Pieces of kidney were fixed by various methods, and later sectioned to study the parasites in the ureters. For sections, ordinary hematoxylin and eosin were found to give good differentiation. The corona and striated ring have a strong affinity for eosin and stand out with great clearness after this procedure. Other authors have tried fixing smears on slides and staining as in blood work, but this procedure did not appear necessary or suitable for purposes of this study, and was not used. HOST RELATIONSHIPS T. rcnicola appears to be very specific for its host, Esox niger. So far, the parasite has been observed only incidentally, while making a survey of helminth parasites. After the date of initial discovery, December 26, 1930, twelve pickerel were examined at different times up to the present date, and only two failed to harbor the organisms. The closely related Esox luciiis, however, was not infected, even when taken from the same habitat and in the same net with infected Esox niger. Outwardly the infected fish appeared normal. The intensity of the infection varies from a sparse population of Trichodina at the neck of the urinary bladder, to a very heavy bladder infection in which the protozoa are literally swarming. When such a bladder is opened, the contents have a creamy appearance due to the enormous numbers of Trichodina present. In such heavy infection the ureters and kidneys are found to be involved. The parasites invade the ureter and its branches, ascending these ducts as far as possible until the diameter of the tubes becomes too small to allow further ascent to the Trichodinae. In sections they can be seen at times literally packed in the ureters, not only lining the walls, but lying on top of each other and free in the lumen of the tube. PATHOLOGY Little is known about the pathological effects of Trichodina or Cyclochaeta infection. In very heavy infections of small fish, Cyclochaeta may cause the death of the host. Hofer states that their presence in large numbers causes an inflamma- 146 Roosc7rlt Wild Life Annals tion of the mucous epithelium, with overproduction of shme, sloughing of cells, and the appearance of inflamed or cloudy patches. Several factors may enter to i)ro- duce injury to the host. In the first place, the mere presence of such forms in numbers on the gills or integument may interfere with gaseous exchanges to such an extent as to cause suffocation of the host. In the second place, substances may be given off by the Trichodinae which have a toxic effect upon the host. In the third place, a certain amount of direct injury is probably done to the host epithelium by the action of the sucking disc of the parasite. The exact extent of this mechani- cal injury is uncertain, but, it would appear that Trichodina is capable of consid- erable power of suction. Hofer states that due to the action of Cyclochaeta, groups of epithelial cells are gradually loosened and dislodged. In sections of bladders and kidneys of Esox, with Trichodina, the Trichodinae are seen in many cases closely applied to the epithelial wall. The sucking disc can be very strongly acti- vated, the protoplasmic plug, which passes through the center of the exoskeleton, being drawn upward after the manner of a piston, lifting the inner edge of the skeletal ring with it. In this manner a deep sucking cup is formed and the body assumes the shape of a bell. Animals with this shape can be seen applied to the walls of the urinary tract, with the epithelium bulging upward into the bell. The edge of the sucker fits into a deep groove in the host tissues. Whether this effect is the result of sucking action, or whether such animals merely chanced to settle down upon a convenient elevation of the epithelial wall cannot be stated. However, definite areas of laceration and desquamation of the epithelial cells can be found which can only be attributed to the mechanical effects of the parasite, and at times clumps of such dislodged and disintegrating epithelial cells lie free in the lumen of the ureter. The glandular part of the kidney appears normal, the size of the Trichodinae preventing the parasite from entering the tubules. There would appear to be some possibility of blockage of the ureter from the large number of parasites present, but if this ever occurs it has not been observed. Fulton was inclined to attribute the moribund condition of a toad found infected with T. urinicola to the presence of the enormous numbers of the parasites in the urinary bladder. In spite of the occurrence of mechanical damage to the urinary epithelium of the host in T. renicola infection, the amount of injury does not seem sufficient to cause serious consequences. However, it is possible that toxic products given off by the parasites are absorbed by the host with detrimental effects. Nothing is known about this aspect of the problem. Diller noted that tadpoles bearing a heavy infection of Trichodina on their outer surfaces were smaller than tadpoles with a light infection. He was hesitant, however, about attributing any stunting effect to the presence of the parasite. Upon superficial examination, infected kidneys and bladders appeared normal. TRANSMISSION OF THE PARASITE Since both external and endoparasitic forms of Trichodina are known the transmission of the organism from fish to fish would appear to be capable of easy explanation. A brief period of ectoparasitic existence with transfer and resumption of the endoparasitic habitat through the cloaca, would seem to be a Parasites of Oneida Lake Fishes 147 plausilile hypothesis. Actually, however, tiie prohleni is prohahly not so easy. Nearly all the endoparasitic protozoa offer prohlenis in the (juestion of their trans- mission, which seem opposed to a simple solution. Rosseter, 1886, demonstrated conclusively a difference in reaction between closely similar Trichodinae living on the outside of and within the urinary bladder of Triloii eristatiis. The ectoparasitic species was shown to be the same as T. pedicidus, commonly infecting Hydra as an ectocommensal. The endoparasitic form, however, did not live upon the external surface of its salamander host, and recoiled from Hydra. This latter species is regarded by Fulton, 192.^, as identical with his T. iirinicola. Fulton found T. iirinicola incapable of living outside the urinary bladder of its host. It is an endoparasitic organism, apparently unable to establish even a brief external residence. He further mentions that numerous other amphibians which had been kept in the same aquarium with the infected toad were found negative. If the parasite were easily transmitted one should expect that under close proximity all of the associated animals would have become infected. The fact that they were not could not be attributed to host specificity, for this Trichodina, also reported from Triton cristatits, would appear to have a wide choice of hosts. Careful search has so far failed to reveal any Trichodina living ectoparasitic- ally upon pickerel infected with T. renicola. When removed from the bladder into lake water the life of the organism is very brief. It swims about actively for a short period, but rapidly swells up (endosmosis ?), and within two or three minutes dies and disintegrates. That the parasite does pass from fish to fish, and very efficiently, however, is indicated by the high incidence of infection in pickerel in Oneida Lake. No other Trichodina has been found by the author in Oneida Lake, and numerous examinations of fish gills for ectoparasites have failed to reveal either this genus or Cyclochaeta. That T. rcnieola is wndely distributed in Oneida Lake, however, is shown by the finding of infected pickerel at both ends of the lake — in Big Bay, and Fish Creek, twenty miles apart, as well as in the Cleveland harbor, in about the center of the north shore of the lake. A study of all phases of this disease is planned in the near future. Trichodina rcnlcohj appears to be the first species of the family reported from the urinary system of a fish. It offers a close parallel to the form found in the urinary tract of Amphibia, and extends this type of parasitism into another Class of the Vertebrates. T. renicola, however, is unique in its narrow host specificity. Although hundreds of fish, of about thirty different species, from Oneida Lake, have been examined by the present writer for parasites, Trichodina has never been found in any except Esox nigcr. This is quite a contrast to the habits of 7\ iirinicola, which apparently infects indifferently a number of diverse species of amphibians. Diller, likewise, found his Trichodina abundantly present on all species of tadpoles examined. A slide containing numerous stained specimens of T. renicola has been deposited in the U. S. National Museum, as cotype material of the species. 148 Rooscrclt Wild IJfc .liiiials SUMMARY 1. Cyiiocliacta rcnicola Mufller, is rcnidvcd to the <^enus Trichodina. 2. The species is descrihed. It ajipears to be a valid form, differing from others jireviously rejiorted in the large number of denticles (56) in its corona, as well as in other characters. 3. The parasite is fonnd in the urinary system of Esox iiiger, causing some mechanical injury; but apparently no serious consequences result to the host. 4. This is the first Trichodina described from the urinary tract of fish. 5. r. rcnicola differs from 'J\ uriiiicola, reported from the urinary tract of various amphibia, in its specificity for a single host, E. nigcr. This fish is generally infected in Oneida Lake. 6. The mode of transmission of the ])arasite is unknown. 150 Roosc7'clt Wild Life .liiiials Plate 26. Superticial anatomy of T ricliodiiia rciiicola. Fig. 1 : Cross section of ureter of Esox nigcr, showing Trichodina in lumen and attaclied to wall. The surrounding kidney tissue not shown. Fig. 2: Cluster of Trichodina as removed from wall of infected hladder, after bladder was fixed whole. The parasites are so abun- dant that they crowd each other closely for attachment room on the wall of the bladder, and consequent! \- rest on top of each other several layers deep. Fig. 3 : View of a Trichodina renicola from the side, looking into the concavity of the sucking disc, showing form of the animal and arrangement of the parts. Frequently the parasites are more convex than this specimen. Fig. 4 : View of a specimen from above, looking at the anterior surface. The helical adoral groove shows clearly. Relationship of the macronucleus, gullet, and contractile vacuole to the vestibulum are also shown. Fig. 5 : A young individual just after fission, seen from below. The corona has only lialf the normal numl^er of denticles, and the macronucleus is shorter than in the fully grown specimens. Explanation of plate Figures 3 and 4 drawn free hand. All others with camera lucida and Leitz microscope. Figure 5, with 1/12 oil immersion objective and i6x ocular. Fig. 4, with 1/12 oil immersion objective and 8x ocular. Figure i with 3x objective and i6x ocular. Figure 2 with 6x objective and 8x ocular. Figure 3 with 6x objective and i6x ocular. ao — adoral spiral of cilia b — border ring of sucking disc eu — epithelial wall of ureter g— gullet m — mouth mn — micronucleus niu — muscular wall of ureter Abbreviations n — macronucleus pc — posterior girdle of cilia rb — striated ring, or ring band sr — denticulate ring, or corona t — Trichodina within ureter V — velum vac — contractile vacuole Parasites of Oneida Lake I'islies 151 Pl.ATK 2<) 152 Roosci'clt Wild Life .liiinils Plate 27. Detailed anatomv of Tricliodiiia rciiico'a. Fig-. 6 : Partly diagraniniatic drawing showing the relationship of the ])arts of the exoskeleton. The ujiper arms of the ring hars are cnt away at right to show the shorter bars at the lower level. Ring band partly left out to reveal the corona below. The denticles of the corona are shown partly in surface, and partly in cut-away view, to ex]-)lain their relationship. Fig. 7 : Schematic diagram showing parts of exoskeleton and their arrangement. Fig. 8: Section of Tricliodiiia renicola through vertical axis. The vestibulum with the spirally winding end of the adoral groove shown at right. Somewhat schematic in this region in order to show gullet and vestibulum in same view. Fig. 9: Detail of parts shown in above, drawn from a number of specimens. Fig. 10: View of exoskeleton seen from above. Bars of ringband indicated only as far as edge of corona, except for small sector at left. Actually they should cover entire corona in this view (dorsal), as far as inner ends of the rays. Only 53, instead of the usual 56, denticles in this specimen. All figures drawn with camera lucida and Leitz microscope. Figures 6 and lo, with 1/12 oil immersion objective and i6x ocular. Figure 8, with 1/12 oil immersion objective and Explanation of plate 8x ocular. Abbreviations aa — anterior arm of striated ring bars ao — adoral spiral of cilia b — border membrane of sucking disc g— gullet m — mouth n — macronucleus pa — posterior arm of striated ring bars pc — posterior girdle of cilia peg — groove of origin of posterior girdle of cilia r — hooks and rays of denticulate ring rb — striated ring, or ring band sr — denticulate ring, or corona V — velum ve — vestibulum Parasili's of Oneida Luke Fishes 153 Pl.ATK 27 154 Roosevelt Wild Life .liiiials BIBLIOGRAPHY AkIAKK, Bl'NKICHI. 1929. Five new species of TriclKHlina. Aiinot. Zool. Japan. 12:285-288. Calkins. G. X. 1926. The Biology of the Protozoa. Philadelpiiia. D.\ CuxHA, A. M., and Pixto, Cesar. 1928. 'frichodina fariai. n. sp., cilie peritriche endoparasite de poisson marin. Compt. rend. Soc. de biol. 98 :1570-1.V 1. Davis, H. S. 1929. Care and Diseases of Trout. U. S. Bur. of Fish. Doc. No. 1061. DlLLER, W. F. 1928. Binarv Fission in the Trichodina from Tadpoles. Tour. Morph. and Physiol., 46:521-561. Fabre-Domergue, p. 1888. fitude sur I'organisation des Urceolaires, et sur quelques genres d'infusoires voisin de cette famille. Jour. Anat. et Physiol. 24 :214-260. Fantham, H. B. 1930. Some Parasitic Protozoa found in South Africa, XIII. South African Jour. Sci. 27 :376-390. Fulton, John F. 1923. Trichodina pcdiciihis and a New Closely Related Species. Pruc. Boston Soc. Nat. Hist., 37:1-29. HoFER, Bruno. 1906. Handbuch der Fischrankheiten, 2nd ed., Stuttgart. Ibar.^. Y. l'>31. Trichodina okajimac n. sp., a new species of Trichodina from a salamander. Jour. Elisha Mitchell Sci. Soc, 46:214-217. Kudo, R. R. 1931. Handbook of Protozoology. .Springfield. III. Mueller, J. F. 1931. A New Species of Cyclochaeta from the Ureters and Urinary Bladder of Esox rcticu- latus. (Abstract). Jour, of Parasitol., 18:126. Plehn, M. 1924. Praktikuni der Fischkrankheiten. Stuttgart. Revnolls, B. D. 1930. Ectoparasitic Protozoa. Chapter III, in Hegner and Andrews: Problems and Methods of Research in Protozoology. New York. Rosseter, T. B. 1886. On Trichodina as an endoparasite. Jour. Roy. Mic. Soc, 6 :929-933. Wallengren, H. 1897. Zur Kenntniss der Gattung Trichodina, Ehrbg. Biol. Centralbl., 17:55-65. 1897a. Studier ofver ciliata Infusorier, III. Bidrag till Kannedomen om Fam. Urceolarina Stein. Acta Univ. Lund., torn 33, (pt.) II, (no.) 8. Wright, R. R. 1880. Trichodina parasitic on the gills of Necturus. Amer. Nat., 14:133. THE ROOSEVELT WILD LIFE MEMORIAL As a State Memorial The State of New York is the trustee of this wild life Memorial to Theodore Roosevelt. The New York State College of Forestry at Syracuse is a State institution supported solely by State funds and the Roosevelt Wild Life Forest Experiment Station is a part of this institution. The Trustees are State officials. A legislative mandate instructed them as follows : "To establish and conduct an experimental station to be known as 'Roosevelt Wild Life Forest Experiment Station,' in which there shall be maintained records of the results of the experiments and investigations made and research work accomplished ; also a library of works, publications, papers and data having to do with wild life, together with means for practical illustration and demonstration, which library shall at all reasonable hours be open to the public." [Laws of New York, chapter 536. Became a law May 10, 1919.] As a General Memorial While this Memorial Station was founded by New York State, its functions are not limited solely to the State. The Trustees are further authorized to cooperate with other agencies, so that the work is by no means limited to the boundaries of the State or by State funds. Provision for this has been made by the law as follows : "To enter into any contract necessary or appropriate for carrying out any of the pur- poses or objects of the College, including such as shall involve cooperation with any person, corporation or association or any department of the government of the State of New York or of the United States in laboratory, experimental, investigative research work, and the acceptance from such persons, corporation, association, or department of the State or Federal government of gifts or contributions of money, expert service, labor, materials, apparatus, appliances or other property in connection therewith." [Laws of New York, chapter 42. Became a law March 7, 1918.] By these laws the Empire State has made provision to conduct forest wild life research upon a comprehensive basis, and on a plan as broad as that approved by Theodore Roosevelt himself. Roosevelt Wild Life Bulletin, Vol. 4, No. 1. October, 1926. (Out of print) 1. The Relation of Birds to Woodlots in New York State Waldo L. McAtee 2. Current Station Notes Charles C. Adams Roosevelt Wild Life Bulletin, Vol. 4, No. 2. June, 1927. 1. The Predatory and Fur-bearing Animals of the Yellowstone National Park. Milton P. Skinner 2. Current Station Notes Charles C. Adams Roosevelt Wild Life Bulletin, Vol. 4, No. 3. July, 1927. 1. A Trout Survey of Allegany State Park in 1922. William C. Kendall and Wilford A. Dence 2. A Preliminary Survey of the Fish Life of Allegany State Park in 1921. Thomas L. Hankinson 3. Current Station Notes Charles C. Adams Roosevelt Wild Life Bulletin, Vol. 4, No. 4. July, 1927. 1. The Beaver in the Adirondacks: Its Economics and Natural History. Charles E. Johnson Roosevelt Wild Life Bulletin, Vol. 5, No. 1. March, 1928. (Out of print) 1. A Preliminary Wild Life and Forest Survey of Southwestern Cattaraugus Co.. N. Y. Victor H. Cahalane 2. A Preliminary Report on the Trout Streams of Southwestern Cattaraugus Co., N. Y. Wilford A. Dence Roosevelt Wild Life Bulletin. Vol. 5, No. 2. February, 1929. 1. The Fishes of the Cranberrv Lake Region W. C. Kendall and W. A. Dence 2. The Story of King's Pond F. A. Lucas 3. Its Fish Cultural Significance W. C. Kendall Roosevelt Wild Life Bulletin, Vol. 5, No. 3. September, 1929. 1. The Summer Birds of the Northern Adirondack Mountains Aretas A. Saunders 2. The Summer Birds of the Adirondacks in Franklin County, N. Y. Theodore Roosevelt, Jr., and H. D. Minot (Reprinted: original date of publication, 1877) Roosevelt Wild Life Bulletin, Vol. 5, No. 4. August, 1930. 1. The Biology of the Voles of New 'York Robert T. Hatt 2. The Relation of Mammals to the Harvard Forest Robert T. Hatt Roosevelt Wild Life Bulletin, Vol. 6, No. 1. March, 1931. 1. A Biological Reconnaissance of the Peterboro Swamp and the Labrador Pond Areas. Charles J. Spiker Roosevelt Wild I^ife Annals, Vol. 1, Nos. 1 and 2 (Double Number). October, 1926. (Out of print) 1. A Study of the Beaver in the Yancey Region of the Yellowstone National Park. Edward R. Warren 2. Notes on the Beaver Colonies in the Longs Peak Region of Estes Park, Colorado. Edward R. Warren Roosevelt Wild Life Annals, Vol. 1, Nos. 3 and 4 (Double Number). April, 1928. 1. The Ecology and Economics of Oneida Lake Fish. Charles C. Adams and T. L. Hankinson Roosevelt Wild Life Annals, Vol. 2, No. 1. January, 1929. 1. The Red Squirrel: Its Life History and Habits, with Special Reference to the Adirondacks of New York and the Harvard Forest R. T. Halt Roosevelt Wild Life Annals, Vol. 2, No. 2. October, 1929. 1. The Ecology of Trout Streams in Yellowstone National Park. Richard A. Muttkowski 2. The Food of Trout Stream Insects in Yellowstone National Park. Richard A. Muttkowski and Gilbert M. Smith Roosevelt Wild Life Annals. Vol. 2, Nos. 3 and 4 (Doul)le Number). January, 1932. 1. Ornithology of the Oneida Lake Region: With Reference to the Late Spring and Summer Seasons Dayton Stoner Roosevelt Wild Life Annals, Vol. 3, No. 1. January, 1932. 1. Parasites of the Oneida Lake Fishes. Part 1. Descriptions of New Genera and New Species Harley J. \^an Cleave and Justus F. Mueller