is eh oO) bees est ' i haath 4D X Ae etd i ae dag Hah OY aeTe 5 t)3if be ye Meas i “iP SS' oS sae 4 ’ 4 ee Hi ws) ” 3% cide aye tif = Sete te Sere ah : isa baanaees eye) ied a dupierdnes shitdieees is ine int eit sitita Reser ttasealreate vi eran rina es: eed ft PN) if} fae eyias 2 RGs ai sanee ab ied fe rf te eo ated: & CTW wR) late Aiton Cit) aaa M3 atta edt rae Pa ” rr risa a ts eee ite i) ty 4-4 REA E birbor ter ty iy eg Vis if musi standart e qoeesou Toeo O QW 1OHM/18 ————— ie Is ey fh AY tat fT ieey aha ae Heyy e M « q : é i) a 9 \ ) \ oe ea i wea 7 ab ial) I ae sea fa? § ? ALLAN HANCOCK FOUNDA TLO.N* PUBLICATIONS OF THE UNIVERSITY OF SOUTHERN CALIFORNIA First SERIES ALLAN HANCOCK PACIFIC EXPEDITIONS VOLUME 2 1935-1940 THE UNIVERSITY OF SOUTHERN CALIFORNIA PRESS LOS ANGELES, CALIFORNIA 1940 ALLAN HANCOCK FOUNDAT T@® PUBLICATIONS ALLAN HANCOCK PACIFIC EXPEDITIONS VOLUME 2 1935-1940 THE UNIVERSITY OF SOUTHERN CALIFORNIA PRESS LOS ANGELES, CALIFORNIA 1940 1136 14. 15: 16. CONTENTS A New Brittle Star from the Galapagos Islands, by Fred Ziesen- henness (Plateys))). >... pele Ree A ee dN eal ce Ne Eee ie ee Description of A New Blennioid Fish of the Genus Acanthemble- maria from the Pacific Coast of Panama, by George S. Myers and Barley Reda a 2A. UN ANE EA SL de a cee ee eee A New Genus of Distomes (Trematoda) with Lymphatic Vessels, bys Harold WW. Manter. (Plate 2)2 oe Parasitic Copepods Taken During the Third Hancock Expedition to the Galapagos Islands, by Charles Branch Wilson. (Plate 3).......... Some Monogenetic Trematodes from the Galapagos Islands and the Neighboring Pacific, by Frank G. Meserve. (Plates 4-10)................ Three New Trematodes from the Galapagos Marine Iguana Amblyrhynchus cristatus, by Paul T. Gilbert. (Plates 11-12) ........... Eight New Species of Gobioid Fishes from the American Pacific @oast; by Isaac. Ginsburg oe ce ah Land and Brackish Water Mollusca of Cocos Island, by G. Dallas Hanna. and Deo (George Merten 2) Nematode Parasites of the Galapagos Land Iguana, by Ashton C. GCucklersat (Bates. 013= 1/5) ease erred ‘A New Species of Nycteribiidae (Diptera Pupipara) from Islands in the Gulf of California, by Hugh Scott. (Plate 16)...............--.---------++ A Remarkable New Genus of Sea-Urchin (Spatangidae), by Hu- bertgbymani Clark. s(Blatey 1:70) senses oe eee es Marine Mollusks from Panama Collected by the Allan Hancock Expedition to the Galapagos Islands, 1931-1932, by A. M. Strong and, Leo George Hertlemn. (Plates, 18-23 ))--- -.< 22-2 -n2sacessccscceeesaceeeesesteteeeee Revision of the Nemertean Fauna of the Pacific Coasts of North, Central, and Northern South America, by W. R. Coe. (Plates Digenetic Trematodes of Fishes from the Galapagos Islands and the Neighboring Pacific, by Harold W. Manter. (Plates 32-50).......... The Acanthocephala Collected by the Allan Hancock Pacific Ex- pedition, 1934, by Harley J. Van Cleave. (Plates 51-55) _.........-.------------ The Geographical Distribution of Digenetic Trematodes of Ma- rine Fishes of the Tropical American Pacific, by Harold W. JNA ee ee ee enn 109-122 123-136 137-166 167-172 173-176 177-246 247-324 325-500 501-530 531-547 549-557 100% ] REPORTS ON THE COLLECTIONS OBTAINED BY THE HANCOCK PACIFIC EXPEDITIONS OF VELERO III OFF THE COAST OF MEXICO, CENTRAL AMERICA, SOUTH AMERICA, AND GALAPAGOS ISLANDS IN 1932, 1n 1933, in 1934, anv in 1935. A NEW BRITTLE STAR FROM THE GALAPAGOS ISLANDS By FRED ZIESENHENNE Tue University OF SOUTHERN CALIFORNIA PUBLICATIONS Tue Hancock Paciric ExPEDITIONS Votume 2, NuMBER 1 Issuep Marcu, 1935 Tue University oF SOUTHERN CALIFORNIA Press Los ANGELES, CALIFORNIA , C2 » w294%3 Nez ‘4 it, A NEW BRITTLE STAR FROM THE GALAPAGOS en ISLANDS (WitH One Pate) By FRED ZIESENHENNE The University of Southern California Invertebrate Laboratory During the winters of 1932-33 and 1933-34 it was a privilege to be a member of a party of scientists on a zoological survey of the Galapagos Islands under the leadership of Captain G. Allan Hancock, who sponsored the Hancock Pacific Expeditions of 1932, of 1933, of 1934, and of 1935. One of the most interesting specimens taken on the 1933 Expedition was a new species of the genus Ophioplocus taken in the waters of the Galapagos Islands. The author wishes to express his indebtedness to H. L. Clark, Museum of Comparative Zoology, for his personal and invaluable help in connection with the description of this new species and to express his appreciation to the staff of the Museum of Comparative Zoology for the opportunity of spending some weeks studying their collections. OPHIOPLOCUS HANCOCKI, new species Plate 1, figures 1, 2 Locality.—The original specimen was taken shore collecting on the north sandy beach of Cartago Bay, Albemarle Island of the Gala- pagos Islands at low tide, Feb. 13, 1933. It was collected from beneath surface rocks in a sandy-covered tide pool in a foot of water and partially imbedded in the sand. Its coloration blended in with the sand so that it could easily be overlooked. An additional specimen was taken on a rocky tide flat, again em- bedded in sand under surface rocks on Jan. 20, 1934, Station 168-34. Another was collected at low tide in Academy Bay, Indefatigable Isle of the Galapagos Islands. Bed Z THE HANCOCK PACIFIC EXPEDITIONS VOL. 2 Three specimens were taken shore collecting in a tide pool a quarter mile south of Ritter’s Landing at Black Beach, Charles Isle of the Galapagos Islands, Station 199-34. Description—Disk 13 mm. in diameter, arms 35-37 mm. long. Disk covered with a coat of rather coarse scales, smaller ones min- gled with the larger, the latter slightly swollen making the whole surface rough and irregular; primary plates small but distinct; radial shields very small, nearly or quite concealed by numerous small disk scales; interradial margins of disk sharply defined by 5-7 large plates, of which the median is largest. Arm segments wider than long; dorsal plates broken up into a large number (20-30) of small polygonal plates of diverse sizes, forming a remarkably smooth pavement continuous with the disk covering; the distal lateral plate on each side is larger than the rest. Interbrachial areas below cov- ered with fine scales; genital slits about equal to the three basal arm segments. Oral shields pentagonal with lateral and distal cor- ners rounded; madreporite nearly circular; adoral plates medium, swollen, longer than the distal width, separated distally by the first ventral armplate but meeting within; oral papillae five or six on each side, penultimate twice as large as others. First under arm plate small, triangular, or low pentagonal, succeeding plates squarish, as wide as long. Side arm plate more or less covered, especially orally, by a shagreen-like skin; each one bears three stout flattened, bluntly pointed spines, as long as segment; lowest spine slightly the longest. Tentacles scales three or four, two larger ones on proximal side of pore and two or one much smaller on distal side; distally the scales become less distinct and often only one is evident. Color in alcohol, disk cream yellow with irregular brown mark- ings, in some of which the radial shields are usually included; arms cream color with brown bands on every sixth segment; arm spines nearly white; interbrachial areas below cream color speckled with about a dozen dull purple spots; proximal ventral plates more or less dusky; distally the brown bands of the arm are indicated by dusky ventral plates. In the dried specimen the yellow tint is lost and the disk and upper surface of the arms are a light grey with the dark markings conspicuous. Types.—The type is deposited at the United States Museum. The co-types are deposited at: the Museum of Comparative Zoology, Cambridge, Mass., number 4834; the Zoological Museum, University no. l ZIESENHENNE: A NEW BRITTLE STAR 3 of Copenhagen, Denmark; The University of Southern California, Los Angeles, Calif., and the Velero III Collection, Los Angeles, Calif. Remarks.—This species is remarkably interesting because the genus has a curious discontinuous distribution. There is one species in Japanese waters, one in the East Indies and Tropical Australian regions, one on the Southern Australian Coast, one in New Zealand, one along the Central American coast and north to Southern Cali- fornia, and now this new and particularly well-marked species from the Galapagos and presumably endemic there. It is instantly recog- nizable by the numerous plates on the upper side of the arm seg- ments, their small size, and the closely fitted smooth pavement which they form. More material may show that the coloration is also distinctive. 4 THE HANCOCK PACIFIC EXPEDITIONS VOL. 2 EXPLANATION OF PLATE Fig. 1. Ophioplocus hancocki, new species, dorsal view x .7 Fig. 2. Ophioplocus hancocki, new species, ventral view x 2.3 (Photograph of para-type at The University of Southern California) STAR BRITTLE A NEW ZIESENHENNE: MNDLITSM\DI More LIAATLO MOU TY REPORTS ON THE COLLECTIONS OBTAINED BY THE HANCOCK PACIFIC EXPEDITIONS OF VELERO III OFF THE COAST OF MEXICO, CENTRAL AMERICA, SOUTH AMERICA, AND GALAPAGOS ISLANDS IN 1932, 1n 1933, in 1934, anv 1n 1935. DESCRIPTION OF A NEW BLENNIOID FISH OF THE GENUS 4ACANTHEMBLEMARIA FROM THE: PACIFIC COAST @F PANAMA By GEORGE S, MYERS and EARL D. REID Tue University oF SouTHERN CALIFORNIA PUBLICATIONS Tue Hancock Paciric ExpepITIons VotumMeE 2, NumBrErR 2 IssueD DecemBeER, 1936 Tue University oF SouUTHERN CALIFORNIA Press Los ANGELES, CALIFORNIA Copyricut 1936 BY Tue Universiry oF SOUTHERN CALIFORNIA DESCRIPTION OF A NEW BLENNIOID FISH OF THE GENUS ACANTHEMBLEMARIA FROM THE PACIFIC COAST OF PANAMA* By GEORGE S. MYERS, Stanford University, and EARL D. REID United States National Museum Among the fishes obtained by Dr. Waldo L. Schmitt, Curator of Marine Invertebrates in the United States National Museum, during the 1935 cruise of Capt. G. Allan Hancock’s yacht Velero III, we find a most interesting new species of the genus Acanthemblemaria. The three hitherto-known species of the genus are all West Indian (Metzelaar, 1919, p. 159; Beebe and Tee-Van, 1928, pp. 244-249). Acanthemblemaria hancocki, new species Holotype-—U.S.N.M. 102015, a specimen 31.8 mm. in standard length, taken February 4, 1935, on the outer side of the smaller, westernmost island of the Secas Islands, Pacific coast of Western Panama. Hancock Pacific Expedition, 1935. Paratypes.—U.S.N.M. 102016, two specimens 30.8 and 31 mm. in standard length; same data as holotype. Dorsal XXII to XXIII, 13 to 14. Anal II, 24 to 25. Pectoral 13. Pelvic 3. Caudal 16. Body moderately elongate, trunk compressed, greatest depth at origin of pectoral. Occipital region of skull rather bulging on each side, but upper profile of head continuously decurved from dorsal fin to snout tip. Head 3.7 to 3.9 in standard length, depth 5.8 to 6.1, predorsal distance 5 to 5.2, preanal distance 2.3 to 2.5. Pectoral 1.2 in head length (measured to upper angle of gill opening), pelvics 2.3, caudal 1.5, snout 7.7 to 7.9, interorbital 6.4 to 6.7, maxillary 1.8 to 2.3, extending slightly past posterior rim of orbit. * Published with the permission of the Secretary of the Smithsonian Institution. biwed 8 THE HANCOCK PACIFIC EXPEDITIONS VOL. 2 Teeth in upper jaw in a strong outer row which extends back- ward to opposite middle of palatine patch, and a series of extremely minute inner teeth. Vomer with four strong teeth arranged in a square. Palatine patches with two rows of teeth, the patches being elongate-oval in shape. Teeth of lower jaw in a single strong outer row with a few very small teeth set in two irregular rows behind the main one at front of jaw. Both upper and lower jaws are rather expanded and flattened in front (the symphyses indented) and then rather suddenly constricted as the rami turn and run backwards. This formation of the jaws is apparently that described by Beebe and Tee-Van (in other species) as that of an old-fashioned key-hole. It might better be described as like the jaws of Hippopotamus. The main jaw teeth are strong though rather short, pointed, and slightly compressed in front. The front teeth in each jaw flare outward slightly. Entire front of upper part of head, forward of the vertical of the posterior rim of orbit, covered with fine blunt spines. The spinous area includes the whole frontal and preocular region, the suborbitals, and a patch on top of the head behind the eyes extending backward in a blunt point toward (but not reaching) the vertex of the supra- occipital region. The interorbital is strongly concave, forming a trough in the middle, and is armed with three rows of spines on each side, the outer row being part of the single circumorbital spiny ring. This ring is complete except directly behind the eye. Orbital tentacle short, apparently simple. Nasal tentacle longer and multifid, but not as long as that of 4. arborescens. Opercle and preopercle naked. A group of five or six pores on either side of nape about opposite origin of dorsal fin. Opercle ends above in a free, hook-like membrane supported by the branchiostegal rays, which reach notably above the point of attachment of the gill-cover. Vertical fins of moderate height, soft rays longer than spines, the last rays attached at caudal base by a membrane. Origin of dorsal above preopercle, directly at base of cranium, which has no supra- occipital crest. Pelvics inserted in front of pectoral base. Body light straw-colored, the head blackish with darker spots and lighter marblings, the principal dark area being a large hourglass- shaped saddle set transversely across the occiput and extending down on opercles to opposite lower rim of eye. About four brown dots on margin of opercle. Body with two main longitudinal rows No. 2 MYERS AND REID: A NEW BLENNIOID 9 of dark brown spots, as large as eye in front but diminishing rapidly posteriorly, the upper row along the base of the dorsal and encroach- ing a little on the basal fin membranes, the lower row at mid-line of body. Another less conspicuous row of spots along anal base, these chiefly on the membranes. A single row of very fine dots just below the dorsal series and set alternately with each dorsal blotch. A similar row between the main central series of blotches and the anal series; this row may be very indistinct or nearly absent. Dorsal and anal faintly and narrowly bordered with dark. Pectorals and caudal clear. Pelvics brownish. Often the first few dorsal spines and their membranes dark brownish, fading posteriorly. The entire color effect is that of a black-headed, straw-colored fish with longitudinal series of spots which decrease in size posteriorly. We are not certain to which of the three described species of Acanthemblemaria our new species is most closely related. Beebe and Tee-Van separate spinosa of Metzelaar from the others by the supposed lack of small teeth behind the main jaw series. It seems probable to us that Metzelaar’s fish also had these small teeth, as they are very difficult to detect without the use of tooth-impressions made with modeling clay. Beebe and Tee-Van further separate arborescens from variegata on the profile of the head and the area of its spinosity, on the structure of the orbital tentacle, and on the color. The head profile of our form differs from that of the other three, and the area of spinosity on the top of the head is hard to compare without actual specimens of the other species in hand. Our species differs from arborescens and spinosa and agrees with variegata in the simple ocular tentacle, but agrees with arborescens and differs from the other two in the shape of the jaws and mouth as illustrated in the figures. It differs widely from all three in the unusual coloration. 10 THE HANCOCK PACIFIC EXPEDITIONS VOL. 2 LITERATURE CITED Beese, Witiiam, and Joun Trer-Van 1928. The fishes of Port-au-Prince Bay, Haiti, with a summary of the known species of marine fish of the island of Haiti and Santo Domingo. Zoologica. Sci. Contrib. N.Y. Zool. Soc., vol. 10, no. 1, pp. 1-279. MetzeLaar, JAN 1919. Report on the fishes collected by Dr. J. Boeke in the Dutch West Indies, 1904-1905, with comparative notes on marine fishes of tropical West Africa. In: Boeke, J., Rapp. voorl. onderz. toest. Visscherij Industr. Zeeprod. Kol. Curacao, tweede ged., 1919, bijl. 1, pp. 1-315. The Hague. REPORTS ON THE COLLECTIONS OBTAINED BY THE HANCOCK PACIFIC EXPEDITIONS OF VELERO III OFF THE COAST OF MEXICO, CENTRAL AMERICA, SOUTH AMERICA, AND GALAPAGOS ISLANDS IN 1932, 1n 1933, 1n 1934, in 1935, In 1936, anv in 1937. A NEW GENUS OF DISTOMES (TREMATODA) Wl LYMPHATIC VESSEES By H. W. MANTER Tue UNiversiry oF SouTHERN CALIFORNIA PUBLICATIONS Tue Hancock Paciric ExpepitTions IssueD June, 1937 Tue Universiry oF SOUTHERN CALIFORNIA Press Los ANGELES, CALIFORNIA A NEW GENUS OF DISTOMES (TREMATODA) WITH LYMPHATIC VESSELS* 7G & es 4 Sly , #4 ne (Wir One Pate) ih | ste fiuti ti Aw a es \ H. W. MantTer re eo University of Nebraska St, Was! oy Rs The trematodes described in this paper are but two of over 100 species collected from marine fishes in 1934, during the third G. Allan Hancock Expedition to the Galapagos Islands. The author’s presence on this expedition was sponsored in part by the Carnegie Institution of Washington. A brief preliminary report on the trema- todes collected has been made (Manter, 1934) and a more complete report on the digenetic forms is in preparation. An early description of these two forms is felt justified in view of their significance in connection with the phylogeny of the Distomata. The author has already indicated (Manter, 1935) a relationship between certain allocreadiid-like distomes (Megasolena Linton and Hapladena Lin- ton) and amphistomes, The new genus described below further sub- stantiates such a view and indicates that the Anallocreadiinae in particular may be involved. A discussion of these relationships will follow a description of the new species. Apocreadium mexicanum, new genus, new species (Plate 2, figs. 1-3) Host: Labrisomus xanti Gill Position: Intestine Locality: Tangola Tangola, Mexico Incidence: 18 specimens from a single host The body is elongate, tapering slightly and bluntly rounded at the anterior end, pointed at the posterior end, much flattened, espe- cially posterior to midbody where the edges of the body become very thin and thrown into frill-like folds. The cuticula is scaled as far back as midbody. Mature specimens measure from 2.151 to 4.110 mm. in length by 0.757 to 1.096 mm. in greatest width. The body * Studies from the Zoological Laboratories, the University of Nebraska, No. 191. pl 12 THE HANCOCK PACIFIC EXPEDITIONS VOL. 2 is approximately equally wide, except at the anterior and posterior fourth. The acetabulum is well anterior to midbody, the forebody being usually 1/4 to 1/5 total body length. Both suckers are sub- circular with a tendency to be slightly longer than wide. The oral sucker is 0.225 to 0.315 mm. in diameter. The acetabulum is 0.352 to 0.502 mm. in diameter. Its aperture is transverse. The sucker ratio is approximately 2:3 or 3:5. Young specimens show a few pigment granules dorsally in the forebody but these are lacking in older specimens. There is a short but distinct prepharynx. The pharynx is longer than wide, 0.142 to 0.202 by 0.112 to 0.165 mm. Its anterior fourth is modified as a sphincter region composed of circular muscles (sug- gesting the character of the pharynx in Gyliauchen) while the pos- terior region is composed of radial muscles. There is a distinct esophagus somewhat shorter than the pharynx. The intestinal bifur- cation is approximately midway between the suckers. The ceca are narrow and extend to a point a short distance from the posterior end where the body begins its rather abrupt tapering to the posterior tip. Each cecum ends blindly. The excretory vesicle is a long narrow tube extending anteriorly from the pore at the posterior tip of the body to the posterior testis where it spreads slightly to right and left and narrows to become a collecting tube on each side. Each collecting tube shortly after it leaves the vesicle forks into two tubules both extending forward, both at first median to the cecum, the larger tubule median to the smaller. Anterior to the acetabulum they are both lateral to the cecum. They seem to end near the level of the pharynx. Posterior to the level of the testes a very small excretory tubule can be seen on each side. These two posteriorly directed tubules arise at the same point where the anterior tubules unite. They extend to the posterior end of the body. The lymphatic system consists of four longitudinal vessels close to the intestinal ceca, sometimes median, sometimes dorsal and ventral. Two of these lymphatic vessels extend anterior to the oral sucker to the extreme anterior end of the body where they end blindly. The longitudinal vessels do not give off side branches ex- cept in the posterior half of the body. Shortly behind the testes vesicle-like portions of the lymphatic system appear in the extreme lateral regions of the body. These are especially numerous near the NO. 3 MANTER: A NEW GENUS OF DISTOMES 13 posterior end of the body where they are obvious in toto-mounts. Posterior to the testes each of the four vessels splits to form two making a total of four pairs. Each vessel is much branched, the ends of the branches extending to near the edge of the body. These tips are often swollen (plate 2, fig. 2). The genital pore is median close to the anterior edge of the acetabulum. The testes are more or less rectangular in outline, slightly lobed, tandem, close together, approximately in the middle of the body. Except in young individuals (where the testes are of about equal size) there is a distinct tendency for the anterior testis to be wider than long, smaller and less lobed while the posterior testis tends to be longer than wide, larger and more deeply lobed. The posttesticular space is very long, sometimes more than % body length. A large, elongated sac-like seminal vesicle occurs immediate- ly posterior to the acetabulum and overlapping the ovary. Anter- iorly it narrows into a fine tube which continues without modifica- tion to near the anterior edge of the acetabulum where it joins the uterus to form a simple tubular genital sinus. Prostate gland cells are lacking unless represented by a few scattered cells around the male duct. A cirrus and cirrus sac are lacking. The narrow straight tube from seminal vesicle to genital pore is not muscular and since the pars prostatica cannot be distinguished from a cirrus portion, the tube might be termed the ejaculatory duct. It seems to have the same structure after its union with the uterus to form the ductus hermaphroditicus or genital sinus. The ovary is spherical, midway between the anterior testis and the acetabulum, slightly to the right, just median to the right cecum. Mehlis’ gland is well-developed, lying between ovary and anterior testis. A large flask-shaped seminal receptacle extends anterior to the ovary almost to the acetabulum. Laurer’s canal is well-develop- ed, coiled, and opens dorsally at mid-ovary level. The uterus is pre- testicular filling most of the area between testes and acetabulum, wholly to the left of the ovary and largely to the left of midbody axis. It becomes a straight tube dorsal to the acetabulum and joins the male duct near the anterior edge of the acetabulum. The eggs are fairly thin-shelled, 61 to 67 by 31 to 34 p. The vitelline follicles extend from the level of the ovary to near the posterior end of the body. In 13 specimens studied the follicles reached the posterior border of the acetabulum in 2 (in which the ovary also was far for- 14 THE HANCOCK PACIFIC EXPEDITIONS VOL. 2 ward) and in none did they reach the extreme posterior tip of the body. The vitellaria largely fill the body posterior to the testes and form two longitudinal intercecal, posttesticular areas. GENERIC DIAGNOSIS OF APOCREADIUM Elongate distomes with body much flattened posterior to mid- body where the edges are very thin. Acetabulum anterior to mid- body, larger than oral sucker. Pharynx well developed with an an- terior region of circular muscles. Ceca extending not very far apart to near posterior end. Testes in midbody region, tandem, intercecal, close together. Seminal vesicle large, undivided, sac-like. Cirrus and cirrus sac lacking. Prostate cells poorly developed. A tubular genital sinus present. Genital pore median at anterior edge of acetabulum. Ovary spherical, pretesticular, slightly to the right. Mehlis’ gland large, postovarian; Laurer’s canal and seminal receptacle present. Uterus pretesticular, largely to the left. Vitellaria follicular in sides of body, confluent posterior to testes. Excretory vesicle I-shaped with 2 pairs of anterior and 1 pair of posterior tubules. Lymphatic sys- tem of 4 large longitudinal vessels branching at least in posterior half of body. Type species: Apocreadium mexicanum. SPECIFIC DIAGNOSIS OF Apocreadium mexicanum (Measurements in mms.) Body rounded anteriorly, pointed posteriorly; scaled to mid- body; 2.151 to 4.110 by 0.757 to 1.096. Acetabulum 1/4 to 1/5 from anterior end, 0.352 to 0.502 in diameter, with transverse aperture; oral sucker 0.225 to 0.315 in diameter. Prepharynx and esophagus present; intestinal bifurcation midway between suckers. Four longi- tudinal vessels branched in posterior half of body. Genital pore me- dian at anterior edge of acetabulum. Seminal vesicle just posterior to acetabulum, overlapping ovary; genital sinus tubular, shorter than ejaculatory duct. Ovary spherical; seminal receptacle extend- ing anterior to ovary; uterus to left of ovary; eggs 61 to 67 by 31 to 34 y; vitellaria from near posterior edge of acetabulum to near posterior edge of body. Host: Labrisomus xanti Gill The name Apocreadium is from apo: away from and creadium and implies the fundamental differences between this trematode and the Allocreadiidae. The name mexicanum is for the locality. No. 3 MANTER: A NEW GENUS OF DISTOMES 15 Apocreadium longisinosum, new species (Plate 2, figs. 4-7) Hosts: Cheilichthys annulatus (Jenyns) Albermarle Island and Charles Island, Gala- pagos Islands Spheroides angusticeps (Jenyns) Charles Island, Galapagos Position: rectum Incidence: 2 to 10 in a host, total of 15 collected from 3 hosts. The body is orange-yellow in its posterior half, unspined, more or less flattened, 6.57 to 9.65 by 1.552 to 2.403 mm., widest about at midbody, tapering toward each end. A 4.650 mm. specimen was immature. The posterior third of the body is thin and flexible with numerous lateral folds. It tapers sharply to a pointed posterior end. The anterior half of the body is more plump, smooth, and tapers gradually. A small, fleshy preoral lobe is present. The oral sucker is subcircular but usually slightly longer than wide, 0.375 to 0.532 mm. in transverse diameter. The acetabulum is about 14 body length from the anterior end, is longer than wide, 0.675 to 0.885 mm. in transverse diameter. Its aperture is longitudinal. ‘The sucker ratio is approximately 5:8. The forebody measures 1.360 to 2.430 mm. There is a fairly short prepharynx (about % pharynx length). The pharynx is usually somewhat pyriform in shape. The anterior third is more narrow, provided with a larger number of circular muscles, and separated from the posterior region by a very slight constriction. Muscles extend from the oral sucker to the pharynx outside the prepharynx. The esophagus is approximately the same length as the prepharynx. The intestinal bifurcation is usually a little nearer the oral sucker than the acetabulum but it may be ap- proximately midway between the suckers. The narrow ceca extend some distance in from the body margins to within a short distance of the posterior end. They do not reach the posterior end and may fail to do so by some distance. One curious abnormality involved the left cecum which was almost completely degenerate except for a short normal-appearing stub barely reaching beyond the bifurca- tion and ending abruptly. The remainder of the cecum was repre- sented by a few strands of fine fibrous tissue. 16 THE HANCOCK PACIFIC EXPEDITIONS VOL. 2 The genital pore is median very closely anterior to the acetab- ulum. It may even be directly ventral to the anterior edge of the acetabulum. The testes are immediately posterior to midbody, tan- dem, close together, lobed, squarish in shape. The posterior testis is usually slightly longer. The posttesticular space varies from 2.497 to 4.455 mm. being always considerably longer than the forebody. The seminal vesicle is a large, elongate, thin-walled sac, free in the parenchyma, extending backward from near the posterior edge of the acetabulum almost to the ovary from which it is separated by the seminal receptacle. The pars prostatica is about the same length as the seminal vesicle. It extends uncoiled diagonally forward dorsal to the acetabulum or, rarely, along the right side of the acetabulum. Its lumen is narrow and smooth, its wall fairly thick and cellular, surrounded by a few prostatic gland cells. These flattened and gran- ular gland cells lie free in the parenchyma and are most numerous near the vesicle. The uterus enters the pars prostatica dorsal to the acetabulum to form a long tubular slightly muscular ductus herm- aphroditicus or genital sinus. This tube bends ventrally toward the genital pore at the anterior edge of the acetabulum or may seem to bend back to reach the genital pore from an anterior direction (plate 2, fig. 5) but this appearance may be due to flattening of the speci- men. The genital sinus is approximately the same length as the pars prostatica. Its lumen is wide, its wall fairly thin but muscular and surrounded by a few rounded non-granular cells. The ovary is globular, pretesticular, to the right near the right cecum, It is separated from the anterior testis by a short space occupied by Mehlis’ gland and the yolk reservoir. The uterus arises from the posterior side of the ovary and extends back as far as the anterior testis whence it coils forward to occupy the intercecal space to the left and anterior to the ovary. It joins the pars prostatica dorsal to the acetabulum as noted. A large seminal receptacle is present anterior to the ovary adjacent to the seminal vesicle. It connects to the oviduct posterior to the ovary. Laurer’s canal is well developed, coiled, opening on the dorsal surface just anterior to the ovary. Eggs measure 88 to 102 by 48 to 60 p, usually about 95 by 54 yw. The vitelline follicles extend from the level of the ovary to the posterior end of the body. At first extracecal, they become con- fluent posterior to the testes. No. 3 MANTER: A NEW GENUS OF DISTOMES i The excretory system is like that of Apocreadium mexicanum. The narrow excretory vesicle gives rise near the posterior testis to 2 pairs of anteriorly directed tubules, one pair larger than the other. Both pairs extend forward at least as far as the acetabulum but only one pair seems to reach as far as the oral sucker. From the common stem of each pair near the median vesicle a single sinuous tubule passes posteriorly on each side. The lymph vessels are well developed. They are considerably branched in the posterior half of the body as in 4. mexicanum. The branches run almost parallel with the stems, diverging gradually toward the body surface. They are not swollen at their tips as are such branches in 4. mexicanum. The lymph vessels of the forebody also branch but here the branches are shorter and may extend in any direction. Because of the courses taken by the branches, the number of main stems of the lymph system is very difficult to deter- mine. For some distance posterior to the testes there seem to be 4 pairs of longitudinal tubes, although 2 pairs extend farther back than the others. In the region of the acetabulum there seem to be 2 pairs. An accurate count was not possible in the forebody. In most specimens one pair extended into the preoral lobe. Evidently the lymph system is very similar to that of 4. mexicanum. Lymphocytes or at least large cells of some kind (plate 2, fig. 7) are not infrequent within the lymph vessels. These cells seem to have been amoeboid. They measure 14 to 19 » in diameter which is as great as the diameter of most of the lymph vessels. The cyto- plasm of these cells is finely granular, the nucleus staining very deeply, much more deeply than those of other cells. SPECIFIC DIAGNOSIS OF Apocreadium longisinosum (Measurements in mms.) Body tapering toward each end, pointed at posterior end, widest at midbody, 6.57 to 9.65 by 1.552 to 2.403, in life orange-yellow in color. Oral sucker 0.375 to 0.532 in diameter; acetabulum % from anterior end, 0.675 to 0.885 in diameter, with longitudinal aperture. Genital pore median close in front of acetabulum. Short prepharynx, pharynx 0.210 to 0.292 (length) by 0.225 to 0.315 (width), anterior third slightly modified; esophagus short; bifurcation about midway between suckers; ceca narrow extending to near posterior end. Testes tandem, close together, slightly lobed, squarish, just poster- 18 THE HANCOCK PACIFIC EXPEDITIONS VOL. 2 icr to midbody. Seminal vesicle elongated sac-like from acetabulum to near ovary; pars prostatica about as long as vesicle, straight; ductus hermaphroditicus a simple muscular tube as long as pars prostatica. Ovary globular; Mehlis’ gland posterior to ovary; semi- nal receptacle anterior to ovary; uterus between testes and acetab- ulum; eggs 88 to 102 by 48 to 60y; vitellaria from ovary to pos- terior end, confluent behind testes. Excretory vesicle extending to testes; 2 pairs of anterior and 1 pair posterior collecting tubules. Lymph vessels well developed, much branched, apparently funda- mentally 2 pairs of longitudinal stems forking to form 4 pairs along much of body length. Type host: Cheilichthys annulatus. Other host: Spheroides angusticeps, a related fish. Type locality: Galapagos Islands. The name longisinosum refers to the long genital sinus. Comparisons. A. longisinosum is more than twice larger than J. mexicanum and the body is relatively wider. The aperture of the acetabulum is longitudinal rather than transverse. The vitellaria do not nearly reach the acetabulum as they do in 4. mexicanum, a dif- ference correlated with the larger uterus in 4. longisinosum. In A. longisinosum the genital sinus is much longer; the eggs much larger (maximum length 102 » compared with 67 ,); the lymph vessels more branched anteriorly. In spite of these differences the species are very similar and clearly congeneric. There are genera of the Allocreadiidae with the cirrus sac weak- ly developed or lacking, for example the Anallocreadiinae and Opecoeliinae, but Apocreadium differs from most in its tubular geni- tal sinus and from all in its lymphatic system. It is probably signifi- cant that the Anallocreadiinae which lack a cirrus sac also possess a tubular genital sinus described as “a common tube” in the form of an “unspecialized cloacal invagination” by Simer (1929, p. 564) for Anallocreadium armatum; as a “long genital sinus” by Manter (1926, p. 87) for Homalometron pallidum; as “an invaginated clo- aca” by Hunter & Bangham (1932, p. 138) for Anallocreadium pear- sel; but as a “genital atrium” by Manter (1936, p. 34) for Crassi- cutis cichlasomae. In this latter case however, the “atrium” may be tubular in form. The genus Apocreadium then shows evidence of relationship to the Anallocreadiinae. On the other hand, however, its lymphatic vessels, the structure of the pharynx and the excretory system sug- No. 3 MANTER: A NEW GENUS OF DISTOMES 19 gest the genera Megasolena and Hapladena for which Manter (1935, p. 438) named the subfamily Megasoleninae. The essential difference is the presence of an hermaphroditic sac in the Megasoleninae. Apo- creadium seems to stand almost midway between these two subfami- lies. If included in the Megasoleninae, the subfamily (and family) description must be altered to include forms with neither hermaphro- ditic nor cirrus sac; if included in the Anallocreadiinae the subfamily must be extended to include forms with a lymphatic system. For the present, the writer prefers to recognize the lymphatic vessels as of fundamental significance, especially since their presence is again as- sociated with pharyngeal modifications and to classify Apocreadium in the Megasoleninae. Discussion. For many years it has been the custom to classify digenetic trematodes into three groups, the Amphistomata, Mono- stomata, and Distomata. But it has been increasingly apparent that these divisions are heterogeneous and not natural. Some monostomes (e. g. the Angiodictyidae) are actually amphistomes which have lost their posterior sucker. Other monostomes are evidently distomes which have lost the ventral sucker. In other words, members of these groups may show closer relationship to one of the other groups than to members of its own group. Amphistomes are generally considered as the most primitive. Little study has been made of possible rela- tionship between amphistomes and distomes. Dawes (1936, p. 177) remarks: “Nous savons vraiment peu de chose sur les relations qui existent entre les Distomata et les Paramphistomida; c’est un point qui est visiblement négligé par les zoologistes.” The author, however (Manter, 1935), has found strong evidence of such relationship exactly where it would be most expected, namely among trema- todes of fish. It even seemed necessary to classify two distome genera (Megasolena and Hapladena) among the Paramphistomida. These two genera showed certain features suggesting the family Allocreadi- idae where Megasolena at least was once classified. Apocreadium is still more evidently allocreadiid-like. It serves to link the Paramphistomida not only to the Allocreadiidae but to the Anallocreadiinae. But Apocreadium can be included in the Mega- soleninae especially if the lymphatic system is to be emphasized. There is, in fact, a fairly well graded series of forms between the amphistomes such as Gyliauchen and Opistholebes through Para- gyliauchen, Apocreadium and the Anallocreadiinae to the Lepo- 20 THE HANCOCK PACIFIC EXPEDITIONS VOL. 2 creadiinae. Even the position of the acetabulum is intermediate in some forms such as Paragyliauchen chaetodontis Yamaguti. Mega- solena and Hapladena are definitely associated with such a series but differ from the others in their peculiar hermaphroditic sac. There results a plausible conclusion that the large distome family Allocreadiidae probably evolved from amphistome ancestors. Or the amphistomes may have evolved from allocreadiid ancestry. Type specimens of the new species described in this paper are deposited in the United States National Museum. Paratypes are de- posited at The University of Southern California and in the author’s collection. No. 3 MANTER: A NEW GENUS OF DISTOMES 21 LITERATURE CITED Dawes, Ben 1936. Sur une tendance probable dans l’évolution des trématodes digénétiques. Ann. Parasit., 14:177-182. Hunter, Georce W. & Ratpw V. BANGHAM 1932. Studies on fish parasites of Lake Erie I. New trematodes (Allocreadi- idae). Trans. Amer. Micros. Soc., 51:137-152. Manter, H. W. 1926. Some North American fish trematodes. III]. Biol. Mon., 10:1-138. 1934. Preliminary observations on trematodes from the Galapagos Islands and neighboring Pacific. Ann. Rept., Tortugas Lab., Carnegie Inst. Wash., Year Book No. 33:260-261. 1935. The structure and taxonomic position of Megasolena Linton 1910 (Trematoda) with notes on related trematodes, Parasit., 27:431-439. 1936. Some trematodes of cenote fish from Yucatan. Carnegie Inst. Wash., Pub. No. 457, 33-38. Simmer, Parke H. 1929. Fish trematodes from the Lower Tallahatchie River. Amer. Mid. Nat., 11:563-588. 22 THE HANCOCK PACIFIC EXPEDITIONS VOL. 2 EXPLANATION OF PLATE 2 All figures were drawn with the aid of a camera lucida. The projected scale has the value (in mms.) indicated for each figure. Abbreviations: ac, acetabulum; ce, intestinal cecum; ex, excretory vesicle; gp, genital pore; gs, genital sinus; J, lym- phatic vessel; pp, pars prostatica; sr, seminal receptacle; sv, seminal vesicle; ut, uterus. Fic. Fic. Fic. Fic. Fic. Fic. 6 Fic. ier Apocreadium mexicanum. Dorsal view. A. mexicanum. Frontal section through posterior half of the body, showing the branching lymphatic vessels. A. mexicanum. Cross-section through the region of the seminal re- ceptacle. A. longisinosum. Ventral view. A. longisinosum. Terminal reproductive organs. A. longisinosum. Cross-section through anterior portion of the pharynx. A. longisinosum. Portion of two lymphatic vessels showing lympho- cytes. PLZ A NEW GENUS OF DISTOMES MANTER No. 3 2 y 09 ~ S2,29,° : ee if TF FOBU Hg anal Oh ven wis: A ae aa “it Pn) : oo Mejon ue weiss ‘i mt? e | { = ; 4 aah 2h ay 4 ee ways a ta a Ht ’ We ti | F hee, i | } | ' “i i] i] HM Z { $¢ r “a i] | ! ' P 6 “ ' REPORTS ON THE COLLECTIONS OBTAINED BY THE HANCOCK PACIFIC EXPEDITIONS OF VELERO III OFF THE COAST OF MEXICO, CENTRAL AMERICA, SOUTH AMERICA, AND GALAPAGOS ISLANDS IN 1932, In 1933, in 1934, my 1935, in 1936, anv in 1937. PARASITIC COPEPODS TAKEN DURING THE THIRD HANCOCK EXPEDITION TO THE GALAPAGOS ISLANDS By CHARLES BRANCH WILSON Tue University oF SouTHERN Ca tirorniA PusBLicATions Tue Hancock Paciric ExpepiTions Votume 2, Numper 4 Issuep June, 1937 Tue University oF SOUTHERN CALIFORNIA Press Los ANGELES, CALIFORNIA PARASITIC COPEPODS TAKEN DURING THE THIRD HANCOCK EXPEDITION TO THE GALAPAGOS ISLANDS (With One Pirate) Cuartes Brancu WItson The New England Museum of Natural History, Boston, Massachusetts - The valuable collections made during the third Hancock Expedi- tion to the Galapagos Islands included the copepods parasitic upon fish. These were gathered not only from the local fish around the islands but also from those captured during the passage to the islands and back. There are thus included among the hosts, fish from the Pacific coasts of Mexico, Central America, Colombia, and Ecuador as well as those from the immediate vicinity of the Gala- pagos Islands. The parasites were collected and preserved by Dr. H. W. Man- ter of the University of Nebraska, who accompanied the expedi- tion, and were sent to the author for identification. The host identi- fication is incomplete in one or two instances since the personnel of the expedition did not include an ichthyologist. Upon examination the collection of parasitic copepods thus ob- tained has proved to possess peculiar value and interest. This is due chiefly to the exceptional confirmation they afford of species al- ready established but far removed in time, host, or habitat. Practi- cally every one of the species here enumerated contributes new and important information to supplement previous records. This appears in the re-establishment of one species which had been virtually for- gotten, since it had never been reported after its first discovery 75 years ago. Two other species almost as old have hitherto included but a single sex, in the one case the male, in the other the female. In both instances the missing sex is here supplied and is described and fig- ured for the first time. Furthermore, these records furnish an abun- dance of new hosts and localities, some of which are very far re- moved from those previously reported. With the exception of the two new sexes, whose types have been deposited in the National Museum, all the specimens have been returned to The University of Southern California. For the privilege [ 23 ] 24 THE HANCOCK PACIFIC EXPEDITIONS VoL. 2 of reporting upon this collection thanks are hereby returned to the sponsor and the officials of the expedition and to Dr. Manter who collected the specimens. CALIGOIDA CALIGIDAE CaLicus BALISTAE Steenstrup & Liitken Caligus balistae Steenstrup and Liitken, Kong. Danske Vid. Selsk. Skrift., ser. 5, vol. 5, p. 356, pl. 1, fig. 1, 1861. A single male was washed from the gill chamber of an unidenti- fied fish at Albermarle Island. The genital segment and abdomen of this specimen differed somewhat from the figures hitherto published as can be seen in plate 3, fig. 1. The abdomen is relatively shorter, the caudal rami are semicircular, and the lobes at the posterior corners of the genital segment nearly reach the distal end of the caudal rami. Cauicus Bonito Wilson Caligus bonito, Wilson, Proc. U. S. Nat. Mus., vol. 28, p. 589, pl. 13, 1905. A single female was taken from the gill cavity of a grouper pe- culiar to the Galapagos Islands, Cratinus agassizu Steindachner, at Tagus Cove, Albermarle Island. A single male was found on the red snapper, Lutianus novemfasciatus (Gill), at Tangola, Mexico. This species was originally discovered in the Woods Hole area and has been reported by Brian from the coast of Mauretania and by Yamaguti from Japan. These specimens add two new hosts as well as two new localities and indicate that the species is cosmopolitan. CALIGUS CHORINEMI Kollar Caligus chorinemi Kollar, mss. Kreeyer, Natur. Tidssk. 3 raekke, 2 bind, p. 67, pl. 5, fig. 1, a-h, 1863. A single female from an unidentified fish at Albermarle Island; 3 females and 3 males from the gills of Seriola dorsalis (Gill), at Port Culebra, Costa Rica; 3 females and 3 males from the same host at Port Utria, Colombia. The species was first described by Kreeyer from female museum specimens taken off the coast of Bra- zil. Both sexes were afterwards obtained from the same locality by Heller and the male was described and figured. But during the long interval since then the species has never been reported by any in- vestigator and its validity had become doubtful. These specimens No. 4 WILSON: PARASITIC COPEPODS 25 restore in full the original recognition, add a new host and two new localities, and afford some information with regard to development, since the females of the Colombian species were only half grown. Accordingly a figure and description of one of these young females are here included (plate 3, fig. 2). Young Female. Carapace a little longer than wide and about two thirds of the entire length; frontal plates wide and prominent, the lunules projecting as much as in the adult. The posterior median lobe is not much wider than the lateral lobes but projects consider- ably behind them. The lateral lobes curve inward as in the adult and are more angular at their outer corners. The free segment is two thirds as wide and almost half as long as the genital segment and is not contracted posteriorly. The genital segment is obovate, considerably narrowed anteriorly and a little wider than long, and is less than half its adult size. Its posterior margin is rounded instead of scalloped and it carries rudiments of a fifth pair of legs at its posterior corners. The abdomen closely resembles that of the adult in shape and proportion and already shows signs of segmentation in the form of lateral indentations. The appendages are the same as those of the adult except that the fourth legs appear larger and reach behind the posterior margin of the genital segment. Caxicus constrictus Heller (plate 3, figs. 3, a-i.) Caligus constrictus Heller, Reise der Novara, p. 175, pl. 15, fig. 5, 1865. Heller established this species upon a single male specimen taken from the gills of a Stromateus species in the Indian Ocean, and no other specimens have ever been reported. The present collection includes 2 females from the gills of Caranx hippos (Linnaeus), at Secas Island, Panama, a single female from the gills of the same host at San Francisco, Ecuador, and 4 females from the gills of a runner, Elagatis bipinnulatus (Quoy & Gaimard), at Bahia Honda, Panama. These 7 specimens are referred to Heller’s species because they certainly are not identical with any described Caligus females. And they agree so closely in structural details with Heller’s male as to preclude any idea of creating a new species for them. They thus confirm the establishment of Heller’s species and complete the species diagnosis by supplying the female. Female. Carapace orbicular, slightly wider than long; frontal plates with a nearly straight anterior margin, scarcely indented at 26 THE HANCOCK PACIFIC EXPEDITIONS VOL. 2 the center; lunules small, semilunar, and projecting but little. Median posterior lobe one third of the carapace width, not reaching behind the lateral lobes, with rather angular corners; lateral lobes curved strongly inward. Free segment one fourth the width of the cara- pace and considerably widened through the bases of the fourth legs; genital segment longer than the carapace, and half as wide as long, with nearly parallel sides and rounded lobes at the posterior corners. The anterior end of the segment is contracted into a long neck, narrower than the free segment and more or less wrinkled. On the ventral surface of the segment near the posterior end the two sexual openings, which lead to the semen receptacles, project backward a little side by side, and to their outer ends are attached the spermatophores. The latter are nearly spherical and reach back to about the center of the abdomen, thus forming a structure which at first sight suggests the rudimentary segment in Pandarus, to which however, it bears no analogy. The abdomen is one-jointed, one fourth the length and one third the width of the genital segment; the caudal rami are minute and armed with tiny setae. The terminal joint of the first antennae is linear and elongate; the second antennae are of medium size with a stout claw curved into a half circle. The maxilliped has a considerably inflated basal joint and a strong terminal claw. The first leg carries a rudimentary endopod which is finger-like and shows traces of segmentation and is tipped with a very short spine. The spine on the basal segment of the third exopod is exceptionally large and very strongly curved; the fourth leg is four-jointed with 5 spines, the three terminal joints combined a little shorter than the basal joint. These legs are weak and slender and scarcely reach the thickened portion of the genital segment, Total length, 5 mm. Carapace 2 mm. long, 2.2 mm. wide. Ovisacs 5 mm. long. One of the females from Caranx hippos, with ovisacs, has been selected and given Cat. No. 69866 U.S.N.M. Caticus 1sonyx Steenstrup & Liitken Caligus isonyx Steenstrup & Liitken, Kong. Danske Vidensk. Selsk. Skrifter, 5 raekke, p. 18, pl. 3, fig. 5, 1861. This species was based upon a single female taken from a great barracuda, Sphyraena barracuda, in the West Indies and no other specimen has been obtained during the 75 years since then. The present collection, however, includes 3 females from a flying fish, No. 4 WILSON: PARASITIC COPEPODS eT Cypselurus callopterus (Giinther), at Charles Island, and thus con- firms Heller’s species, adding a new host and locality. The excel- lent description of the species in the reference given above was trans- lated by the present author and published in Proceedings U. S. Na- tional Museum, vol. 28, p. 602. The present specimens conform to that description in every particular. Caticus LATIFRoNS Wilson Caligus latifrons Wilson, Proc. U. S. Nat. Mus., vol. 28, p. 587, pl. 12, figs. 140-149. A single female was taken from the flying fish, Cypselurus cal- lopterus, in company with the 3 females of C. isonyx just mentioned. When the type of this species was described from the Woods Hole area the host was unknown, and it has so remained. The present specimen supplies a definite host as well as a new locality. Caticus tunaTus Wilson (plate 3, fig. 5) Caligus lunatus Wilson, Results Swedish Zool. Exped. to Egypt, No. 26B. p. 4, pl. 1, figs. 7-12; pl. 2, figs. 13-17. 1924. A single male was found on the gills of the yellowtail, Seriola dorsalis (Gill), at Bahia Honda, Panama. The original types were taken from another species, aurovittatus, of the same genus of fish captured in the Red Sea. Although this new locality is so far re- moved from the original one there is no doubt of the identity of the specimen. Cauicus MuTaBILIs Wilson Caligus mutabilis Wilson, Proc. U.S. Nat. Mus., vol. 28, p. 573, pl. 8, figs. 91-102. One male and four females were found on the skin of a Spanish mackerel, Scomberomorus maculatus, at White Friars, Mexico. This species has not before been found outside the Woods Hole area where it was originally discovered, and the host as well as the lo- cality is new. Cauicus aLiuncus Wilson (plate 3, figs. 4, a-f.) Caligus aliuncus Wilson, Proc. U. S. Nat. Mus., vol. 28, p. 576, pl. 9, figs. 103-111. A single male was taken from the skin of a yellowtail, Seriola dorsalis (Gill), and six males from the skin of an oceanic bonito, Gymnosarda pelamis (Linnaeus), both from Tagus Bay, Albermarle Island. Females of this species were found upon the skin of a bonito at the Dry Tortugas by Dr. Manter, but these are the first males to be discovered. The correspondence in the detail of the appendages 28 THE HANCOCK PACIFIC EXPEDITIONS VoL. 2 is amply sufficient to identify them as the two sexes of the same species even though the present locality is so far removed from the previous ones. Accordingly, one of these males has been selected to serve as the type of its sex and has been given Cat. No. 69865 U. S.N.M. and a description and figures are here given. Male. Carapace more than half the entire length and longer than wide, with nearly parallel sides; median posterior lobe half the width of the carapace and scarcely projecting behind the lateral lobes; the latter narrow and rather bluntly rounded. Free segment almost as wide as the genital segment, but much narrowed where it joins the carapace. Genital segment subovate, narrowed to the width of the abdomen posteriorly, with strongly convex sides. Two pairs of leg rudiments on the ventro-lateral margins nearer the posterior end. Abdomen two-segmented, the segments about equal in length and width; caudal rami as wide as long, each armed with 3 stout setae densely plumose. These setae afford excellent anchorage for various symbiotic organisms both vegetable and animal and are often dense- ly tufted with them. The appendages are similar to those of the female with these agreements. The stout terminal claw of the maxilliped shuts into a groove on the inner surface of the basal segt, the latter being con- siderably enlarged. This claw bears on its ventral surface a much larger accessory claw than that of the female, and a second acces- sory claw considerably smaller than the first. The basal segment of the third exopod has a stout flanged spine blunt at its tip, and the second and third segments also have spines along their outer mar- gins. The fourth leg is four-segmented with five spines; the four proximal spines have serrated flanges, the distal spine is without a flange. The proximal spine (on the second segment) has two flanges, the outer one more coarsely toothed than the inner; the next three spines have but a single flange, the size of the teeth diminishing so that those on the flange of the fourth spine are only one fourth as large as those on the first spine. There are rudiments of a fifth and sixth pair of legs on the sides of the genital segment near its poster- ior margin. Each of the fifth pair consists of a small papilla tipped with one long and densely plumose seta and three or four very short ones. Each of the sixth pair is made up of a single medium-sized seta attached directly to the segment with no papilla. Total length, 6 mm. Carapace, 3.50 mm, long, 2.95 mm. wide. No. 4 WILSON: PARASITIC COPEPODS 29 LEPEOPHTHEIRUS DISSIMULATUS Wilson Lepeophtheirus dissimulatus Wilson, Proc. U. S. Nat. Mus., vol. 28, p. 631, pl. 22. Seven females were taken from the skin of a yellow grouper, Mycteroperca olfax (Jenyns); one female from a small mackerel; one female from the gills of a second grouper, Cratinus agassixti Steindachner; three females and a male from the skin of a third grouper, Mycteroperca xenarcha, Jordan, all these four lots from Albermarle Island. Eight females and four males from the skin of a cabrilla, Paralabrax humeralis (Cuv. & Val.), at James Island. This species came originally from the Galapagos Islands, but with nothing to show its abundance. These new specimens from the same locality but from five new hosts show that the parasite is well dis- tributed among the groupers around the islands. ERGASILIDAE ARTACOLAX SAETIGER Wilson Artacolax saetiger Wilson, Proc. U. S. Nat. Mus. vol. 39, p. 361, pl. 51. A single female from the gills of a flying fish, Cypselurus callop- terus (Ginther), at Charles Island. The species was founded upon specimens obtained from a closely related flying fish at Woods Hole. This record adds a new host and a widely removed locality, and is the first to be made outside the original area. Bomotocuus ATTENUATUS Wilson Bomolochus attenuatus Wilson, Proc. U. S. Nat. Mus., vol. 44, p. 198, pl. 21. One female from the gills of the ringed swellfish, Chedichthys annulatus, at San Francisco, Ecuador; two females washed from the body cavity of a dredged Lophius at Bahia Honda, Panama; one fe- male from the gills of a small Lophius-like fish at Port Utria, Co- lombia. The species was originally found at Montego Bay, Jamaica, so that the present record adds two new hosts and three new lo- calities. DICHELESTHIIDAE Nemesis Patiwwa Wilson Nemesis pallida Wilson, Bull. 158, U. S. Nat. Mus., p. 464, pl. 33, figs. a-p. Two females from the gills of an unidentified shark at Bahia Honda, Panama. This species is very common upon the large sharks captured in the fish nets on Martha’s Vineyard but these are the first specimens to be reported outside of that locality. 30 THE HANCOCK PACIFIC EXPEDITIONS VOL. 2 LERNANTHROPUS MICROPTERYGIS Richiardi Lernanthropus micropterygis Richiardi, Atti del Soc. Toscana, vol. 4, p. 82. Two females from the gills of a Seriola sp. at Port Culebra, Costa Rica, and one female from the gills of Seriola dumerili at White Friars, Mexico. The species was originally obtained from the same host, but in the Mediterranean, and has been found on another species of Seriola in the Red Sea. We can now add the two localities given above. KRG@YERIA PAPILLIPES Wilson Kreeyeria papillipes Wilson, Bull. 158, U.S. Nat. Mus., p. 454, pl. 30, figs. a-i. Ten specimens including both sexes from the gills of an un- identified shark at Bahia Honda, Panama, and ten females from the gills of a gray shark at Socorro Island, Mexico. Like the Nemesis above, this parasite was common on the large sharks captured in the fish nets on Martha’s Vineyard, but has never before been re- ported from any other place. HAaATSCHEKIA OBLONGA Wilson Hatschekia oblonga Wilson, Proc. U.S. Nat. Mus., vol. 44, p. 242, pl. 42, figs. 222-226. A single female from the gills of a crevalle, Caranx hippos (Linn.), at Secas Island, Panama, and eight females from the gills of a Caulolatilis sp. at Tagus Cove, Albermarle Island. The species originally came from Montego Bay, Jamaica, and thus gains two new hosts and two new localities. EXPLANATION OF PLATE 3. Fic. 1. The fifth and genital segments and abdomen of a male Caligus balistae. Fic. 2. Dorsal view of a young female Caligus chorinemi 2 mm. in length. Fic. 3. The female of Caligus constrictus. a. Dorsal view. b. Side view of genital segment and abdomen, showing the attachment of the spermatophores. c. Ventral view of same. d. Maxilliped. e. Furca. f. First leg. g. Rudimentary endopod of same. h. Fourth leg. i. Third leg showing basal claw. Fic. 4. The male of Caligus aliuncus. a. Dorsal view. b. Maxilliped. c. Third leg showing flanged spine. d. Fourth leg. e. Proximal spine of same showing toothed flanges. Fic. The male of Caligus lunatus. wm PARASITIC COPEPODS WILSON: No. 4 ~ ey, de AAAS —< mea j if ola etl pe iif Us g REPORTS ON THE COLLECTIONS OBTAINED BY THE HANCOCK PACIFIC EXPEDITIONS OF VELERO III OFF THE COAST OF MEXICO, CENTRAL AMERICA, SOUTH AMERICA, AND GALAPAGOS ISLANDS IN 1932, in 1933, in 1934, mn 1935, In 1936, anv In 1937. SOME MONOGENETIC TREMATODES FROM THE GALAPAGOS ISLANDS AND THE NEIGHBORING PACIFIC By FRANK G. MESERVE Tue University oF SOUTHERN CALIFORNIA PUBLICATIONS Arran Hancock Paciric Expepirions Votume 2, Numser 5 IssuepD Marcu, 1938 THE UNIVERSITY OF SOUTHERN CALIFORNIA PRESS Los ANGELES, CALIFORNIA TABLE OF CONTENTS INTRODUCTION DESCRIPTIONS OF SPECIES CAPSALIDAE Benedenia isabellae, new species Benedenia adenea, new species Benedenia anadenea, new species Entobdelia muelleri, new species Encotyllabe pagrosomi MacCallum, 1917 DicimopHorIpArE Dichidophora caulolatili, new species Heterobothrium ecuadori, new species Heterobothrium galapagensis, new species HEXOsTOMIDAE Hexostoma euthynnt, new species MazocraEIDAE Maxocraes macracanthum, new species MicrocotTyLipAE Microcotyle priacanthi, new species Gotocotyla acanthocybii, new genus, new species Gotocotyla elagatis, new species Thoracocotyle paradoxica, new species . Axine oligoplitis, new species Axine seriolae, new species Axine elongata, new species Axine aberrans Goto, 1894 Pseudaxine mexicana, new species Protomicrocotyle pacifica, new species Cestracolpa cypseluri, new genus, new species Cestracolpa yamagutti, new species SUMMARY AND CONCLUSIONS LITERATURE CITED Page i: Yat in 7 , NI Ske tart tga " oR i” E iE : ek i ee (ay i] i : aig ath 7 aati 7 Oi ’ yi yaw >) Te ee eee hd ; i ' opi 4 ' 11, aug oe 7 LG st’ _ | ) ‘wittil _s vin) ’ a) Ls uDiay shen ubttel A 7 ; " 7 7 | i 2 Ae / ih \ | | Ov» 17 18 i ' Fiance seh r rs To. - i ugee : + en hk . i - help we Go 1 oof, A , | 2 peal - Pm ey SOME MONOGENETIC TREMATODES FROM THE GALAPAGOS ISLANDS AND THE NEIGHBORING PACIFIC* (Wirth Seven Prates) Frank G. MESERVE University of Nebraska This paper is an account and description of new species of ecto- parasitic trematodes found on marine fishes in the south Pacific in the region of the Galapagos Islands. The animals were collected and preserved by Professor H. W. Manter, who was a member of the G. Allan Hancock Expedition to the Galapagos Islands in 1934. All the specimens were collected in January, February, and early March. In the preliminary report Manter (1934) states: Over 500 marine fish, representing approximately 100 species, were examined for parasites. Approximately 100 species of trematodes were collected, 80 per cent of the species of fish and 43 per cent of the individuals examined being infected. Approximately 20 per cent of the trematodes collected were Monogenea. The writer wishes to extend acknowledgment and express sincere thanks to Professor H. W. Manter, under whose direction these studies were made. All descriptions were made from specimens col- lected by him with the exception of type material of Protomicroco- tyle which was made available through the courtesy of Doctor E. W. Price. Particularly valuable in this research was the loan of books and reprints from Professor Manter’s personal library. The writer is also indebted to Professor T. J. Fitzpatrick of the University of Nebraska for his valuable aid in securing periodicals and reprints from other libraries. Special acknowledgment is given to Doctor E. W. Price of the Bureau of Animal Husbandry, U. S. Depart- ment of Agriculture, for the loan of type material of Protomicrocotyle mirabile (MacCallum, 1918) from the United States National Mu- seum. He also reviewed this paper and made some corrections before it went to the publisher. Sincere gratitude is also expressed to Pro- fessor D. D. Whitney of the University of Nebraska who co-operated in many ways and expressed a keen and kindly interest throughout these studies. * Studies from the Zoological Laboratories, University of Nebraska, No. 195. [ 31] 32 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 No new methods of technique were used. The animals were killed in formol-alcohol-acetic acid solution (formalin 614 parts, 50 per cent alcohol 100 parts, glacial acetic acid 2% parts) under a cover glass to flatten the specimen. After several hours the killing solution was removed and the specimens were preserved in 70 per cent alcohol. Specimens were stained in Delafield’s haematoxylin. Some were counterstained with orange G, eosin, or erythrosin. Serial sec- tions were made except where there were few specimens. Toto © mounts were cleared in cedar oil and serial sections in xylol. All were mounted in balsam. Identification of fish hosts of these trematodes is often incom- plete. Unless otherwise indicated the fishes were indentified by H. W. Manter and Dr. Waldo Schmitt. Because no specialist on fishes was available at the time of collecting, these identifications cannot be considered as authoritative. However, an identification thus made is used only after reasonable satisfaction that it is correct. Some specimens, especially of the smaller fishes, were sent to the United States National Museum and kindly identified by Dr. G. S. Myers. These identifications are indicated in the text. The names of all fish hosts, as far as identified, are as listed in Jordan, Evermann and Clark’s check list (1930). Types of all new species will be deposited in the United States National Museum at Washington, D.C. Paratypes will be located at The University of Southern California. The recent comprehensive studies of Price (1937, 1937a) on the Monogenea make extensive history and bibliographies unnecessary. The descriptions in this paper are condensed to serve as specific diagnoses. Famity: CAPSALIDAE Barn, 1853 SUBFAMILY: BENEDENIINAE JoHNsTON, 1931 Monticelli (1903) in a revision of the genus Epibdella Blain- ville, 1827* divided it into those with true suckers, subgenus Bene- denia Odhner, 1905 and those with pseudosuckers, subgenus Phylline *“The date 1828 is usually quoted, but Sherborn (Index Animalium, pt. ix., 1926, p. 2169) recorded the genus as having been published by Blainville in Dict. Sci. Nat., vol. xlvii., 1827, p. 269, and in vol. lvii., 1828, p. 567.”—[from Johnston (1929) ]. No. 5 MESERVE: MONOGENETIC TREMATODES 33 Oken, 1815 (P. hippoglossi). Phylline was shown by Odhner (1905) to be a synonym of 7'ristomum maculatum Rudolphi, 1819 (which in turn is now considered a synonym of Capsala). The type of Epibdella is £. hippoglossi (Mueller, 1776) which possesses pseudo- suckers. Odhner (1905) elevated the subgenus Benedenia to generic rank, resulting in two genera, Epibdella with pseudosuckers and Benedenia with true suckers. Johnston (1929) points out that Epib- della should be submerged as a synonym of Entobdella. Johnston (1929) says: In 1817 Cuvier, in his “Le Régne Animal,” vol. 4, erected the genus T7ristoma, describing and figuring one species, 7. coccineum. Next year Lamarck (1818, 295) gave a summary of Phylline, mentioned the synonymy of P. hippoglossi, and stated his belief that the parasites were related to Polystoma instead of Annelids (leeches), where they had been allotted. He also referred to Blainville’s manuscript name, Entobdella, for the genus, but retained Oken’s Phylline. The reference was quoted erroneously by Braun (1889) as appearing in Lamarck’s vol. 1, p. 444, and subse- quently (1890, 518) he indicated the genus with the date 1815 (when vol. 1 appeared) as a synonym of E£pibdella. Stiles and Hassall (1908, 251) credit Entob- della to Audouin 1828, whereas Agassiz (1845) and Scudder (1884), in their respective Nomenclatores Zoologici, attribute it to Blainville, but without mentioning a date. Sherborn, in his Index Animalium, gives the correct date (1818) for Entob- della (Blainville MS.) Lamarck. It was not mentioned by Rudolphi (1819), and has remained practically unrecognized since. Yamaguti (1937) uses the genus name Epibdella with two sub- genera, Epibdella and Benedenia, and classifies it in the family Cap- salidae. He does not explain his adoption of these names but evi- dently does not follow either Odhner or Johnston. The subgenus Epibdella seems to possess anterior suckers and the subgenus Bene- denia seems to possess anterior suckers together with the folds of “an anterior adhesive organ,” thus corresponding to the genera Benedenia and Pseudobenedenia, respectively, of Johnston (1931). Johnston (1931) in a revision of the family Capsalidae Baird, 1853 (Tristomidae Taschenberg, 1879) names the subfamily Cap- salinae Johnston, 1931 (Tristominae Monticelli, 1903) with Capsala (Tristoma) as the type genus characterized by numerous radii in the posterior haptor; the subfamily Nitzschinae Johnston, 1931 with Nitzschia von Baer as the type genus characterized by numerous testes and a median genital pore; Ancyrocotylinae Monticelli, 1902; Benedeniinae Johnston, 1931. Johnston (1931) gives the following diagnosis of the subfamily Benedentunae: 34 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 Capsalidae with large stalked posterior suckers, provided with typically, three pairs of hooks, the second pair largest, the third smallest (or perhaps absent), but without septa dividing it into loculi; either with anterior glandular organs (Entob- della) or with anterior suckers (Benedenia), or with both (Pseudobenedenia); with two testes lying side by side. I include the following subfamilies under the family Capsalidae: Capsalinae Johnston, 1931, Nitzschinae Johnston, 1931, and Bene- denunae Johnston, 1931. The genera of the subfamily Benedentinae may be distinguished as follows: 1 (2) Lateral. intestinal. branches absent...) eee Ancyrocotyle Parona and Perugia, 1903 2 (1): Lateral’ intestinal. branches present::2..212 Dee 3 3 (4) True anterior suckers absent; anterior adhesive ‘organs present. io!) J) 20) 2) eee Entobdella Blainville, 1818* 4 (3). True anterior suckers ‘present. ...2...2-<-.- 5. 5 5 (6) Anterior adhesive organs presents.:2._..-.2 ee Pseudobenedenia Johnston, 1931 6°(5), Anterior -adhesive organs -absent:.4._£ <2). ee Benedenia Odhner, 1905 According to Johnston (1931, p. 95) Ancyrocotylinae should be restricted to include Ancyrocotyle with a single preovarian testis and the absence of lateral branches to the intestinal crura. Price (1934), however, places Ancyrocotyle in the subfamily Benedeniinae. It was suggested by him that, due to the fact that the material of Ancyrocotyle vallei was in poor condition, there might have been an error in interpreting the preovarian testis. 4. bartschi Price, 1934 has two testes posterior to the ovary. In this paper, the genus name Benedenia is accepted foie those forms with true anterior suckers. The following species of Benedenia have been described: 1. B. derzhavim (Layman, 1930) n. comb. on Sebastodes schle- gelii. *Lamarck (1818) in referring to Phylline Oken states: “Ce genre est établi par M. Ochen, sous le nom que nous lui conservons, et néanmons M. de Blainville, que l’avait déja reconnu, lui assigna celui de Entobdella, dans ses manuscrits.” No. 5 MESERVE: MONOGENETIC TREMATODES 35 2. B. epinepheli (Yamaguti, 1937) n. comb. on Epinephelus akaara. 3. B. hendorffii (von Linstow, 1889) on Sciaena aquilla. 4. B. ishtkawae (Goto, 1894) on Lethrinus sp. 5. B. macrocolpa (Liihe, 1906) on Rhinoptera javanica. 6 . B. melleni (MacCallum, 1927) n. comb. on Spherotdes annu- latus, etc. . B. monticell (Parona and Perugia, 1895) on Mugil auratus. . B. ovata (Goto, 1894) on Anthias schlegeli. } B. seriolae (Yamaguti, 1934) n. comb. on Sebastodes aureo- uittata. 10. B. scitaenae (van Beneden, 1858) on Sciaena aquilla. 11. B. sebastodis (Yamaguti, 1934) n. comb. on Sebastodes inermis. 12. B. seku (Yamaguti, 1937) n. comb. on Pagrosomus unicolor. | \O 00 Benedenia isabellae, new species (Plate 4, figs. 1-2) Host: Unidentified, spotted, grouper-like fish Location: Gills Locality: Isabel Island, Mexico Number: 5 specimens Body elongated oval, 3.282 to 5.113 mm. in length by 1.820 to 2.5 mm. in greatest width. Posterior haptor circular, not indented, 0.848 to 1.56 mm. in diameter, with irregularly notched, relatively wide marginal membrane. The anterior pair of hooks 0.118 to 0.424 mm. in length, straight, sharply pointed at one end, truncated at the other end. Middle pair of hooks 0.271 to 0.424 mm. in length, tairly stout, straight except for a recurved point. Posterior pair of hooks 0.08 to 0.10 mm. in length, with fine, recurved point. Larval hooks not seen. Anterior suckers elliptical, with slightly elevated margins but without marginal membrane, 0.220 to 0.339 mm. in length by 0.305 to 0.390 mm. in width. Oral sucker broader than long, 0.220 to 0.339 mm. in length by 0.388 to 0.557 mm. in width, indented to form two to five lobes. Esophagus short, intestinal limbs with lateral branches. Testes approximately in mid-body, side by side and close together, with slightly lobed or crenate margin, longer than wide, 0.736 to 0.996 mm. by 0.520 to 0.693 mm., pierced by sixteen to twenty dorso-ventral muscles. Posterior to testes are two 36 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 small, smooth, elliptical bodies, broader than long, 0.056 to 0.067 mm. in length by 0.101 to 0.118 mm. in width. Similar structures were first described by Goto (1894) in Benedenia ovata. Their func- tion is problematic. The name glands of Goto is proposed for them. The cirrus sac extends less than halfway between oral sucker and ovary. Prostate glands fan-shaped, opposite cirrus sac, extending nearly to lateral edges of body and posteriorly almost to the ovary. The genital pore to the left opposite the middle of the oral sucker. Ovary median, partly pretesticular, partly between the anterior edges of the testes, elliptical, 0.305 to 0.557 mm. in length by 0.237 to 0.339 mm. in width, and pierced by eleven dorso-ventral muscles. Seminal receptacle intraovarian. Vitellaria extending from the oral sucker to the posterior end of the body. Yolk reservoir just anterior to ovary, transversely extended, constricted in middle. Vagina not seen. Egg triangular in surface view, 0.101 by 0.130 mm. with short, curved, stout appendage at one pole and a long, slender filament at the other. Comparisons. B. isabellae differs from B. ishikawae in possessing lobed testes and glands of Goto; from B. ovata in possessing lobed testes and nonindented haptor; from B. epinepheli in possessing lobed testes, perforated testes, more posterior genital pore as well as different hooks. It is most similar to B. melleni but has larger, more elongated, more lobed testes with more numerous perforations, with more expanded prostate glands, and glands of Goto. This species is named after its geographic location, Isabel Island, Mexico. Benedenia adenea, new species (Plate 4, figs. 3-4) Host: Mycteroperca sp. Location: Gills Locality: Socorro Island, Mexico Number: 5 Body elongated oval, 1.7 to 2.9 mm. in length by 1.256 to 1.773 mm. in greatest width. Posterior haptor circular, with indentations which form five lobes, 0.678 to 0.953 mm. in diameter, with irregu- larly notched, relatively wide marginal membrane. The anterior pair of hooks 0.084 to 0.118 mm., strong with relatively long projecting piece slightly oblique and posterior to base of hook, straight with points anterior in floor of haptor. Middle pair of hooks 0.169 to No. 5 MESERVE: MONOGENETIC TREMATODES 37 0.237 mm. in length, relatively long and strong, sharp recurved points projecting anteriorly at the two indentations in posterior border of haptor. Posterior pair of hooks 0.050 to 0.084 mm. in length, straight except at very fine recurved tips. Larval hooks present 0.040 mm. in length. Anterior suckers elliptical, without marginal membrane, broader than long, 0.101 to 0.185 mm. in length by 0.117 to 0.254 mm. in width. Oral sucker broader than long, 0.169 to 0.332 mm. in length by 0.204 to 0.390 mm. in width, deeply five-lobed. Esophagus short, intestinal limbs with lateral branches. Testes approximately in mid-body, side by side and close together, smooth, unlobed, slightly longer than broad, 0.339 to 0.661 mm. in length by 0.288 to 0.491 mm. in width, pierced by twelve to seventeen dorso-ventral muscles. Posterior to testes are two kidney-bean shaped glands of Goto, broader than long, 0.03 mm. in length by 0.118 mm. in width, concave borders anterior and of same contour as posterior border of testes. The cirrus sac extends less than halfway between oral sucker and ovary. Prostate glands fan-shaped, opposite cirrus sac, extending nearly to lateral edges of body and posteriorly over halfway from oral sucker to ovary. The genital pore to left of oral sucker and an- terior to anterior border of oral sucker. Ovary median, partly pre- testicular, partly between anterior edges of testes, smooth, globular, unlobed, 0.152 to 0.305 mm. in length by 0.169 to 0.322 in width. Seminal receptacle intraovarian. Vitellaria coarsely acinous extend- ing from anterior suckers to posterior end and lateral to the sides. Yolk reservoir just anterior to ovary, one and one-half times the width of the ovary, over twice as wide as long and receives vitelline ducts from its lateral, anterior, and posterior borders. Vagina not seen. Egg triangular in outline appearing pyramidal from the ventral side, 0.092 mm. in length by 0.125 mm. in width, polar filament and appendage absent, lower border has thick ridge of shell material which also extends up middle of ventral side over halfway to an- terior end of egg. B. adenea is most similar to B. isabellae but differs in possessing smooth testes, more elongated glands of Goto, smaller size, more anterior genital pore, and more spherical ovary. It differs from B. ovata in possessing elongated glands of Goto and differently shaped hooks. B. ishikawae differs in lacking glands of Goto. 38 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 The species name (denea-gland) is derived from the fact that it possesses glands of Goto posterior to the testes. Benedenia anadenea, new species (Plate 4, figs. 5-8) Host: Mycteroperca sp. Location: Gills Locality: Socorro Island, Mexico Number: 12 Body elongated oval, 2.1 to 3.99 mm. in length by 1.56 to 2.16 mm. in greatest width. Posterior haptor circular and strongly five- lobed, 0.076 to 1.12 mm. in diameter, broad unnotched marginal membrane. The anterior pair of hooks 0.067 to 0.118 mm. in length, straight with sharp points directed anteriorly. Middle pair of hooks 0.118 to 0.288 mm. in length, strong, arcuate with strongly recurved points directed anteriorly. Posterior pair of hooks 0.048 mm. in length, relatively slender with recurved points directed anteriorly. Larval hooks 0.028 to 0.080 mm. in length. Anterior suckers ellipti- cal, without marginal membrane, broader than long, 0.16 to 0.20 mm. in length by 0.16 to 0.27 mm. wide. Oral sucker broader than long 0.18 to 0.25 mm. in length by 0.30 to 0.42 mm. in width, five- lobed with slight indentations. Esophagus short, intestinal limbs with lateral branches. Testes approximately in mid-body, side by side and close together, smooth, unlobed, slightly longer than broad, 0.47 to 0.75 mm. in length by 0.50 to 0.54 mm. in width, pierced by eleven to seventeen dorso-ventral muscles. Glands of Goto absent. Cirrus sac bulbous, twice as long as wide, posterior to oral sucker extending halfway between oral sucker and ovary. Prostate glands fan-shaped opposite cirrus sac, extending nearly to lateral edges of body and posteriorly over halfway from oral sucker to ovary. The genital pore to left of oral sucker, anterior to anterior border of oral sucker. Ovary median, partly between anterior edges of testes, smooth, globular, unlobed, slightly broader than long, 0.169 to 0.254 mm. in length by 0.169 to 0.288 mm. in width. Seminal receptacle intraovarian. Vitellaria extend from lateral borders of anterior suckers to posterior end of animal and lateral to sides. Yolk reservoir not visible. Vagina not seen. Egg triangular in surface view, 0.092 No. 5 MESERVE: MONOGENETIC TREMATODES 39 mm. in length by 0.112 mm. in width, single polar filament extends posteriorly, 0.20 mm. in length. Discussion. The following observations on the histology of the posterior haptor may be of some interest. Unicellular high columnar gland cells are present in the posterior haptor. They have an almost spherical nucleus slightly anterior to the center of the cell with chro- matin granules aggregated around the nuclear wall. The diameter of the nucleus is over one half the width of the cell. A large area of secretory granules lies just anterior to the nucleus toward the border of the cell which is toward the border of the cell on inside of haptor. Other nonsecretory cells of the haptor are tall, columnar, and slightly wider than the gland cells. They have large elliptical nuclei at their bases. The chromatin is scattered in a network throughout the nuc- leus. The nucleolus was not visible. The gland cells have a heavily staining nucleolus toward one end of the nucleus. Comparisons. This species is very similar to B. melleni, which has testes which are smaller, lobed, with two to ten dorso-ventral muscles as compared with larger, smooth testes with eleven to seventeen dorso-ventral muscles. A prostate gland is present in both but is more compact and fan-shaped in B. anadenea. B. anadenea differs from B. adenea in not possessing glands of Goto and in having larger hooks. The name anadenea is given to this species since glands of Goto are absent. Genus: ENTOBDELLA BiaINviLte, 1818 As previously stated the genus name Entobdella is used in this paper for Benedeniinae with false suckers. The following species of the genus Entobdella have been previ- ously described: . bumpsii (Linton, 1900) on Lasyatis centrura. . convoluta (Yamaguti, 1937) n. comb. on Epinephelus akaara. . diadema (Monticelli, 1902) on Solea vulgaris. . hippoglossi (Mueller, 1776), the type species on Spheroides annulatus, etc. . producta (von Linstow, 1904) on Solea vulgaris. . solea (van Ben. and Hesse, 1863) on Solea vulgaris. .squamula (Heath, 1902) on Paralichthys californicus. . steingréveri (Cohn, 1916) on unidentified fish. Saha baa 40 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 Entobdella muelleri, new species (Plate 4, fig. 9) Host: Cratinus agassizi Steindachner* Location: Gills Locality: Tagus Cove, Albemarle Island, Galapagos Islands Number: 1 Body elongated oval, more than twice as long as wide, 4.116 mm. long by 1.603 mm. in greatest width. Posterior haptor circular and unlobed, 1.083 mm. in diameter with narrow marginal membrane. Anterior pair of hooks 0.176 mm. in length, straight, relatively strong. Middle pair of hooks large and powerful, 0.50 mm. in length, arcuate with recurved points. Posterior pair of hooks 0.100 mm. in length, straight, with short, fine recurved points. Larval hooks 0.020 mm. in length. Anterior pseudosuckers 0.508 mm. in length, ellipti- cal, slightly broader than long with thin, flat crenate margins. Oral sucker weakly five-lobed, slightly broader than long, 0.440 mm. in width. Pharynx present and can be seen in ventral view through mouth opening as two kidney-shaped muscular structures close to- gether with concave sides toward each other. Esophagus probably present but not visible. Intestinal limbs with lateral branches, not united posteriorly. Testes approximately in mid-body, side by side and close together, smooth, unlobed, slightly longer than broad, small, 0.339 mm. in length by 0.235 mm. in width, each pierced by nine dorso-ventral muscles. Glands of Goto 0.080 mm. in length by 0.048 mm. in width, elliptical, longer than broad, tipped obliquely toward each other anteriorly and located a relatively great distance posterior to testes. Cirrus sac bulbous, approximately twice as long as wide, just posterior to left of oral sucker, not quite one third of distance from oral sucker to ovary. Genital pore to left of oral sucker opposite mouth approximately two thirds distance from posterior to anterior border of oral sucker. Ovary elliptical, smooth, broader than long, relatively far anterior to testes, 0.305 mm. in length by 0.339 mm. in width, smaller than testes. Seminal receptacle intra- ovarian. Vitellaria extend from anterior suckers to posterior end of animal. Yolk reservoir anterior to ovary, three times as long as broad, its width approximately equal to width of ovary, slightly * For the identification of this host the writer is indebted to Dr. G. S. Myers of the United States National Museum. No. 5 MESERVE: MONOGENETIC TREMATODES 41 constricted in middle. Vagina not seen. No mature egg present in type specimen. Comparisons. E. muelleri differs from E. hippoglossi in possess- ing no papillae in posterior haptor. It differs from E. soleae in having no papillae on the body. It is more similar to E. steingréveri but its posterior hooks are different. The posterior hooks of E. steingrovert are split almost their whole length. The posterior hooks of E, muelleri are not split. E. muelleri has glands of Goto which are absent in E. steingréveri and differs from E. convoluta which has no glands of Goto, possesses an anterior adhesive hood connecting the pseudo- suckers and an extremely long cirrus pouch. Since there is only one specimen, the type, the species is pro- visional. E. muelleri is named after Mueller, who named the type species of the genus. ENCOTYLLABE PAGROsOMI MacCallum, 1917 (Plate 5, figs. 10-12) Host: Caulolatilus sp. Location: Gills Locality: James Island, Galapagos Islands Number: 1 The following species of Encotyllabe Diesing, 1850 have been described to date: EF. nordmanni Dies., 1850, E. pagelli van Ben. and Hesse, 1863, E. pagrosomi MacCal., 1917, E. paronae Mont., 1907, E. spart Yamaguti, 1934, E. vallei Mont., 1907 and E£. lintoni Monti- celli, 1909. Only one specimen was collected for which reason it is provision- ally identified as E. pagrosomi. Price (1937) has redescribed E. pagrosomi and the comparisons made in this paper are based on his redescription. MacCallum’s four specimens were from the “mouth and throat” of Pagrosomus auratus (Houttuyn). Price (1937) gives the follow- ing measurements for MacCallum’s material: 5.0 to 5.4 mm. in length; 1.4 mm. in width. The specimen of the author is 2.166 mm. in length by 1.266 mm. at its greatest width. Its large hooks measure 0.254 mm. as compared to 0.360 to 0.380 mm. The width of the large hooks is 0.080 mm. which is one half the length of MacCal- 42 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 lum’s (0.152 to 0.172 mm.). The small hooks are approximately the same size (0.028 as compared to 0.030 mm.). Other structures are correspondingly smaller. Famity: DICLIDOPHORIDAE Cerrontarnge, 1896 SUBFAMILY: DICLIDOPHORINAE CERFONTAINE, 1896 Price (1936) includes Diclidophora in a new superfamily Dicli- dophoroidea and retains it in the order Polypisthocotylea Odhner. He removes D. affinis Linton, 1901 and D. cynoscioni MacCallum, 1907 from the genus Diclidophora and places them in Heterobothrium Cerfontaine. The genera of the subfamily Diclidophorinae can be separated by the following key. I (2) Cirrus hooks. single.:/2.2...2242_. Diclidophoropsis Gallien 2. (1): Cisrus: hooks: double.o8 20. 312.2 8 2.2sscccuct chee ee 3 3. (4): Posterior suckers: sessile. .....0::8..20-5-<2scc-4.. eee 7 4 (3) Posterior suckers. on pedicels...1.2:4.<..- eee ee 5 5 (6) Three pairs of pedicellate suckers and a long median posterior extension of body............ Pedocotyle MacCallum 6 (5) Four pairs pedicellate suckers, no posterior extension 6 ide] 00.68 ese Ne sae Rae Diclidophora Diesing 7 (8) Testes numerous, extending from genital pore to first pair of posterior suckers.......... Cyclobothrium Cerfontaine 8 .(7) Testes few, posterior to ovary 22.22.21:4...3 eee Heterobothrium Cerfontaine The following seven species of Diclidophora have been described to date: D. chrysophryi (v. Ben. and Hess., 1863) v. Ben. and Hess., 1895 on Chysophrys aurata. D. elongata Goto, 1894 on Pagrus tumifrons and Cymothoa sp. D. labracis Cerfontaine, 1896 on Labrax lupus. D. merlangi (Kuhn, 1828) Kryer, 1838 on Merlangus vulgaris. D. neomaenis MacCallum, 1917 on Prionotus carolinus. D. smaris (Ijima, 1894) Goto, 1894 on Smaris vulgaris. D. taschenbergii Parona and Perugia, 1889 on Sargus rondeletit. No. 5 MESERVE: MONOGENETIC TREMATODES 43 Diclidophora caulolatili, new species (Plate 5, figs. 13-15) Host: Caulolatilus princeps (Jenyns) Location: Gills Locality: Tagus Cove, Albemarle and Chatham Islands, Galapagos Islands Number: 2 Body lanceolate, somewhat pointed and tapering at the anterior end, 4.506 to 5.970 mm. in length by 0.784 to 1.170 mm. at greatest width. Posterior haptor approximately one third total body length with eight elliptical posterior suckers on tips of relatively long pedi- cels which are approximately equal in length. Posterior pair of suckers approximately one half diameter of other three pairs. An- terior pair of posterior suckers 0.339 by 0.373 mm. in length by 0.339 to 0.407 mm. in width, chitinous skeleton (fig. 14) complex with eight chitinous pieces and four spines, eight pieces, one ventral, broad, Y-shaped piece, one pair of short pieces lateral to Y-shaped rod, one pair joining these and imbedded in the lateral wall of the sucker, a single upright piece with a pair of curved lateral rods joining it at the distal end; four spines with bulbous bases and fine recurved points at top of sucker with faces imbedded in sucker wall and having exposed sharp points. Anterior suckers relatively large, without membranous septa, elliptical, longer than broad, 0.127 to 0.169 mm. in length by 0.084 to 0.135 mm. in width. Pharynx bulb- shaped, longer than wide, 0.080 to 0.120 mm. in length by 0.044 by 0.076 mm. in width. Esophagus relatively long and slender, bifur- cating just in front of genital pore to form intestinal limbs with lateral branches. Testes smooth, almost spherical, extending from ovary to posterior haptor, fifty-six to sixty-five in number. Cirrus armed with thirteen double recurved hooks. Cirrus hooks 0.012 to 0.016 mm. in length. Genital pore just posterior to bifurcation of esophagus well forward in the anterior part of the worm on ventral side in mid-line. The distance from anterior end of worm to genital pore is 0.271 to 0.424 mm. Size of opening of genital pore is 0.02 mm., diameter of outer rim 0.06 mm. Ovary slightly to left side of mid-line in middle part of body proper, vertical arm approximately twice diameter of horizontal arm, posterior arm at right angles to upright vertical arm and bent in form of a C with ends open and directed posteriorly. Seminal receptacle large to right of ovary, C- 44 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 shaped and sac-like with open ends of C to left, lower arm of C directed anteriorly (fig. 13), approximately length and diameter of lower horizontal arm of ovary. Genitointestinal canal present. Vitel- laria separated anteriorly extending from genital pore to middle of posterior haptor where they unite. Two vitelline ducts unite in mid- line about one third distance from genital pore to ovary forming common yolk duct which extends straight posteriorly turning to right at lower end before joining oviduct. No mature egg present. Comparisons. D. caulolatili is most like D. neomaenis. In both species the posterior pair of suckers is smaller than the anterior pairs. D. neomaenis is larger (9.0 mm. in length as compared to 4.5 to 4.9 mm.) and has twenty-five testes and twelve cirrus hooks, whereas D. caulolatili has fifty-six to sixty-five testes and thirteen cirrus hooks. D. caulolatili is named after the genus of the host, Caulolatilus. Heterobothrium ecuadori, new species (Plate 5, figs. 16-19) Host: Cheilichthys annulatus (Jenyns) Location: Gills Locality: Tagus Cove, Albemarle Island, Galapagos Is- lands, San Francisco, Ecuador Number: 4 Body lanceolate, thin, flat, and left side with pronounced greater curvature, 2.903 to 3.466 mm. in length by 0.866 to 1.256 mm. in greatest width, three times as long as wide. Posterior haptor not separated from body proper, approximately one fourth total body length, 0.763 to 1.017 mm. in length by 0.915 to 1.213 mm. in greatest width. Four pairs of posterior suckers arranged in the shape of a horseshoe, four on each side with open end of horseshoe pointing anteriorly, elliptical, slightly broader than long, 0.152 to 0.203 mm. in length by 0.186 to 0.271 mm. in width. Chitinous skeleton (fig. 19) consists of two lateral pieces on each side and a central piece with short, T-shaped distal end. Mouth slightly sub- terminal leading into large mouth cavity. Anterior mouth suckers large, elliptical, longer than wide, 0.169 to 0.220 mm. in length by 0.118 to 0.186 mm. in width. Pharynx large, elliptical, slightly wider than long, 0.084 to 0.118 mm. in length to 0.085 to 0.120 mm. in width. Esophagus very short without lateral branches. Intestinal No. 5 MESERVE: MONOGENETIC TREMATODES 45 limbs with lateral branches, unite at posterior end of worm. Testes in median line posterior to ovary, twenty-seven to forty in number, smooth, unlobed, closely packed and irregular in shape. Cirrus spherical with fourteen to sixteen strong double hooks arranged in a circle with powerful sucker just below hooks. Diameter of cirrus 0.116 to 0.114 mm. Length of cirrus hooks 0.038 to 0.048 mm. Genital pore well forward in mid-line about posterior part of first eighth of animal, width of opening 0.020 mm. surrounded by cir- cular to elliptical rim 0.036 to 0.040 mm. in diameter. Ovary situated in mid-line in posterior part of first third of animal, ovarian region 0.254 to 0.407 mm. in length, diameter of ovary at widest part 0.084 to 0.135 mm., U-shaped with open end to right, lower arm smaller in diameter with pronounced enlargement at lower end. Vagina absent. Genitointestinal canal present. Vitelline ducts unite at upper end of ovary to form large yolk duct. Vitellaria extend from genital pore to haptor, separated in front, united behind. Eggs elongated oval with short polar knob at anterior end and long filament at pos- terior end, 0.152 to 0.169 mm. in length by 0.052 to 0.076 mm. in width, length of filament 0.200 to 0.203 mm. Comparisons. H. ecuadori is similar to H. tetrodonis (Goto, 1894) but is much smaller, 2.9 to 3.4 mm. in length as compared to 5.0 to 15.0 mm., has twelve to fourteen cirrus hooks as compared to ten and the vitellaria extend to the posterior haptor as compared to vitellaria being absent in posterior half of H. tetrodonts. H. ecuadori is named after its geographic location, Ecuador. Heterobothrium galapagensis, new species (Plate 5, figs. 20-21) Host: Paranthias furcifer (Cuv. and Val.) Location: Gills Locality: Tagus Cove, Albemarle Island, Galapagos Is- lands Number: 1 Body thin and flat, anterior end bluntly pointed, 1.560 mm. in length by 0.457 mm. in greatest width at middle of body, left side of body with pronounced outward curve, tapering anteriorly and posteriorly from the middle. Approximately same width across an- terior end in front of haptor. Posterior haptor relatively short and broad, 0.254 mm. in length by 0.542 in width. Four posterior suckers 46 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 present, the rest apparently having been torn off, each sucker ellipti- cal, slightly longer than wide, 0.088 to 0.092 mm. in length by 0.072 to 0.076 mm. in width. Anterior suckers large with membran- ous septa, elliptical, longer than wide, 0.100 mm. in length by 0.096 mm. in width. Pharynx 0.056 mm. in length by 0.036 mm. in width, bulb-shaped, longer than wide. Esophagus relatively short, intestinal limbs with lateral branches. Testes relatively large extending from middle of ovarian region to posterior haptor, elliptical to slightly angular, smooth, unlobed, thirty-seven in number. Vas deferens rela- tively wide and tortuous. Cirrus bulb-shaped with six small double hooks. Cirrus 0.048 mm. in diameter. Cirrus hooks 0.012 mm. in length. Genital pore well forward in mid-line at level of anterior border of vitellaria. Ovary approximately in middle of body in mid- line, in shape of inverted U tilted obliquely to left with open end of U pointing posteriorly, lower arm broader than upper arm, length of ovarian region 0.220 mm. in length by 0.203 mm. in width. Ovi- duct arises from lower end of right arm of ovary. Vitelline ducts arise from vitellaria at about level of middle of ovary. Common vitelline duct relatively broad, passing obliquely posterior to right of ovary. Vitelline glands coarsely acinous, from genital pore to hap- tor, separated in front, slightly confluent at posterior end. Uterus relatively wide, almost straight. No mature egg present. Discussion, Since there was only one specimen this species is provisional. Heterobothrium normally has eight suckers. H. gala- pagensis has only four. It is quite obvious that there is a vacant space on the right side of the haptor where, no doubt, was once a sucker. If this missing sucker were present there would still be only five. Since the other generic characters are typical of the genus it is provisionally placed in Heterobothrium. Comparisons. H. galapagensis differs from H. tetrodonis (Goto) and H. ecuadori in the shape of the body which is more or less dis- tinctly divided into three regions, an anterior portion in front of the genital pore separated by a slight constriction, the middle part of the body which tapers toward the haptor, and the posterior haptor which is broad and distinctly marked off from the body. The cirrus of this species has only six hooks, H. tetrodomis has ten, and H. ecuadori has twelve to fourteen. H. galapagensis gets its name from its geographic location, the Galapagos Islands. No. 5 MESERVE: MONOGENETIC TREMATODES 47 Famity: HEXOSTOMATIDAE Price, 1936 Hexostoma euthynni, new species (Plate 6, figs. 22-24) Host: Euthynnus alletteratus (Rafinesque) Location: Gills Locality: James Island, Galapagos Islands Number: 1 Body elongated, tapering anteriorly from ovary, anterior end pointed, constricted at middle of body proper posterior to ovary, 5.853 mm. in length by 0.953 mm. in width. Posterior haptor large, 0.953 mm. in length by 1.30 mm. in width, slightly wider than the widest part of body. Eight large posterior suckers, elliptical, broader than long, 0.203 mm. in length by 0.339 mm. in width, arranged somewhat in form of a horseshoe. Each sucker has three heavy X- shaped, chitinous, skeletal pieces imbedded longitudinally in its walls, middle skeletal piece longer, imbedded in septum which divides sucker into two parts; one X-shaped skeletal piece imbedded in wall in each side of sucker. Two pairs of hooks at posterior end of animal; anterior pair larger with a base which is imbedded and parallel to the rest of the hook which is straight and points posteri- orly, 0.068 mm. in length. Smaller pair of hooks approximately one half the size of larger hooks, situated between and posterior to larger anterior pair. Mouth subterminal, ventral. Two anterior mouth suckers elliptical, longer than broad, 0.056 mm. in length by 0.04 mm. in width. Small pharynx just posterior to anterior suckers. Esophagus short, bifurcating anterior to genital pore. Intestinal limbs with lateral branches, not united behind. Cirrus consists of cup- shaped body with two bean-shaped bodies attached to it posteriorly. Diameter of cirrus cup 0.068 mm. Bean-shaped bodies 0.072 mm. in length. Spines of bean-shaped body straight, sharp, pointed toward mid-line and obliquely downward, 0.012 mm. in length. Testes small, slightly lobed, in mid-line in anterior part of posterior half of animal, twenty-six in number, length of testicular region 0.848 mm., width 0.271 mm. Vas deferens leaves base of penis cup passing posteriorly dorsal and to right of uterus. From genital pore to halfway to ovary it is slender without coils. It then broadens to over twice its anterior width and passes posteriorly by tortuous windings. Genital pore in mid-line, ventral, near posterior end just 48 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 posterior to bifurcation of esophagus to form intestinal limbs. Ovary in mid-line at posterior part of anterior third of animal, slender in diameter, U-shaped with open end of U pointing posteriorly. Start- ing on the left side the ovary passes forward and winds back and forth laterally about ten times and then turns to the right and passes horizontally across the mid-line and turns abruptly posteriorly and winds horizontally about six times. Oviduct arises from ovary at posterior end of right arm. Vitelline glands from slightly posterior to genital pore to anterior part of posterior third of testicular region, separated anteriorly and posteriorly but confluent between ovary and anterior part of testicular region. Uterus relatively wide and straight. Eggs with anterior and posterior filaments, 0.168 to 0.203 mm. in length by 0.072 to 0.080 mm. in width. Anterior and pos- terior polar filaments approximately 0.10 mm. in length. Comparisons. H. euthynni is considerably different from any previously described species. It varies particularly in the chitinous skeleton of the posterior suckers. Each sucker has three X-shaped bars parallel to the anterior-posterior axis of the body. The sucker is divided into two portions with a long bar separating the two sides and a short one imbedded in the lateral wall of the sucker on each side. Since this description was made from only one specimen the species is provisional. The species name is derived from the genus name of the host, Euthynnus alletteratus (Rafinesque). Famity: MAZOCRAEIDAE Price, 1936 Mazocraes macracanthum, new species (Plate 6, figs. 25-29) Host: Unidentified species of mackerel Location: Gills Locality: Tagus Cove, Albemarle Island, Galapagos Is- lands Number: 8 Body elongated, lanceolate, tapering anteriorly, slightly broader posteriorly, 1.473 to 2.340 mm. in length by 0.356 to 0.474 mm. in width. Posterior haptor relatively large, separated from rest of body by slight constriction, with eight posterior suckers arranged in two No. 5 MESERVE: MONOGENETIC TREMATODES 49 parallel rows. Posterior suckers elliptical, wider than long, anterior pair smaller, 0.048 to 0.060 mm. in length by 0.060 to 0.068 mm. in width; other three pairs 0.056 to 0.068 mm. in length by 0.068 to 0.080 mm. in width. Chitinous skeleton (fig. 27) of four pieces, central piece heavy, very broad, bifurcated and blunt posteriorly, bifurcated anteriorly with two sharp points which are recurved, sharply pointed, pointing toward base of sucker; two pairs of lateral pieces, heavy, uniting posteriorly; an anterior piece horizontally across top of sucker with ends bent slightly and pointing toward base of sucker. Two pairs of hooks at posterior end of body between posterior pair of suckers. Outer pair extremely large and stout, 0.100 to 0.132 mm. in length, solid with sharp, recurved points, opposite ends (anterior roots) truncate, anterior root one third distance from distal end; proximal half of hook deeply grooved on its surface. Inner pair hooks approximately one sixth length of larger pair, 0.02 mm. in length, filiform, with sharp recurved points, possessing a process about one third the distance from the distal end, posterior end of hook slightly turned up at end. Each sucker with skeletal apparatus of four pieces. Mouth subterminal, ventral. Anterior mouth suckers large, elliptical, broader than long, without mem- branous septa. Pharynx bulb-shaped, near anterior suckers, slightly longer than wide. Esophagus relatively long, slender, bifurcating approximately one half distance from anterior end of animal to ovary. Intestinal limbs extend posteriorly to anterior end of posterior pair of suckers, not united posteriorly, with lateral branches. Cirrus consists of central bulb-shaped body 0.052 to 0.064 mm. in diameter. Two lateral bean-shaped bodies of cirrus longer than wide, 0.048 mm. in length. Five pairs of cirrus hooks, one pair of stout, long hooks with broad bifurcated bases and sharp slightly curved points, and four pairs of smaller inner hooks which have bulb-shaped bases and taper gradually from the proximal to distal ends and are slightly curved from base to point. Testes large, few in number (ten), smooth, unlobed, broader than long and angular, to right of and posterior to ovary in anterior part of posterior half of animal. Genital pore in mid-line near anterior end, about one half the distance from anterior end of animal to bifurcation of esophagus. Ovary in middle of body to left of mid-line, U-shaped with open end of U pointing anteriorly, both arms approximately the same length and of uniform diameter throughout. Oviduct leaves anterior part of right arm of 50 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 ovary and bends obliquely posterior toward mid-line. Vitellaria rela- tively fine, acinous, from halfway between genital pore and bifurca- tion of esophagus to level of anterior pair of posterior suckers. Vitelline ducts unite in mid-line anterior to ovary. Common yolk duct very large with diameter as great as diameter of ovary. No eggs present. Comparisons. M. macracanthum is most similar to Octocotyle minor Goto, 1894. The length of the posterior suckers in O. minor is 0.03 mm. as compared with 0.056 to 0.064 mm.; there are six pairs of cirrus hooks as compared with five; and the large pair of posterior hooks measures 0.037 mm. in length as compared with 0.100 to 0.123 mm. M. macracanthum gets its name from the fact that the posterior hooks are extremely large. Famity: MICROCOTYLIDAE Tacuenszere, 1879 Genus: MicrocoryLe vAN Ben. and Hesse, 1863 The genus Microcotyle is a very large one. At least fifty-eight species have been named. For reference purposes these species are listed alphabetically with their hosts. 1. M. acanthophallus MacCal. and MacCal., 1913 on Roccus lineatus. 2. M. acanthurum Par. and Per., 1890 on Brama ray. 3. M. alcedinis Par. and Per., 1890 on Smaris alcedo, Maena trachim and M. vulgaris. 4. M. angelichthys MacCal., 1913 on Holocanthus ciliaris. . M. angelichthys-townsendi MacCal., 1916 on Angelichthys townsendi. (Note: In the description this is written with- out the hyphen as M. angelichthys townsendi. The hyphen is being inserted here so that the name will be binomial and comply with the rules of nomenclature. Without doubt, Mac- Callum did not mean to create a subspecies.) . M. archosargi MacCal., 1913 on Archosargus probatocephalus. . M. australiensis MacCal., 1921 on Pomatomus saltatrix. . M. australis Murray, 1931 on Sparus australis. . M. bassensis Murray, 1931 on Platycephalus bassensis. . M. branchiostegi Yamaguti, 1937 on Branchiostegus japonicus. wal oO 00 SJ ON — jos) No. 5 SEERES SSS EESEES555E555555 MESERVE: MONOGENETIC TREMATODES St M. canthari van Ben. and Hesse, 1863 on Cantharus grisseus, C. lineatus, and C. brama. . carangis MacCal., 1913 on Caranx crysos. . caudata Goto, 1894 on Sebastes sp. . centrodonti Brown, 1929 on Pagellus centrodontus. centropristes MacCal., 1913 on Centropristes striatus. . cepolae Yamaguti, 1937 on Cepola schlegeli. . chirt Goto, 1894 on Chirus hexagrammus. . M. chrysophryi van Ben. and Hesse on Chrysophryi vul- garts. . M. donovani van Ben. and Hesse, 1863 on Labrus donovani. . M. draconis Briot, 1904 on Trachinus draco. . M. elegans Goto, 1894 on Scombrops chilodipteroides. . M. eriensis Bangham and Hunter, 1936 on Aplodinotus grun- niens. . M., erythrini van Ben. and Hesse, 1863 on Pagellus erythrinus P. acarne and Box boops. . eueides MacCal. and MacCal., 1913 on Roccus lineatus. fusiformis Goto, 1894 on Centronotus rubulosus. gotot Yamaguti, 1934 on Hexagrammos otakii. hiatulae Goto, 1899 on Hiatula onitis. incisa Linton, 1910 on Neomaenia grisseus. incomparabilis MacCal., 1917 on Caranx ruber. labracis van Ben. and Hesse, 1863 on Labrax lupus. longicauda Goto, 1899 on Cynoscion regale. lichiae Ariola, 1899 on Lichia amia. macroura MacCal. and MacCal., 1913 on Roccus lineatus. mormyrt Lorenz, 1878 on Pagellus mormyrus. . mugilis Vogt, 1878 on Mugil cephalus. . pagrosomi Murray, 1931 on Pagrosomus auratus. . pancern Sonsino, 1891 on Umbrina cirrhosa. . pogoniae MacCal., 1913 on Pogonias cromis. . polynemi MacCal., 1917 on Polynemus auratus. . pomatomi Goto, 1899 on Pomatomus saltatrix. . M. pomocanthi MacCal., 1915 on Pomocanthus arcuatus, Chaetodon ocellatus, Calamus arctifrons, Anisotremus vir- ginicus, Ephinephelus flavolimbatus, and Harpe rufa. . M. poronoti MacCal., 1915 on Poronotus triacanthus. . M. pyragraphorus MacCal. and MacCal., 1913 on Trachi- notus carolinus. 52 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 44. M. reticulata Goto, 1894 on Stromateus argenteus. 45. M. salpae Par. and Per., 1890 on Box salpa. 46. M. sargi Par. and Per., 1890 on Sargus rondeletii, S. annularis, S. salviani, and S. vulgaris. 47. M. sciaenae Goto, 1894 on Sciaena sina. 48. M. sciaenicola Murray, 1932 on Sciaena antarctica. 49. M. sebastis Goto, 1894 on Sepastes sp., S. maliger, S. caur- inus, S. melanops, and Sebastodes schlegeli. 50. M. sillaginae Woolcock, 1936 on Sillaginoides punctatus. 51. M. sp. Linton, 1907 on Calamus calamus. 52. M. spart Yamaguti, 1937 on Sparus longispinus. 53. M. spinicirrus MacCal., 1918 on Aplodinotus grunniens. 54. M. stenotomi Goto, 1899 on Stenotomus chrysops. 55. M. trachini Par. and Per., 1899 on Trachinus radiatus. 56. M. truncata Goto, 1894 on Pristipoma japonicum. 57. M. victoriae Woolcock, 1936 on Helicolenus percoides. 58. M. virgatarum Tubangui, 1931 on Teuthis virgata. Microcotyle priacanthi, new species (Plate 6, figs. 30-32) Host: Priacanthus sp. Location: Gills Locality: Hood Island, Galapagos Islands Number: 4 Body long, slender, lanceolate, 2.980 to 4.333 mm. in length by 0.237 to 0.339 mm. in greatest width, tapering to a point at posterior end, anterior end attenuated and bluntly pointed. Posterior haptor long, approximately four fifths of total body length. Numerous (approximately 200) small posterior suckers 0.044 to 0.048 mm. in length by 0.060 to 0.064 mm. in width. Chitinous skeleton (fig. 32) of seven pieces, a central inverted U-shaped piece, one arm of U longer than the other and bifurcated at proximal end; two lateral pairs, relatively slender; one pair at distal end of lateral pairs ex- tending obliquely downward and toward center of sucker; one pair across top of sucker, somewhat beaded in appearance and convex on distal borders. Mouth subterminal, ventral. Pharynx almost spherical, 0.032 to 0.036 mm. in length by 0.032 to 0.040 mm. in width. Esophagus relatively short, bifurcating in front of genital pore. Intestinal limbs with lateral branches ending blindly. Anterior No. 5 MESERVE: MONOGENETIC TREMATODES 53 suckers elliptical, broader than long, with membranous septa, 0.032 to 0.036 mm. in length by 0.060 to 0.064 mm. in width. Genital pore near anterior end, halfway from anterior end to vitellaria. Genital atrium (fig. 31) armed with two sets of hooks; sixteen in anterior set forming an incomplete circle, open posteriorly. Anterior genital hooks long, slender, 0.024 to 0.028 mm. in length. Twelve posterior hooks consisting of four strong chitinous spines with slightly recurved points on each side and four other hooks posterior and median pointing anteriorly and associated with a strong, mus- cular sucker-like structure. The paired posterior spines 0.020 to 0.032 mm. in length. Testes large, smooth, almost spherical, eleven in a single row posterior to ovary and extending almost to haptor. Ovary in middle of body in mid-line, shaped like a question mark from ventral side, right arm broader and about one half as long as left arm. Oviduct arises from lower part of right arm. Seminal recep- tacle spherical, posterior to lower end of right arm. Vagina single, straight, dorsal, median, opening dorsally posterior to level of an- terior end of vitellaria. Vitellaria from just anterior to vaginal open- ing to short distance into haptor. No eggs present. Comparisons. M. priacanthi has eleven testes as compared to M. erythrini (which has ten) but differs in number, size, and ar- rangement of the genital spines and the posterior suckers. M. sargi has an incomplete corona of sixteen hooks in the genital atrium as compared to twenty-eight. M. momyri has 120 to 130 posterior suckers as compared with almost 200; its spines in the genital atrium differ greatly in number, size, and arrangement. M. chiri has a simi- lar cup-shaped organ in the genital atrium but has only sixty suckers and twenty-five testes as compared to 200 and eleven. M. sciaenae differs in number, size, and arrangement of the genital spines and the number and size of the posterior suckers. M. priacanthi is named after the genus name of the host, Pria- canthus. Gotocotyla acanthocybii, new species (Plate 6, figs. 33-36) Host: Acanthocybium solandri (Cuv. and Val.) Location: Gills Locality: Galapagos Islands Number: 15 54 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 Body elongated, leaf-like, tapering at anterior end and rounded at posterior end, 6.283 to 11.093 mm. in length by 0.848 to 0.953 mm. in greatest width just anterior to haptor. Posterior haptor long, over one half total body length, 0.953 to 1.256 mm. in width at widest part, with two hooks at posterior end. These hooks measure 0.024 to 0.056 mm. in length and have sharp recurved points. Posterior suckers 223 to 245 in number arranged along each side of haptor, elliptical, broader than long, 0.072 to 0.076 mm. in length by 0.076 to 0.080 mm. in width. Chitinous skeleton of each sucker (fig. 35) consists of fifteen pieces; one median, large; two elongated, curved, in each side; two short curved pieces in base of sucker; and four pairs straight, slender, chitinous rods imbedded in wall on each side, equidistant from each other and in posterior half of sucker. Mouth ventral, sub-terminal. Pharynx bulb-shaped, slightly longer than broad, 0.056 to 0.064 mm. in length by 0.040 to 0.056 mm. in width. Esophagus relatively large in diameter with several lateral branches on each side, bifurcating just in front of genital pore. In- testinal limbs with lateral branches, uniting near posterior end. An- terior suckers elliptical, longer than broad, without membranous septa, 0.080 to 0.108 mm. in length by 0.044 to 0.048 mm. in width. Genital pore well forward about one third distance from anterior end to vitellaria. Genital atrium a large, globular cavity heavily armed with numerous (several hundred) spines 0.020 to 0.048 mm. in length, elliptical, twice as wide as long (fig. 33). Vas deferens dorsal to the uterus, opening at the flattened tip of an irregular glob- ular-shaped papilla which projects into cavity of genital atrium. This papilla may be the homologue of the cirrus of other forms. It appears to be muscular. Testes fifty-three to eighty-five in number, relatively small, irregular, smooth, posterior to ovary. Ovary situated at about middle of body in mid-line forming an inverted U, right arm shorter and of greater diameter than left arm, left arm with distinct en- largement at posterior end. Oviduct arises from lower end of right arm. Vitellaria relatively fine, acinous, extending from posterior part of anterior fifth of body to posterior end of animal, confluent be- hind, separated in front. Yolk ducts unite in mid-line at level of posterior third of ovary. Common yolk duct relatively short and slender. Eggs elliptical, over twice as long as wide, 0.140 to 0.208 mm. in length by 0.052 to 0.084 mm. in width, long polar filament at each end. Eggs vary in number from several to forty-seven. Ex- cretory pores open dorsally almost at extreme lateral edge of animal. No. 5 MESERVE: MONOGENETIC TREMATODES 55 Comparisons. G. acanthocybii has 223 to 245 posterior suckers as compared to 120 in G. acanthurum (Par. and Per., 1890) and thirty-seven in G. carangis (MacCal., 1913). It also differs in size, number, and arrangement of genital spines and posterior suckers from G. acanthurum and G. carangis. G. acanthocybu is named after the genus of its host, Acantho- cybium. The genus Gotocotyla was named by Ishii in 1936, but at the present writing his paper is not available to the writer. The genus is apparently like Microcotyle, but with a pair of hooks at the pos- terior end of the body. Gotocotyla elagatis, new species (Plate 7, figs. 37-40) Host: Elagatis bipinnulatus (Quoy and Gaimard) Location: Gills Locality: Bahia Honda, Panama Number: 4 Body lanceolate, bluntly pointed at anterior end, pointed at pos- terior end, 3.263 to 6.200 mm. in length by 0.550 to 0.661 mm. in greatest width. Posterior haptor approximately one fourth entire body length, not distinctly marked off from rest of body proper, with ninety to 100 suckers. Posterior suckers slightly longer than broad, 0.044 to 0.060 mm. in length by 0.036 to 0.044 mm. in width. Chitinous skeleton of each sucker (fig. 39) complex, con- sisting of twenty-two pieces, two strong curved pieces on one side in lateral wall of sucker and two slender curved pieces on opposite side; one wide short piece on side bearing the two strong pieces, in base and extending obliquely outward almost one half the length of sucker; at base on other side one strong piece bent toward base of sucker at middle; eight to ten slender inverted U-shaped pieces, equidistant apart in outer half of sucker on the side bearing the two slender upright curved rods; six small pieces scattered through- out lower half of sucker. Two hooks at posterior end, 0.40 to 0.48 mm. in length, with strongly recurved points bending to right and left away from each other with their points directed outward. An- terior suckers elliptical, longer than broad, 0.060 to 0.076 mm. in length by 0.032 to 0.044 mm. in width, with membranous septa. Pharynx bulb-shaped, 0.020 to 0.060 mm. in length by 0.018 to 56 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 0.032 mm. in width. Esophagus slender, bifurcating in region of genital pore. Intestinal limbs extending to half length of haptor, with lateral branches not uniting posteriorly. Genital pore 0.180 to 0.271 mm. from anterior end. Genital atrium with numerous straight chitinous rods, 0.016 to 0.200 mm. in length, arranged in a circle. Testes small, numerous (several hundred), smooth, elliptical, closely packed in posterior third of body between ovary and haptor. Ovary in middle of body in mid-line, shape of inverted U, long and slender with arms of approximately the same length, left arm slightly longer. Oviduct arises from right arm. Vitellaria fine, acinous, from anterior ith to middle of testicular region. Vitelline ducts unite at level of posterior third of ovary. Uterus relatively straight and broad in mid-line. No eggs present. Comparisons. G. elagatis has ninety to 100 posterior suckers compared with 120 in G. acanthurum and thirty-seven in G. caran- gis, one group of genital spines compared with two groups. G. acanthocybu has one group of genital spines but they differ in num- ber, size, and arrangement; fewer testes (fifty-two to eighty-four testes compared with several hundred in G. elegatis and sixty in G. carangis), and the vitellaria extend only to haptor rather than to middle of haptor region. G. elagatis is named after the genus name of the host, Elagatis. Genus: ‘'THorAcocotyLeE MacCa.ium, 1913 MacCallum (1913) described Thoracocotyle from the Spanish mackerel (Scomberomorus maculatus). It is unique among the Monogenea in that most of the body functions as a haptor. Most of the body proper lies flat on the substratum or attached to the host by suckers along each side while the rest and least conspicuous part of the animal arises dorsally and at right angles to the haptor region, The anterior part of the animal is practically free from organs with the exception of the almost straight uterus and the relatively broad tortuous vas deferens which lies dorsal to the uterus. Ap- parently due to the fact that the anterior part of the animal is free from organs, the vas deferens swings broadly from side to side and occupies about one half the width of this part of the animal. Price (1936) places this genus in the Diclidophoridae instead of the Microcotylidae and created a new subfamily, Thoracocotylinae. No. 5 MESERVE: MONOGENETIC TREMATODES 57 Thoracocotyle paradoxica, new species (Plate 7, figs. 41-43) Host: Scomberomorus maculatus (Mitchill) Location: Gills Locality: Tangola~Tangola, Mexico Number: 1 Posterior region of body which functions as a haptor 1.476 mm. in length by 0.508 in greatest width. The anterior part of the body is attached to the anterior part of the haptor region, 0.712 by 0.288 mm. in greatest width. The haptor extends 0.968 mm. to the left and 0.508 mm. to the right of the anterior part of the body. Posterior suckers along margins of haptor, eight pairs on posterior part of haptor and six pairs on anterior part. The three pairs on anterior part considerably smaller, as is the sucker at the extreme tip at anterior end of haptor; each one of large suckers, 0.080 mm. in length by 0.100 in width, slightly broader than long. Chitinous framework (fig. 43) typical of the genus with six to ten slender curved pieces imbedded in walls in each side of sucker, one heavy, central I-shaped piece, two lateral curved pieces and one pair on each side at distal end of sucker, curved downward. Two pairs of hooks at posterior tip of haptor, outer pair longer, slender, rela- tively straight with short recurved points and process at middle, 0.048 mm. in length; inner pair posterior, arcuate and, in shape, resembling a small hand scythe with short handle, 0.016 mm. in length. Slightly anterior to hooks are six conspicuous nuclei, deeply staining with heavy nuclear membranes and prominent eccentric nucleoli. Mouth ventral, slightly subterminal. Anterior mouth suck- ers elliptical, without septa, broader than long, 0.024 mm. in length to 0.044 mm. in width. Pharynx muscular, bulb-shaped, 0.052 mm. in length by 0.035 mm. in width. Rest of digestive system not visible. Genital pore just posterior to pharynx in mid-line, unarmed. Testes seven in number, smooth, unlobed, longer than wide, in mid-line posterior to ovary, close together and in one row. Vas deferens a broad tortuous tube in mid-line. Cirrus rudimentary, unarmed. Ovary shaped like inverted U in mid-line between seventh pair of suckers counting from posterior end. Shell gland large, spherical, posterior to ovary. Vitellaria in two groups, one in anterior part of haptor and one in posterior part, confluent anteriorly and posteriorly. 58 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 Egg 0.168 mm. in length by 0.064 mm. in width with one polar fila- ment 0.292 mm. in length. Comparisons. There is some doubt that the species described in this paper differs from MacCallum’s. The main point of differ- ence seems to be the number of posterior suckers of the haptor, which number forty in 7. croceus and only twenty-eight in T. para- doxica. However, since only one specimen and the anterior part of another were studied and MacCallum had only a few of his species, the variation is not well known. For this reason T. paradoxica is proposed as a provisional species. T. paradoxica is named for the fact that it appears most peculiar in that most of the body proper functions as a haptor. Genus: AxineE ABILDGAARD, 1794 The following species of Axine have been described to date: . aberrans Goto, 1894 on Belone schismatorhynchus. . belones Abild., 1794 on Belone acus. . carangis MacCal., 1918 on Caranx hippos. . heterocerca Goto, 1894 on Seriola quinqueradiata. . triangularis Goto, 1894 on Anthias schlegeliu. RA A A A Axine oligoplitis, new species (Plate 8, figs. 44-47) Host: Oligoplites saurus (Bloch and Schneider) Location: Gills Locality: San Francisco, Ecuador Number: 4 Body small, triangular, 1.820 to 1.950 mm. in length by 0.305 to 0.322 mm. in greatest width just anterior to ovary. Posterior haptor triangular with sixteen to eighteen suckers on short side and forty to forty-two on long side. Posterior suckers 0.024 to 0.036 mm. in length by 0.044 mm. in width. Chitinous framework (fig. 45) consists of two pairs of lateral pieces which are slender and widely open behind, a central median piece which is also slender and bifur- cated at both ends, and a slender pointed spine distal to lateral paired pieces imbedded in lateral wall. Mouth ventral and sub- terminal. Anterior suckers relatively far apart, elliptical, broader No. 5 MESERVE: MONOGENETIC TREMATODES 59 than long, without membranous septa, 0.024 to 0.036 mm. in length by 0.056 to 0.064 mm. in width. Pharynx bulb-shaped, 0.024 to 0.032 mm. in length by 0.022 to 0.029 mm. in width. Esophagus slender, bifurcating in region of genital pore. Intestinal limbs with lateral branches, not united behind. Genital pore well forward 0.120 to 0.169 mm. from anterior end. Genital hooks in two rows on each side, one row dorsal to the other, dorsal hooks shorter; long ventral hooks 0.016 to 0.020 mm. in length, almost straight, wider at proxi- mal end with recurved points pointing posteriorly into genital pore. Short hooks a little over one half length of long hooks. Twenty- eight to thirty-nine testes in two rows posterior to ovary, smooth, wider than long, unlobed. Ovary in shape of interrogation point, anterior part expanded and posterior part with small lobe which is bent to left, in middle of body in mid-line, greatest diameter 0.056 to 0.076 mm. Seminal receptacle elliptical, to right of ovary. Vitellaria from genital pore to one half distance from testes to posterior end. No eggs present. Brain with two projecting anterior lobes with short lateral projections on each side. Comparisons. The two main features which distinguish 4. oligoplitis from others previously described are the hooks of the genital pore which are arranged in two parallel groups on each side of the genital pore and the brain which has two small extra lobes arising anteriorly from the brain proper. These accessory anterior lobes have small lateral extensions which arise lateral and at right angles to them. It is most like 4. aberrans Goto but is somewhat smaller (1.8 to 1.9 as compared with 5.0 mm.). 4. aberrans has twenty-five suckers on one side and only one on the other as com- pared with sixteen to eighteen suckers on one side and forty to forty-two on the other in 4. oligoplitis. A. oligoplitis is named after the genus of the host, Oligoplites. Axine seriolae, new species (Plate 8, figs. 48-52) Host: Seriola dorsalis (Gill) Location: Gills Locality: Hood Island, Galapagos Islands Number: 4 Body elongated triangular, slightly curved to right with greatest width at level of ovary, tapering gradually to anterior end of vitel- 60 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 laria in front of which is a slight constriction, 5.113 to 7.540 mm. in length to 1.082 to 1.300 mm. in greatest width, with papilla-like tip at anterior end. Surface of body smooth except ventral side with several hundred close, simple, sharply recurved hooks located around genital pore and extending from brain to ovary and laterally to inner borders of intestinal limbs. Posterior haptor triangular, ap- proximately one third total body length with twenty-seven to twenty- nine suckers on short side and thirty-eight to forty on long side. Posterior suckers 0.080 to 0.092 mm. in length by 0.140 to 0.184 mm. in width. Chitinous framework (fig. 49) consists of five main pieces, two curved, relatively heavy pieces on each side, one central piece Y- shaped at each end, and a short stout piece distal to paired lateral pieces, convex distally and inner end pointing toward mid-line of sucker. Anterior suckers far apart, broader than long, without septa, 0.076 to 0.092 mm. in length by 0.120 to 0.168 mm. in width. Mouth small, subterminal, ventral. Pharynx bulb-shaped, longer than broad. Esophagus slender with few lateral branches bifurcating ap- proximately halfway between brain and genital pore at level of excretory pores. Intestinal limbs extending into haptor region, with lateral branches ununited. Genital pore in mid-line halfway from anterior end to vitellaria, unarmed except for the spines mentioned above. Testes posterior to ovary to anterior end of short side of haptor, ninety-three to 105 in number, close together, oval, unlobed. Ovary in mid-line just in front of testes extending anteriorly from oviduct region on right side winding horizontally six times, then turning abruptly to left at right angles to right arm and after pass- ing horizontally to left, again turning abruptly posteriorly, it then bends and passes obliquely anterior and to right and after reaching uterus passes dorsal to it and again bends obliquely posterior and te right with slight enlargement at lower end of left arm. Vaginal opening in mid-line on dorsal surface, unarmed, halfway from con- striction at anterior fourth of body to anterior border of vitellaria, opening into two ducts which extend to right and left in horizontal plane expanding laterally and bending posteriorly about midway to lateral borders of animal. It was not possible to follow them pos- teriorly. Vitellaria in two distinct groups from constriction at level of anterior fourth of animal to posterior border of testicular region, one third of width of animal in mid-line free from them for entire length. Yolk ducts unite to form common duct at middle of vitellaria No. 5 MESERVE: MONOGENETIC TREMATODES 6l in mid-line. Eggs elongated oval, 0.096 to 0.136 mm. in length to 0.056 to 0.068 mm. in width, with extremely slender filiform polar filament at one end of egg approximately one and one-half times the length of egg. Comparisons. A. seriolae is most similar to 4. heterocerca Goto, 1894, but is smaller (5.1 mm. to 7.5 mm. in length compared with 10.0 mm.), with twenty-seven to twenty-nine suckers on one side of the haptor and thirty-eight to forty on the other as compared with nine on one side and thirty on the other. The vitellaria are sepa- rated along the entire length of the body as compared with the posteriorly confluent vitellaria of 4. heterocerca. A. seriolae is named after the genus of its host, Seriola. Axine elongata, new species (Plate 8, figs. 53-58) Host: Xurel malampygus (Cuv. and Val.) Location: Gills Locality: Secas Island, Panama Number: 5 Body long, slender, tapering slightly from posterior haptor to anterior end which has a pronounced papilla-like structure at tip, body 2.080 to 3.683 mm. in length by 0.288 to 0.531 mm. in greatest width. Posterior haptor asymmetrical, 0.848 to 0.932 mm. in length by 0.508 to 0.593 mm. in width, four to five suckers on short side, twenty-four to twenty-five on long side. Posterior suckers slightly longer than broad, 0.060 to 0.080 mm. in length by 0.048 to 0.080 in width. Chitinous skeleton (fig. 57) consists of a broad central piece split down the center on one side with broadly bifurcating ends, one side shorter than other; two pairs of lateral pieces uniting at bases, one enlarged piece, blunt and slightly bifurcated at distal end, other piece attenuated; a strong spine-like piece at base on each side. Anterior sucker relatively small, wide apart, wider than long; without membranous septa, 0.040 to 0.044 mm. in length by 0.036 to 0.060 mm. in width. Mouth ventral and subterminal. Pharynx elongated, bulb-shaped, 0.040 to 0.044 mm. by 0.026 to 0.040 mm. in width. Intestinal limbs long, slender with lateral branches, extend well into haptor region, left branch shorter than right, ending blindly just in front of loop made by union of lateral 62 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 nerve cords. Genital pore located in mid-line, unarmed, well forward, 0.180 to 2.268 mm. from anterior end. Testes irregular, smooth, in posterior fourth of body posterior to ovary, twenty-seven to forty- eight in number. Ovary in anterior part of posterior third of body in shape of question mark, anterior end enlarged, posterior end bent back on itself for a short distance. Oviduct arises from anterior expanded portion of ovary. Uterus greatly expanded to one half body width, from genital pore to ovary, filled with many eggs. Eggs fusiform, pointed at both ends, four times as long as wide, 0.160 to 0.176 mm. in length by 0.040 to 0.044 mm. in width with opercu- lum at anterior end and slender polar filament at each end, not quite as long as egg. Nervous system with typical brain on dorsal side just in front of genital pore, lateral nerve cords very prominent with cross commissure connecting them at anterior part of haptor, con- nected at posterior end, with attenuated branch on right side anterior tc suckers at anterior end of long side of haptor and slender nerves arising from lateral nerve cords going to base of suckers. Comparisons. A. elongata differs from A. carangis MacCallum, 1918 in having an unarmed genital pore and in the number, size, and arrangement of the posterior suckers. 4. heterocerca Goto, 1894 has thirty suckers on one side of the haptor and nine on the other as compared to twenty-four to twenty-five and four to five, and also differs in body size and size of suckers as well as posteriorly confluent vitellaria. A. elongata is named from the fact that it is relatively long com- pared with its width. Axine aberrans Goto, 1894 (Plate 9, fig. 59) Host: Tylosurus fodiator (Jordan and Gilbert), aguj6n, or hound fish Location: Gills Locality: Port Utria, Colombia Number: 6 This species was described by Goto in 1894 from the gills of Belone schismatorhynchus. Those found in Colombia are smaller, measuring 1.7 to 2.3 mm. Goto’s measure 5.0 mm. in length. In other respects, however, these specimens agree with Goto’s de- scription. No. 5 MESERVE: MONOGENETIC TREMATODES 63 Pseudaxine mexicana, new species (Plate 9, figs. 60-63) Host: Scomberomorus maculatus (Mitchill) Location: Gills Locality: =Tangola-Tangola, Mexico Number: 2 Body relatively short and narrow curving to left, 1.950 mm. in length by 0.322 to 0.373 mm. in width at widest part at middle of body and tapering slightly anteriorly and posteriorly. Posterior hap- tor almost as wide as length of body proper, extremely convex at posterior end, bearing thirty-seven suckers. Posterior suckers large, elliptical, broader than long, 0.058 mm. in length by 0.088 mm. in width. Chitinous skeleton (fig. 61) of suckers has broad triangular piece at anterior of central piece which has two lateral hook-like prolongations at distal end; middle part of central piece double with wide elliptical opening between the two sides, joining at posterior te form another triangular piece which is not quite as wide as an- terior one; two pairs of relatively slender curved pieces at sides, one pair somewhat longer than the other and after enlarging at distal tips tapering to fine points; one pair imbedded in base of sucker almost touching each other medianly, approximately one third width of sucker, wider at proximal end, extending obliquely anteriorly and laterally; six to seven slender, equidistant pieces im- bedded in each side of sucker. Mouth subterminal, ventral. Pharynx bulb-shaped, 0.044 to 0.056 mm. in length by 0.028 mm. in width. Esophagus relatively short and slender, bifurcating in region of genital pore. Intestinal limbs with lateral branches, not united be- hind. Genital pore well forward one half distance from anterior end to anterior border of vitellaria. Testes from posterior to ovary to haptor, relatively small, wider than long, irregularly arranged in two rows, thirty-six in number. Vas deferens a relatively wide tor- tuous tube winding horizontally twelve to fourteen times before reaching upper end of ovary where it is more slender and passes almost straight posteriorly in mid-line to testes, enlarged at anterior end to form cirrus. Cirrus armed with ten straight, slender pointed spines pointing anteriorly, arranged around top of cirrus in a circle and slanting inward toward each other at the anterior end; 0.018 mm. in length. Ovary slightly posterior to middle of body on left 64 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 side halfway from mid-line to lateral edge of body, inverted U- shaped, left arm somewhat shorter than right and more slender, posterior end of right arm bends on itself and after running anteri- orly a short distance it bends back on itself and passes posteriorly for a short distance. Oviduct arises from lower end of right arm. No eggs present. Comparisons. P. mexicana is very similar to P. trachuri Par. and Per., 1890. The chief differences seem to be the more anterior posi- tion of the genital pore which is near the pharynx in P. mexicana but posterior to the intestinal bifurcation in P. trachuri; the apparent lack of the anterior crown of genital spines; the more coiled vas deferens and biloculate rather than uniloculate buccal suckers. The vitellaria in P. trachuri extend forward to the genital pore and are a considerable distance posterior to it in P. mexicana. P. trachuri measures 4.0 to 6.0 mm. in length as compared to 1.95 in P. mexi- cana which has, however, larger buccal suckers, larger suckers on the haptor, and larger posterior hooks. The thirty-seven claspers on the haptor are not significantly different from twenty-four to thirty- two found in P. trachuri. P. mexicana is named after its geographic location, Mexico. Protomicrocotyle pacifica, new species (Plate 9, figs. 64-74) Host: Xwurel marginatus (Hill) Location: Gills Locality: Port Culebra, Costa Rica Number: 11 Body elongate, flat, broadest at anterior third, attenuated an- teriorly, and tapering posteriorly to the haptor, 2.8 to 4.33 mm. in length, width at anterior third 0.996 to 1.430 mm. Posterior haptor dumbbell-shaped bearing three pairs of hooks, outer hooks larger and more anteriorly located, with sharp recurved points directed an- teriorly and bifurcated enlargement at middle of length, 0.040 mm. in length; second pair short, slightly anterior to inner pair, 0.016 mm. in length; inner hooks similar in shape to outer, 0.024 mm. in length. Four posterior suckers on left side at posterior end, ventral, elliptical, broader than long, 0.076 to 0.092 mm. in length by 0.108 to 0.120 mm. in width. Chitinous skeleton (fig. 65) consists of cen- No. 5 MESERVE: MONOGENETIC TREMATODES 65 tral piece slightly broader at base bifurcating at distal end; one pair of lateral pieces connected posteriorly with blunt tip at distal ends and a pair of projecting pieces, stout and bluntly pointed, pointing halfway to base of sucker and obliquely toward central piece; one pair of lateral pieces separated posteriorly, not as long as other pair. Brain anterior to pharynx. No eyes. Excretory pores paired, dorsal, lateral almost to the edge of worm. Mouth sub- terminal, ventral. Two anterior suckers elliptical, without mem- branous septa, broader than long, 0.044 to 0.054 mm. in length, 0.060 to 0.092 mm. in width. Pharynx longer than wide, bulb-shaped, 0.100 to 0.116 mm. in length by 0.080 mm. in width. Esophagus long, branched, in mid-line to right of genital atrium and to left of vaginal opening, bifurcating short distance posterior to genital open- ing. Intestinal crura extend to haptor, separated posteriorly, numer- ous lateral branches to outside, few to inside. Genital pore ventral, to left of mid-line. Genital atrium elliptical, large, longer than broad, with ten short hooks and ten long hooks with sharp recurved points, short hooks 0.108 to 0.120 mm. in length, long hooks 0.168 to 0.184 mm. in length. Ovary in posterior part of body. Genitointestinal canal present. Vitellaria, fine, acinous, extend from genital atrium to haptor, separated in front and intermingled behind. Uterus opens into side of genital atrium. Vaginal opening ventral, to right of mid- line, armed with numerous, short, triangular spines, 0.008 to 0.012 mm. in length. Vagina simple. Testes anterior to ovary, small and numerous (150 to 200). Vas deferens opens into base of genital atrium. Cirrus muscular, unarmed, cylindrical, in genital atrium. Eggs 0.046 mm. in width by 0.160 mm. in length with polar fila- ment at each end. Comparisons. P. mirabile (MacCallum) from Caranx hippos differs from P. pacifica in the length of the genital atrium spines, measuring 0.040 mm. in length and all approximately the same length, compared to spines of P. pacifica of two sizes, three to four times the length of spines of P. mirabile. The eggs of P. pacifica are 0.046 mm. in width by 0.160 mm. in length compared to 0.320 to 0.720 mm. by 0.080 to 0.140 mm. Discussion. This is another example of related species living on related hosts among the ectoparasitic trematodes, The type species, Protomicrocotyle mirabile (MacCallum, 1918), was found on Caranx hippos Linnaeus from the New York Aquarium. The above species, 66 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 P. pacifica, was found on the gills of Xurel marginatus (Gill) [syno- nym: Caranx marginatus (Gill)], from Port Culebra, Costa Rica. P. pacifica is named after its geographic location, the Pacific Ocean. The only other described species lives in the Atlantic Ocean. MacCallum (1918) described Acanthodiscus mirabile from Car- anx hippos, and placed it in the Gyrodactylidae van Ben. and Hesse. Johnston and Tiegs (1922) gave it the genus name Protomicrocotyle since Acanthodiscus was preoccupied and created the new subfamily Protomicrocotylinae. Poche (1925) placed it in a new family, the Protomicrocotylidae. The writer has examined and measured the type and paratypes which were sent to him by Dr. E. W. Price from the United States National Museum. Not only did MacCallum misinterpret structures but he also made mistakes in his measurements. The evidence from the type material indicates that when MacCallum says fifteen mi- crons he means 150 microns. He misinterprets the spines of the geni- tal atrium and calls them the penis spines. He does not mention the vagina. Price (1936), after re-examining the type material, reduces the family Protomicrocotylidae to subfamily rank since it does not differ enough from other microcotylids to warrant a new family. Cestracolpa cypseluri, new genus, new species (Plate 10, figs. 75-80) Host: Cypselurus callopterus (Gunther) Location: Gills Locality: Charles Island, Galapagos Islands Number: 2 Body 3.046 to 3.076 mm. in length by 0.678 to 0.695 mm. at greatest width, slender, broadest throughout middle third, tapering slightly anteriorly and posteriorly to middle of posterior third of body where it broadens posteriorly to haptor. Posterior haptor 1.018 to 1.300 mm. in width, broader than greatest body width, posterior border truncate with almost a straight edge bearing forty-one suck- ers in one row. Posterior suckers elliptical, four times as wide as long, 0.020 mm. in length by 0.080 mm. in width, located at equal distances one behind the other pointing diagonally anteriorly and toward the right with transverse axis at an approximate angle of forty-five degrees with long axis of body. Chitinous skeleton of | | No. 5 MESERVE: MONOGENETIC TREMATODES 67 suckers (fig. 76) composed of eleven pieces, central piece bifurcated at distal end, relatively short, bluntly bifurcated at proximal end; short piece placed horizontally distal to central piece and between its bifurcation, concave distally; four pairs in lateral walls of suckers, on each side a basal piece extending laterally from middle piece, convex at posterior border, and three curved, attenuated pieces pointing obliquely and distally toward mid-line of sucker, joining basal pair of lateral pieces at distal end; slender bar across top with beaded appearance, bending inward at center toward middle piece and convex at anterior borders on both sides. Anterior suckers ellip- tical, longer than broad, 0.068 to 0.072 mm. in length by 0.044 to 0.048 mm. in width, without membranous septa. Mouth subterminal, ventral, close to anterior end. Pharynx bulb-shaped, longer than wide, 0.044 to 0.056 mm. in length by 0.036 to 0.040 mm. in width. Esophagus extremely long and slender, passing ventral to brain swinging to left past genital pore and swinging back again to mid- line just posterior to genital pore, bifurcating posterior to genital pore slightly anterior to level of vaginal opening. Intestinal limbs slender with lateral branches, extend to haptor, not united posteri- orly. Brain as in Axine, a relatively great distance posterior to pharynx almost half distance from anterior end to genital pore. Testes large, smooth, broader than long, unlobed, sixty-two in num- ber, extending from ovary almost to haptor. Vas deferens relatively wide and winding, passing posteriorly to right of uterus. Cirrus at base of genital atrium, strongly muscular, cup-shaped, broader than long with open end of cup pointing anteriorly, upper rim has circle of fourteen strong curved spines, with points directed posteriorly and toward center of cup, 0.014 to 0.020 mm. in length. Genital pore anterior to bifurcation of esophagus. Genital atrium (fig. 78) with four groups of spines, a complete circle near the genital pore, with sharp recurved points directed away from center of circle, 0.016 mm. in length; two pairs of ten spines each on each side of circle around genital pore, 0.020 to 0.024 mm. in length, bending posteriorly from their base and then bending slightly anteriorly with sharp points forming two parallel rows on each side of the genital atrium; a posterior group attached to cirrus described above. Vagina opens dorsally on right side at extreme right edge of worm slightly posterior to level of bifurcation of esophagus. Vaginal spine (fig. 77) imbedded in wall of vagina at distal end extending out of vagi- 68 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 nal opening a short distance, 0.048 mm. in length by 0.018 to 0.020 mm. in diameter at base, with broad spherical base and tapering distally to outer distal tip which is bifurcated. Vaginal canal, single, slender, extending from vaginal opening obliquely posterior to the left and joining left vitelline duct. Ovary U-shaped, right arm almost twice as long as left arm, just anterior to middle of body in mid- line. Oviduct arises from right arm of ovary, is joined by common yolk duct near ovary, passes anteriorly to right of mid-line where it receives openings of seminal receptacle and genitointestinal be- fore joining upper end of common yolk duct on right side. Seminal receptacle elliptical, relatively large, twice as long as wide, to right of mid-line anterior to ovary, 0.108 to 1.120 mm. in length by 0.520 to 0.060 mm. in width. Vitellaria from vaginal canal on right side and level of bifurcation of esophagus on left to haptor, separated anteriorly and posteriorly. Common yolk duct elongated, sac-like, to left of mid-line. Genitointestinal canal present. Mature eggs not present. Large cells on each side of genital pore for which the author proposes the name giant cells (fig. 75), three pairs extending from brain to bifurcation of esophagus, from one fourth to one third width of animal at level of genital pore. C. cypseluri is named after the genus of its host, Cypselurus. GENERIC DIAGNOSIS OF CESTRACOLPA Body elongated, slender anteriorly, truncate posteriorly, asym- metrical due to unusual development of one side of posterior haptor. Long side of diagonal posterior haptor bears numerous (sixty to 100) suckers in a single row. No chitinous hooks at posterior end of body. Vaginal opening single, lateral. Vaginal canal single, bearing conspicuous spine at distal end. Genital spines in four groups, one anterior, one posterior, and two lateral. Testes numerous posterior to ovary. Mouth subterminal, ventral. Mouth cavity with a pair of elliptical suckers. Three pairs of giant cells on each side of genital pore. The giant cells on each side of the genital pore seem to be unique. The common yolk duct is enlarged, sac-like, and extends posteriorly to left of mid-line but instead of joining the oviduct at the posterior end it joins it at the anterior end. The vagina arises from the yolk duct on the right side just before the two yolk ducts unite. The four groups of genital spines, three groups associated No. 5 MESERVE: MONOGENETIC TREMATODES 69 with the atrium and one with the cirrus, are characteristic of the genus. Discussion. The shape, size, and arrangement of posterior suck- ers of Cestracolpa is similar to Axine. The genus differs from Axine principally in that it has a lateral vaginal opening with a conspicuous spine imbedded in the wall at distal end of vaginal canal and pro- truding from the vaginal orifice. The name Cestracolpa is from cestra, dart, and colpa, vagina, referring to the spine in the vagina. Cestracolpa yamagutii, new species (Plate 10, figs. 81-85) Host: Unidentified flying fish Location: Gills Localities: Clarion Island, Mexico, and open sea off coast of Mexico Number: 2 Body 7.323 to 7.886 mm. in length by 1.732 to 1.733 mm. at greatest width, divided into three portions, a slender, attenuated part anterior to vaginal opening, a broad middle part which tapers slightly from middle of body to level slightly anterior to haptor and the short broad region bearing haptor. Posterior haptor with con- cave border on right side, 1.168 to 1.169 mm. in width. Posterior suckers small, seventy-five in number, four times as wide as long, 0.020 mm. in length by 0.080 mm. in width. Chitinous skeleton (fig. 84) of suckers consists of a very wide, short piece in center bifur- cated at both ends; two pairs of relatively short and slender pieces imbedded in lateral walls of sucker; twenty-four short, almost straight pieces imbedded in base of sucker, twelve on each side; and two pieces across top with convex borders directed distally. Mouth subterminal, ventral, almost at extreme end. Pharynx rela- tively small, bulb-shaped, 0.044 mm. in length by 0.036 to 0.044 mm. in width. Esophagus long, relatively wide, in mid-line, bifurcating just anterior to level of vaginal opening. Anterior suckers small, elliptical, longer than broad without membranous septa, 0.060 to 0.064 mm. in length by 0.032 mm. in width. Intestinal limbs with lateral branches, not united posteriorly. Testes large, smooth, broader than long, in two rows, fifty-two in number. Vas deferens slender, 70 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 slightly winding tube from genital pore to one half distance to ovary after which it broadens to wide tortuous tube to left of ovary. Cirrus armed with circle of ten short spines with broad bases and fine, sharp recurved points directed toward center of cirrus. Cirrus spines 0.006 mm. in length. Genital pore in anterior narrow region of body halfway from anterior end to vaginal opening. Genital atrium with four sets of spines, an incomplete circle of fourteen spines surround- ing anterior end of uterus, 0.016 mm. in length, pointing anteriorly, curved, with distal ends pointing away from center of incomplete circle; two groups of thirty spines each arranged in a curve on each side of genital atrium, 0.012 mm. in length, slightly curved with points directed anteriorly and outward away from center of genital atrium; fourth group attached to cirrus. Vaginal opening dorsal, posterior to bifurcation of esophagus. Vaginal spine imbedded in wall at distal end of vagina not extending through vaginal orifice, 0.040 to 0.046 mm. in length by 0.020 mm. in width, slightly bifur- cated at tip. Vaginal canal single, slender, passingly obliquely pos- terior to left from vaginal pore joining middle of left vitelline duct. Ovary U-shaped in anterior third of body in mid-line, right arm broader, anterior end of left arm somewhat lobed. Oviduct arises from right arm of ovary and proceeds anteriorly as in C. cypselurt. Seminal receptacle elliptical, longer than broad to right of mid-line anterior to ovary, 0.152 mm. in length by 0.067 mm. in width. Vitel- laria from vagina on right side and level of bifurcation of esophagus on left to haptor, separated anteriorly and posteriorly. Common yolk duct slender to left of mid-line. Genitointestinal present. Mature eggs not present. Comparisons. C. yamagutii differs from C. cypseluri in size, be- ing over twice as long and wide. The region anterior to the vaginal opening is narrower. The ovary is closer to the anterior end. The vaginal spine is slightly shorter and differs greatly in shape, the basal portion is elongated, elliptical rather than spherical. The geni- tal atrium has the same number of groups of spines but their size, number, and arrangement are different, the central group making an incomplete circle as compared with a complete circle. The pos- terior suckers are seventy-five in number compared to forty-one and vary greatly in number and arrangement of skeletal pieces. C. yamagutii is named in honor of Professor Yamaguti of Japan. No. 5 MESERVE: MONOGENETIC TREMATODES 71 SUMMARY AND CONCLUSIONS A study was made of twenty-two species of Monogenea collected from the gills of marine fish by Dr. H. W. Manter from the Gala- pagos Islands, the Pacific Coast of South America, Central America, and Mexico, including some adjacent islands. Twenty new species are described. All are placed in known gen- era with one exception. Two previously described species, Encotyl- labe pagrosomi MacCallum and Axine aberrans Goto, are reported from new localities. One new genus is proposed: Cestracolpa, which has a character- istic lateral vaginal opening and a spine imbedded in the wall of the distal end of the vagina. New species are described in the following genera: Benedenia, Entobdella, Heterobothrium, Diclidophora, Microcotyle, Gotocotyla, Thoracocotyle, Axine, Pseudaxine, Protomicrocotyle, and Cestracolpa. Previously undescribed structures surrounding the genital pore of Cestracolpa cypseluri and C. yamagutti are described and the name giant cells proposed for them. The name glands of Goto is proposed for posttesticular glands first described by Goto and called different names by various authors. They are considered of taxonomic significance. The fact that related species of ectoparasitic trematodes live on related hosts is pointed out. For example, two species of Cestra- colpa were collected, both from flying fish. The twenty-two species described in this paper were each found on only one specific host although over five hundred fish representing approximately one hun- dred species were examined. 72 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 LITERATURE CITED Benepen, P. J. van 1853. Espéce nouvelle du genre Onchocotyle, vivant sur les branchies du Soymnus glacialis. Bull. Acad. Roy. Soc. Belg., 20:59-68. Coun, L. 1916. Epibdella steingréveri n.sp. Zeit. wiss. Zool., 115:460-488. FuurMANN, Otro 1928. 1. Ordnung der Trematoda: Monogenea van Beneden in “Handbuch der Zoologie” of Kukenthal and Krumbach., 2:4-32. Ga.utEn, Louis 1937. Recherches sur quelques trématodes Mondgenéses nouveaux ou peu connus. Ann. Par., 15:9-28; 146-154. Goto, S. 1894. Studies on the ectoparasitic trematodes of Japan. Jour. Coll. Sc., Imp. Univ. Tokyo, 8:1-273. Guser ET, J. E. 1936. Two new ectoparasitic trematodes from the sting ray, Myliobatus cali- fornicus. Amer, Mid. Nat., 17:954-964. Heatu, Haroip 1902. The anatomy Epibdella squamula sp. nov. Proc. Cal. Acad. Sc., 3:109-136. Isun, N. 1936. Some new ectoparasitic trematodes of marine fishes. Zool. Mag. (Japan), 48:781-790. Jounston, T. H. 1929. Remarks on the synonymy of certain tristomatid trematode genera. Trans. Proc. Roy. Soc. S. Austral., 53:71-78. 1931. New trematodes from the Subantarctic and Antarctic, Austral. Jour. Exp. Biol. Med. Sc., 8:91-98. Jounston, T. H., and O. W. Tiecs 1922. New Gyradactyloid trematodes from Australian fishes, together with a reclassification of the superfamily Gyradactyloidea. Proc. Linn. Soc., N. S. Wales, 47:83-131. Jorpan, D. S., B. W. Evermann, and H. W. Crark 1930. Check list of the fishes and fishlike vertebrates of North and Middle America north of the northern boundary of Venezuela and Colombia. Rep. U. S. Comm. Fish., 1928, 2:1-670. MacCatium, G. A. 1913; a croceus nov. gen., Centralbl. Bakteriol. Parasit., 68:335- 1913. Further notes on the genus Microcotyle. Zool. Jahrb., Syst., 35:389-402. 1913. Notes on four trematodes of marine fishes. Centralbl. Bakteriol. Parasit., 70:407-416. No. 5 MESERVE: MONOGENETIC TREMATODES 73 MacCativuM, G. A. 1918. Notes on the genus Telorchis and other trematodes. Zoopath., 1:81-98. 1927. A new ectoparasitic trematode. Epibdella melleni, sp. nov. Zoopath., 1:291-300. Manter, H. W. 1934. Preliminary observations on trematodes from the Galapagos Islands and neighboring Pacific. Carnegie Inst. Wash., Year Book, 33:260-261. Monricetu, F. S. 1903. Per una nuova classificazione degli Heterocotylea, Monit. Zool. Ital., 14:334-336. 1907. Il genere Encotyllabe Diesing Atti Roy. Inst. Incorrag. Napoli., 59:23-35. Opuner, T. 1905. Die Trematoden des arktischen Gebietes. Fauna Arctica, 4:291-372. Parona, C., and A. Peruaia 1889. Di alcuni Trematodi ectoparassiti di pesci marini, Nota preventiva. Anna. a el Mus. Civ. Storia Nat. Genova, ser. 2., 7:740-747. 1890. Intorno ad alcune Polystomeae e considerazioni sulla sistematica di questa famiglia. Atti Soc. Ligust. sc. Nat., 1:225-242. Pocue, F. 1925. Das System der Platodaria. Arch. Naturgesch., 91:1-458. Price, E. W. 1934. New monogenetic trematodes from marine fishes. Smith. Inst. Miscel. Coll., 91:1-3. 1936. North American monogenetic trematodes. George Wash. Univ. Bull. Summaries of Doctoral Theses, 1934-36. 1937. Redescriptions of two exotic species of monogenetic trematodes of the family Capsalidae Baird from the MacCallum collection, Proc. Hel. Soc. Wash., 4:25-27. Stites, C. W., and ArBerr Hassaty 1908. Index-Catalogue of Medical and Veterinary Zoology. Trematodes and trematode diseases. Hyg. Lab. Bull. No. 37. YAMAGUTI, S. 1934. 7. Studies on the helminth fauna of Japan. Pt. 2. Trematodes of fishes, I. Trans. and Abstr., Jap. Jour. Zool., 5:249-541. 1937. Studies on the helminth fauna of Japan. Pt. 19. Fourteen new ecto- parasitic trematodes of fishes. (Pub. by author.) Lab. of Parasitol., Kyoto Imp. Univ., pp. 1-28. ; ‘ iM 7 f * % bei’ LA 4 yl ieeae ie ¥ Fi ay » i . ° 7 ’ mba iis! 6 « ‘ . ‘ + s J ; ‘ . ;: + e 4 ° ° Te a o* e @ e & e * @ « ma . « 7 7 * . ® » ° * o\ % . s « * / 4 . P ‘ * ° No.5 MESERVE: MONOGENETIC TREMATODES 75 EXPLANATION OF PLATES All figures were drawn with the aid of a camera lucida. The scale is indicated in the drawings. Abbreviations are as follows: d vas deferens p penis cirrus pr prostate gland e excretory bladder prr prostatic reservoir ep excretory pore sr seminal receptacle ga genital atrium t testis gc giant cell ut uterus gp genital pore v vagina gic genitointestinal canal vil vitelline gland 7 intestine vr vitelline reservoir m mouth vs vaginal spine mg shell gland x structure of problematic od oviduct nature ot ootype vd common yolk duct ov ovary g gland of Goto 76 GC INO = COON AKNH ALLAN HANCOCK PACIFIC EXPEDITIONS BARES Benedenia isabellae. Ventral view. Egg of B. isabellae. Benedenia adenea. Ventral view. Ege of B. adenea. Benedenia anadenea. Ventral view. Larval hook of B. anadenea. Gland cell of posterior haptor of B. anadenea. Nonglandular cells of posterior haptor of B. anadenea. Entobdella muelleri. Ventral view. VoL. 2 no. 5 MESERVE: MONOGENETIC TREMATODES pL. 4 or ee 8P f : . pr ot = ov [= 3 i=} t g wwe 78 Fic. Fic. Fie. Fie. Fic. Fic. Fic. Fic. Fic. Fic. Fic. Fic. 10. 11. 12 o. 1g: 14. 15. 16. 7s 18. 19% 20. ZN. ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 PLATE 5 Encotyllabe pagrosomi MacCallum. Lateral view. Small hook of posterior haptor of E. pagrosomi. EF. pagrosomi. Enlarged anterior end. Dichdophora caulolatili. Ventral view. Lateral view of chitinous skeleton of D. caulolatili. Ventral view of cirrus and cirrus hooks of D. caulolatili. Heterobothrium ecuadori. Ventral view. Egg of H. ecuadori. Egg of H. ecuadori. Chitinous skeleton of posterior sucker of H. ecuadori. Heterobothrium galapagensis. Ventral view. Chitinous skeleton of H. galapagensis. The lateral pieces are paired; only one half of each pair is shown. MESERVE: MONOGENETIC TREMATODES Pies) Fic. Fic. Fic. Fic. Fic. Fic. Fic. Fic. Fic. Fic. Fic. Fic. Fic. Fic. Fic. DS BD BD BHD PbO DH & Yd wa we S 0 WwW Oo WO WH is) nN wR bo Se EUs Ww bd — me ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 PEATE 6 Hexostoma cuthynm. Ventral view. Egg of H. euthynni. Small posterior hook of H. euthynni. Mazocraes macracanthum. Ventral view. Posterior end of M. macracanthum, showing hooks. Chitinous skeleton of posterior sucker of M. macracanthum Chitinous skeleton of posterior sucker of M. macracanthum. Ventral view of cirrus of WM. macracanthum. Microcotyle priacanthi. Dorsal view. Armature of genital atrium of M. priacanthi. Chitinous skeleton of posterior sucker of M. priacanthi. Gotocotyla acanthocybu. Dorsal view. Dorsal view of G. acanthocybii. Vitellaria are diagrammatic Chitinous skeleton of posterior sucker of G. acanthocybu. Posterior end of G. acanthocybu showing hooks. PL. 6 MONOGENETIC TREMATODES . . MESERVE LT a) V CY TA 2o%o oee & IG Se e6 ° Fi S006 S% oe, 900a99900009099%" a as We SS A) 0.05mm o.o5mm o°5 B32? 9 DR”) 9 BID eters 82 Fic. Fic: Fic. Fic. Fic. Fic. Fic. ls 38. 39). 40. Al. 42. 43. ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 PEATE 7 Gotocotyla elagatis. Ventral view. Posterior end of G. elagatis showing hooks, Ventral view. Chitinous skeleton of posterior sucker of G, elagatis. Anterior end of G. elagatis showing mouth, anterior suckers, genital pore and pigment granules. Thoracocotyle paradoxica. Ventral view. Posterior end of 7’. paradoxica showing hooks. Chitinous skeleton of posterior sucker of 7. paradoxica. PL. / 4] MONOGENETIC TREMATODES . 0.3mm MESERVE oe) a Ere, Fic. Fic. Ere: Fic. Fic. Fie. Fic. Fic. Fic. Ines Fic. Fic. Fic. Fic. 52. ALLAN HANCOCK PACIFIC EXPEDITIONS VoL. 2 PLAGE 8 Axine oligoplitis. Dorsal view. Chitinous skeleton of posterior sucker of A. oligoplitis. Ovary and reproductive ducts of 4. oligoplitis. Ventral view. Genital atrium of J. oligoplitis showing hooks. Ventral view. Axine seriolae, ventral view of adult vitellaria and testicular re- gion diagrammatic. Chitinous skeleton of 4. seriolae. The lateral pieces are paired; one half not shown. Ventral view of ovary and reproductive ducts of A. seriolae. Eggs of 4. seriolae. Anterior end of 4. seriolae. Ventral view. Axine elongata. Dorsal view. Eggs of 4. elongata, one of which has a detached operculum. Anterior end of 4. elongata showing anterior suckers and genital pore. Ventral view. Ventral view of genital pore of 4. elongata. Chitinous skeleton of posterior sucker of 4. elongata. Dorsal view of ovary and reproductive ducts of 4. elongata. NETIC TREMATODES MONOGE . . MESERVE Lv) 45 an < PaO on 9, OS ONAN NT RD O° SOOH HOH O” ars °. 3529 9°65 eon | 005mm QYO 004mm ree 0.05.mn) 49 0.0o5mm LY 005mm 86 Does =. 00; Selle £162; 163. oy sO: sHOG: OTe ;. 68. 3 62. 2 70; ee Us mare ws: . 74, ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 BGA 9 Axine aberrans Goto. Dorsal view. Pseudaxine mexicana. Ventral view. Chitinous skeleton of posterior sucker of P. mexicana. Upper end of vas deferens of P. mexicana showing hooks. Posterior hooks of P. mexicana. Protomicrocotyle pacifica. Posterior haptor not shown. Ventral view. Chitinous skeleton of posterior sucker of P. pacifica. Posterior haptor and posterior suckers of P. pacifica. Cross section through genital atrium showing cirrus and atrial spines of P. pacifica. Large outer hook of posterior haptor of P. pacifica. Inner hook of posterior haptor of P. pacifica. Ventral view of anterior end of P. pacifica. P. pacifica. Ventral view. Hooks of genital atrium of P. pacifica Posterior hooks of P. pacifica. Vaginal opening and spines in enlarged upper end of vagina of P. pacifica. Ventral view. TODES MONOGENETIC TREMA’ MESERVE no. 5 ol as ee 0.05mm 63 0.05mm le Ne aaa OO, congisgress 8 Og) ‘ Oye? OggagadUboos: Roa: Wear nHow Bers 5 PL90%g A'S 20 @ GT 08 0 0320 00F00C00 8 Sd § Gos ar ESOS 6° 5 s Ye -ae OMadODVO aoe PP. Oo Vb at eee a: ee nea oo. © a 88 Fic. Fic. Fic. Fic. Fic. Fic. Fic. Fic. Fic. Ere: Fic. 84. 85. ALLAN HANCOCK PACIFIC EXPEDITIONS Von PLATE 10 Cestracolpa cypseluri, anterior end enlarged. Dorsal view. Chitinous skeleton of posterior sucker of C. cypseluri. Vaginal spine of C. cypseluri. Armature of genital atrium of C. cypseluri. Two ova of C. cypseluri from anterior end of ovary. C. cypseluri. Dorsal view. Cestracolpa yamagutu. Dorsal view. Armature of genital atrium of C. yamagutu. Vaginal spine of C. yamaguti. Chitinous skeleton of posterior sucker of C. yamagutu. Ovary and reproductive ducts of C. yamagutti. Dorsal view. Pr. 10 MESERVE: MONOGENETIC TREMATODES NO. 0.05mm 77 aati vue ( aA Cc Nit S00 re) ee 7 eae eee, 3 = Oe ares & SES <= Ifa, SS So ~ 4, i ETA, 8 ~ Serine — 2 = a - es DS (S =) Ea és Se — WO om A) ° es SSA “ %2 Bie A 6 4f= r ss wu oy wa od VAWwese AC Sui ee oimm Aang 94 84 bee, / / 2 / REPORTS ON THE COLLECTIONS OBTAINED BY THE HANCOCK PACIFIC EXPEDITIONS OF VELERO III OFF THE COAST OF MEXICO, CENTRAL AMERICA, SOUTH AMERICA, AND GALAPAGOS ISLANDS IN 1932, mn 1933, in 1934, my 1935, in 1936, AND In 1937. THREE NEW TREMATODES FROM THE GALAPAGOS MARINE IGUANA AMBLY RHYNCHUS CRISTATUS By PAUL T. GILBERT Tue University oF SOUTHERN CALIFORNIA PUBLICATIONS Attan Hancock Paciric ExpEpDITIONS VotumMe 2, NuMBER 6 IssuepD Marcn, 1938 Tue UNIvERSITY OF SOUTHERN CALIFORNIA PREss Los ANGELES, CALIFORNIA THREE NEW TREMATODES FROM THE GALAPAGOS MARINE IGUANA AMBLYRHYNCHUS CRISTATUS* (Wit Two Prates) Paut T. GILBERT University of Nebraska The trematodes described below were collected during the Allan Hancock Expedition to the Galapagos Islands in 1934, by Dr. H. W. Manter under whose direction this study was made. Three species of trematodes were secured from the marine iguana, Amblyrhynchus cristatus (Bell). All three species seem to represent new genera of Pronocephalidae. Two of the new genera are in the subfamily Pronocephalinae, and one in the subfamily Teloporinae. At present the family Pronocephalidae contains five subfamilies and consists of monostomes chiefly from marine turtles. There are thirteen species recorded from Chelone midas alone. Although no Pronocephalids are hitherto known from Lacertilia, it is not sur- prising that the trematodes of Amblyrhynchus should belong to this family since the food and habitat of this iguana are so much like those of marine turtles. This iguana lives along a rocky coast line and feeds upon seaweed. The type specimens of the three new species described are de- posited in the United States National Museum and paratypes are in the collection of The University of Southern California. Famity: PRONOCEPHALIDAE Looss, 1902 aw SUBFAMILY: PRONOCEPHALINAE Looss, 1899 a tan Iguanacola navicularius, new genus, new species [ae gS ket (Plate 11, figs. 1-4) j jk Ra Host: Amblyrhynchus cristatus Lt. eee Location: Intestine C7 4s a Locality: Albemarle Island at ay The following description is based on a study of four mounted and two sectioned specimens. Of the four toto mounts only two were * Studies from the Zoological Laboratories, University of Nebraska, No. 194. [91] 92 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 extended enough to give complete measurements. When extended the body is elongate, about four and one-half times longer than wide, flattened, and without spines or special skin glands. It is evenly rounded posteriorly and anteriorly. One extended specimen measured 8.795 mm. in length and 1.993 mm. in width, the widest portion being near the posterior end of the body. Near the anterior end is a collar in the form of a muscular ridge which is comparatively weak when contrasted with this structure in other genera of the subfamily. It is interrupted ventrally by a concave, oval depression which occu- pies the median half of the ventral surface of the anterior third of the body. When contracted the body is boat shaped (fig. 3). The anterior ventral depression then seems to extend the entire length of the worm. A contracted specimen measured 6.629 mm. in length. The body is highly muscular with an abundant concentration of transverse bundles in the anterior region, especially in the region of the ventral depression. The oral sucker measures 0.6 mm. in width and 0.57 mm. in length. The esophagus is slender with an expanded anterior portion, and measures 0.375 mm. in length. The ceca are narrow and extend nearly to the posterior end of the body, bowing medianly in the region of the testes. The walls of the ceca are irregular with small outpocketings hardly long enough to be considered branches. The testes are large and strongly lobed, lying opposite each other near the posterior end of the body. The intestinal ceca pass between the testes and overlap the inner margins of them ventrally. Each testis is divided into about seven large lobes, some of which may be subdivided to form secondary lobes. The tubular seminal vesicle is voluminous, lying free in the parenchyma, passing from the posterior fourth of the body to the posterior portion of the large cirrus sac located about at mid-body. The extreme posterior portion of the vesicle is straight but as it passes anteriorly it becomes coiled. The cirrus sac is large and divided by a constriction into two parts which form an angle of ninety degrees with each other. The posterior half of the sac passes diagonally forward from the seminal vesicle to the inner edge of the right cecum. The anterior half of the sac returns to the mid-line and genital pore (fig. 1). The prostatic por- tion of the cirrus sac occupies about nine tenths of the whole sac and is made up of large cells which appear to project into the central lumen. The cirrus is in the form of a muscular papilla projecting No. 6 GILBERT: THREE NEW TREMATODES 93 nipple-like into a terminal chamber which surrounds the cirrus except at its basal portion (fig. 2). The ejaculatory duct is thick-walled, but narrow. At its distal end it communicates with the terminal chamber; at its proximal end it joins a narrow, flattened chamber which appears to be a horizontal widening of the ejaculatory duct at the base of the cirrus (fig. 2) and communicates posteriorly with the lumen of the prostatic region. The genital pores are separate, the male pore lying slightly to the right of the female pore. Both pores are located just anterior to mid-body level and a little to the left of the median line. The ovary is slightly lobed, lying in the median line just anterior to the testes. The large shell gland complex lies close to the posterior margin of the ovary. The gland is surrounded by a capsule of con- nective tissue. There is no seminal receptacle. Laurer’s canal is pres- ent, extending from the anterior level of the shell gland to the dorsal surface, a little anterior to the ovary. The large follicles of the vitellaria are arranged in a linear series lateral to the ceca, and at the outermost boundaries of the uterine coils, fifteen on the right side and seventeen on the left. These follicles extend from the an- terior level of the testes to the anterior level of the seminal vesicle (fig. 1). The uterus extends from the region of the ovary in trans- verse coils which overlap the ceca, to the very weak metraterm to the left of and slightly posterior to the anterior portion of the cirrus sac. The small eggs have thick shells which continue terminally to form a single long filament at each pole (fig. 4). The eggs measure 18 to 22 by 8 to 13 w. The longest filaments are 63 » and are found on eggs in the anterior portion of the uterus. The excretory pore is on the dorsal median surface, near the posterior end of the body. The excretory vesicle is narrow, and ex- tends to the level of the shell gland where it branches to form two limbs which continue anteriorly, lateral to the ceca. Blunt projec- tions or pockets are present on the outer margins of the limbs and the inner margins give off numerous branches which not only anas- tomose with branches from the opposite limb, but also with other branches anteriorly and posteriorly, forming a network of excretory vessels especially in the anterior half of the body. The limbs of the excretory vesicle do not unite at their anterior extremities, but end bluntly at the level of the esophagus (fig. 1). 94 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 GENERIC DIAGNOSIS OF IGUANACOLA Medium sized Pronocephalids, body smooth and elongate in extended forms, bearing a low muscular collar complete dorsally, interrupted ventrally by oval depression. Oral sucker subterminal; esophagus simple; intestinal ceca narrow, irregular, but without dis- tinct side branches. Genital pores separate, close together near inner edge of left cecum. Testes symmetrical, lobed, near posterior end of body; seminal vesicle long and coiled; cirrus small, conical, and muscular, in a terminal chamber. Ovary pretesticular, in median line; shell gland just posterior to ovary. Uterine coils overlap ceca. Vitellaria extracecal from anterior level of testes to posterior level of cirrus. Eggs with a long filament at each pole. Excretory vesicle Y-shaped with anastomosing branches. Parasitic in intestine of marine iguana, Amblyrhynchus cristatus. Type species: Iguanacola navicularius. SPECIFIC DIAGNOSIS OF IGUANACOLA NAVICULARIUS (Measurements in mm.) Body smooth, elongate, four and one-half times longer than wide, highly muscular, cup-shaped when contracted. Length 6.63 to 8.80, width 1.30 to 2. Oral sucker on ventral surface at anterior end, slightly wider than long, 0.6 wide, 0.57 long. Esophagus short with enlargement at anterior end. Ceca narrow, reaching nearly to pos- terior end of body, ventral to inner edges of testes, with short irregu- lar outpocketings on outer margins. Genital pores separate but close together, slightly to left of and anterior to mid-body. Testes with distinct lobes, symmetrical, near posterior end of body. Seminal vesicle coiled, free in parenchyma, extending from just anterior to testes to posterior end of cirrus sac. Cirrus sac large, about five times as long as wide, extending from seminal vesicle diagonally to margin of right cecum, and continuing diagonally in opposite direction to mid-line and genital pore; prostatic region large, occupying greater portion (about nine tenths) of cirrus sac, with strong constriction present in middle portion. Cirrus small, muscular, projecting nipple- like into terminal chamber which surrounds it except at basal portion. Ejaculatory duct communicates with anterior terminal chamber of cirrus, and posteriorly with flattened sinus at base of cirrus. Ovary No. 6 GILBERT: THREE NEW TREMATODES 95 slightly lobed, on median line anterior to testes; shell gland complex well developed, just posterior to ovary; seminal receptacle absent; Laurer’s canal present; vitellaria of fifteen to seventeen large follicles on each side, extending lateral to ceca from level of testes to posterior level of cirrus sac. Uterus in transverse coils overlapping ceca from ovary to female pore; eggs 18 to 22 by 8 to 13 yp, thick shells, with single filament at each pole. The genus name is for the host. The species name is from navicu- la (small boat), which describes the boat-shaped body in contracted specimens. Comparisons. This genus combines characteristics of several other genera in the subfamily. The magnitude of the prostate, the constriction present in this organ, and the relatively small cirrus and large cirrus sac appear to be new characteristics. The excretory sys- tem is apparently like that of Epibathra Looss, 1901 but most of the other characteristics seem more related to Cricocephalus Looss, 1899; Adenogaster Looss, 1901; and Pleurogonius Looss, 1901. Cricocephalus, however, has definite branches on the ceca, posterior terminal glands on the body, a simple excretory system, no ventral depression, and a much smaller prostate gland. Adenogaster has a large prostate gland but it fills only half of the cirrus sac; the cirrus is long, and the seminal vesicle lies coiled in a small area near the prostate and does not continue posteriorly. Furthermore, numerous glands cover the ventral surface of the body in Adenogaster but are lacking in Iguanacola. Pleurogonius differs from Iguanacola in that the limbs of the excretory vesicle do not have side branches and unite anteriorly, the cirrus is simple, and the seminal vesicle not so long. Myosaccus amblyrhynchi, new genus, new species (Plate 11, figs. 5-8) Host: Amblyrhynchus cristatus Location: Intestine Locality: Albemarle Island The following description is based on a study of five mounted, and one sectioned specimen. The smooth, equally broad, weakly muscular body measures 4.66 by 1.77 mm. There are two papillae at the posterior end. The weak muscular collar near the anterior end of the body is complete both 96 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 dorsally and ventrally, and extends as a small protuberance at each side. The oral sucker is subterminal, 0.33 by 0.34 mm. Its opening is just anterior to the muscular ridge. Immediately posterior to the collar is a deep ventral depression extending only a short distance posteriorly. The esophagus is short and simple, measuring 0.15 mm. in length. The ceca are voluminous with broad outpocketings along their outer margins (fig. 5). The male and female pores are close together, opening ventrally on the left side of the body about one fourth the body length from the anterior end. The testes are in the extreme posterior end of the body. They are large, deeply lobed, and directly opposite each other. There are about eight primary lobes on each testis, but these may be broken up into secondary lobes. The seminal vesicle is a narrow, tightly coiled tube extending in the mid-body line from about the anterior end of the vitellaria to the base of the short cirrus sac (fig. 5). It connects with the cirrus sac by an uncoiled portion passing to the left from the mid-line. The cirrus sac lies almost horizontally, and extends from the left side of the body to a point slightly beyond the inner margin of the left cecum. It is divided into two portions, one being wide, muscular, and prostatic, the other short, narrow, and containing the cirrus. The prostatic portion is broad and spindle- shaped with numerous small prostatic cells surrounded by a wide sheath of thick longitudinal muscle bands (fig. 6). The short stout cirrus is surrounded by a thin band of longitudinal muscles which are continuous with some of those of the larger portion of the sac. The female pore lies to the left of the male pore. The ovary is slightly lobed, and lies to the right of the mid-line immediately anterior to the right testis. The ovary is less than half as large as the right testis. The large shell gland lies on the mid-line between the anterior portions of the testes. There is no definite membrane present around the shell gland. Laurer’s canal was not seen. There is no seminal receptacle. The large irregular follicles of the vitellaria are definitely arranged in a single, linear, extracecal series on each side, extending from the anterior level of the testes to the posterior level of the seminal vesicle. There are about sixteen follicles on the right side, and eighteen on the left. The yolk ducts extend from the anterior vitellaria posteriorly passing to the shell gland at the level of the ovary. The uterus terminates in a very weak metraterm (fig. 6). The eggs measure about 63 » in length and 29 » in width. Ap- no. 6 GILBERT: THREE NEW TREMATODES 97 proximately five long filaments, about 133 » in length, extend from each pole of the egg. The excretory pore is found on the median dorsal surface near the posterior end of the body. The excretory vesicle is Y-shaped, forking near the shell gland. The crura extend to the region of the esophagus where they end blindly. Blunt, volumi- nous branches are present mostly on the outer margins of the limbs. GENERIC DIAGNOSIS OF MYOSACCUS Medium sized Pronocephalids; body smooth, truncated, muscula- ture weak; collar complete. Ventral anterior depression present. Oral sucker subterminal; esophagus simple; intestinal ceca voluminous with short blind outpocketings. Genital pores separate, near left body edge. Testes opposite, lobed, in posterior end; seminal vesicle narrow, coiled anteriorly; cirrus sac short, divided into larger, very muscular prostatic region, and smaller cirrus region. Ovary pretes- ticular, to right of mid-line. Uterine coils intercecal. Vitellaria extra- cecal, from anterior level of testes to posterior level of seminal vesi- cle. Eggs with many long filaments. Excretory vesicle Y-shaped with many secondary branches on crura. Crura not uniting anteriorly. Parasitic in intestine of marine iguana, Amblyrhynchus cristatus. Type species: Myosaccus amblyrhynchi. SPECIFIC DIAGNOSIS OF MYOSACCUS AMBLYRHYNCHI (Measurements in mm.) Body measuring 3.270 to 4.665 by 1.455 to 1.776. Anterior end with weak muscular collar complete. Short ventral depression pres- ent. Body rounded anteriorly, and bluntly rounded posteriorly with terminal papillae present. Oral sucker subterminal and ventral, slightly wider than long. Esophagus short, simple. Ceca voluminous, to near posterior end, bowing towards median line in anterior fifth, and between testes, short outpocketings present, no branches. Geni- tal pores separate but close together near left body edge, one fourth from anterior end. Testes distinctly lobed, directly opposite each other near posterior end. Seminal vesicle narrow, coiled free in paren- chyma from level of genital pores to level of second or third uterine coil, Cirrus sac divided, large portion containing narrow spindle- shaped prostate surrounded by wide bundles of longitudinal muscles; smaller portion containing small, stout cirrus with few longitudinal 98 ALLAN HANCOCK PACIFIC EXPEDITIONS vou. 2 muscles. Female pore to left of male pore. Ovary slightly lobed, to right of mid-line, anterior to testes. Shell gland posterior to ovary, median, well developed, without outer membrane. Seminal recep- tacle and Laurer’s canal apparently absent. Vitellaria in large irregu- lar follicles extending lateral to ceca from anterior level of testes to posterior level of seminal vesicle. Uterus in transverse coils, inter- cecal, from ovary to female pore. Eggs 59 to 63 » by 25 to 36 p, with many long filaments, about 133 » long, at each pole. Excretory vesi- cle Y-shaped, with numerous short branches on limbs. The generic name is from the Greek myo (muscle) and saccus (sac), descriptive of the very muscular cirrus sac. The species name is for the host. Comparisons. Myosaccus differs from Iguanacola in its body form, cirrus sac, and excretory system. Epibathra Looss, 1902 differs in that the cirrus is not divided, the prostate is not surrounded by muscles, and the collar and excretory system are very different. Adenogaster Looss, 1901 has a divided cirrus, and the position of the ovary, testes, and shell gland are almost the same as in Myo- saccus. Adenogaster, however, differs in its long simple prostate, the lack of a muscular sheath about the prostate, the absence of pos- terior papillae and the presence of four rows of ventral glands. The cirrus of Diaschistorchis Johnston, 1913 resembles this genus in its musculature, but almost all other characters are different. Pyeloso- mum Looss, 1899 has a horizontal cirrus sac but it is undivided and thin-walled and no papillae occur at the posterior end of the body. SUBFAMILY: 'TELOPORIINAE STUNKARD, 1934 Cetiosaccus galapagensis, new genus, new species (Plate 12, figs. 9-11) Host: Amblyrhynchus cristatus Location: Intestine Locality: Albemarle Island The body is very long and narrow, measuring 7 to 13 mm. in length by 1 to 1.3 mm. in greatest width. The width is greatest in the anterior fourth of the body. The body is without spines or pos- terior papillae. The excretory pore is located on a muscular protu- No. 6 GILBERT: THREE NEW TREMATODES 99 berance at the extreme posterior end. In extended compressed speci- mens the collar is not visible. In contracted specimens there is a weak muscular collar which projects slightly laterally and dorsally, but is interrupted ventrally by a depression. The oral sucker is mus- cular, subterminal, and measures 0.22 to 0.4 mm. long and 0.30 to 0.42 mm. wide. The mouth is located in the posterior portion of the oral sucker. The esophagus is short, slightly less than the length of the oral sucker. The ceca are simple, narrow, and unbranched, extending to the posterior fourth of the body. Near their posterior ends the ceca seem to twist considerably, resembling a corkscrew. The ceca do not unite posteriorly, nor bow in at the testes. The common genital pore is located on the median line, one fourth the body length from the anterior end. The testes are located in the posterior half of the body, somewhat anterior to the termina- tions of the ceca. They are round or oval, unlobed, intercecal, tan- dem, separated by about half their length. The cirrus sac is spherical and surrounded by a layer of circular muscles. The seminal vesicle opens into the posterior end of the cirrus sac, and a long ejacula- tory duct passes through it. The cirrus is in the form of a stout papilla projecting into a large chamber which surrounds all but its basal portion. Longitudinal muscles line the cirrus chamber and also cover the outer surface of the papilla (cirrus). The chamber of the cirrus sac opens on the ventral surface of the body through the geni- tal pore. The seminal vesicle is a voluminous, highly coiled tube to the right of and posterior to the cirrus sac. It extends posteriorly about one and one-half times the length of the cirrus sac. The more anterior, prostatic portion of the vesicle is enlarged and coiled. This part of the vesicle possesses an outer layer of longitudinal muscle, and numerous prostatic cells which fill its greater portion (fig. 10). The posterior portion of the vesicle is without the heavy muscle layer or prostatic cells, and is the true seminal vesicle. The ovary is located on the mid-line just anterior to the anterior testis. It is rounded, unlobed, and slightly smaller than the testes. The shell gland is large, lying posterior to, and in most specimens, a little to the right of the ovary. The gland is made up of many large cells radiating about the oviduct which is coiled in the anterior por- tion of the gland. A definite sheath surrounds the gland. Laurer’s canal is long, and opens dorsally anterior to the ovary. The vitelline 100 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 follicles are closely grouped, about twenty-seven on each side, imme- diately ventral to the ceca, extending forward from the anterior bor- der of the ovary, for about four lengths of the ovary. The uterus is highly coiled, especially in the anterior region. It extends, between the ceca, from the ovary to the level of the genital pore. The an- terior portion of the uterus enters a moderately developed metra- term with thick glandular walls and a narrow internal layer of longi- tudinal muscles (fig. 10). The metraterm lies to the left of the cirrus sac, and tapers to the genital pore. The eggs measure 19 to 23 by 9 to 11 p», with a single long filament at each pole. The filaments are about 83 to 106 p in length. The excretory pore is at the extreme posterior end of the worm, and is surrounded by muscles. The excretory vesicle is unusual. It is very large and voluminous, filling at least the posterior fifth of the body (fig. 9). It has thick glandular, highly folded walls. The vesicle divides just posterior to the terminals of the ceca. In all specimens the right limb was greatly enlarged in the region of the division. The limbs pass anteriorly, dorsal to the ceca as irregular, unbranched, narrow tubes which unite dorsal to the oral sucker. Each limb twists upon itself to form a complete circle at the level of the sucker before uniting with the other limb. GENERIC DIAGNOSIS OF CETIOSACCUS Elongate Teloporiinae. Body smooth, collar weak, anterior ven- tral depression present. Both ends of body rounded. Ceca simple. Genital pore median, one fourth body length from anterior end. Testes round or oval, smooth, intercecal, median and tandem, in posterior half of body. Seminal vesicle coiled, entirely anterior to mid-body, just posterior to cirrus sac, with anterior prostatic por- tion. Cirrus papilla-like in terminal chamber. Ovary spherical me- dian, pretesticular. Shell gland large. Seminal receptacle absent. Laurer’s canal present. Uterus intercecal, preovarian. Eggs with single polar filament at each pole. Excretory vesicle voluminous, walls highly folded, in posterior fifth or more of body, limbs simple and uniting anteriorly. From intestine of marine iguana, 4Ambly- rhynchus cristatus. Type species: C. galapagensis. No. 6 GILBERT: THREE NEW TREMATODES 101 SPECIFIC DIAGNOSIS OF CETIOSACCUS GALAPAGENSIS (Measurement in mm.) This species has the following characters in addition to those mentioned above: size 7 to 13 by 1 to 1.3. Oral sucker 0.30 to 0.42 in diameter. Esophagus short, ceca narrow, twisted posteriorly, end- ing separately. Testes separated by a short distance. Cirrus sac spherical containing a male genital papilla projecting into a terminal chamber; ovary separated from anterior testis by a short distance; shell gland posterior to ovary, with enclosing membrane; vitellaria lateral just anterior to ovary, about twenty-seven follicles on each side; metraterm extending posterior to cirrus sac; eggs 19 to 23 by 9 to 11 pw. Host: Amblyrhynchus cristatus. The genus name Cetiosaccus is from cetio (monstrous) and saccus (vesicle) referring to the very large excretory vesicle. The species name galapagensis is for the locality. Comparisons. The only closely related genus is Teloporia with which Cetiosaccus agrees in its simple ceca, shape and position of the testes and ovary, lack of seminal receptacle, its median genital pore and egg shape. But Cetiosaccus differs very widely from Telo- poria in many respects, especially: the excretory system with its glandular vesicle and united crura; the spherical cirrus sac and pe- culiar genital papilla; and the compactly coiled seminal vesicle of two regions. 102 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 LITERATURE CITED Fuxu1, Tamao 1933: Teloporia (Tremat.)=Opisthoporus. Zool. Anz., 103:332-333. Jounston, S. J. 1913: Looss, A. 1899. 1901. 1902. On some Queensland trematodes, with anatomical observations and descriptions of new species and genera. Quart. Jour. Micros. Sci., 59: 378-383. Weitere Beitrage zur Kenntniss der Trematoden—Fauna Aegyptens. Zool. Jahrb., Syst., 12: 521-748. Notizen zur Helminthologie Egyptens, IV, Ueber Trematoden aus Seechildkréten der egyptischen Kiisten. Cent. Bakt. Parasit., 30: 555-568, 618-625. Ueber neue und bekannte Trematoden aus Seechildkréten. Zool. Jahrb., Syst., 16: 411-894. Price, Emmetr W. 1931. Redescription of two species of trematode worms from the MacCallum collection with a note on the family Pronocephalidae. Proc. U. S. Nat. Mus., 78: 1-10. StunKARD, Horace W. 1930. 1934. Morphology and relationships of the trematode Opisthoporus aspi- donectes. (MacCallum, 1917) Fukui, 1929. Trans. Amer, Micros. Soc., 49: 210-219. On the trematode genus 7¢loporia Fukui, 1933. Zool. Anz., 106: 218-220. fee —- No.6. 3 GILBERT: THREE NEW TREMATODES 103 EXPLANATION OF PLATES All figures were drawn with the aid of a camera lucida or projector. The value of the projected scale is indicated in each figure. The following abbreviations are used: (CT Pa a Cee A ae AE cirrus GSA Rs ri SUMS Isaac GINSBURG Bureau of Fisheries, Washington, D.C. Vee . Five new species of gobies obtained in the course of several expedi- tions made by Captain G. Allan Hancock, to the Gulf of California in 1936 and 1937, and to the Secas Islands, off Panama, incidental to an investigation of the Galapagos Islands in 1935, are here described. In addition I take this opportunity to offer brief diagnoses of three other new species from the Gulf of California, discovered by me in an extensive investigation of American gobies. They will be treated more fully in a future paper which will contain revisions of their respective genera. One new genus and one new subgenus, based on two of the species, are established. All proportional measurements stated below refer to percentages in the standard length. The given length of specimens refers to the total length, including the caudal fin, unless otherwise specified. Chriolepis zebra, new species Description—Form elongate, body compressed, head strongly de- pressed. Snout notably blunt when viewed from dorsal aspect. Mouth moderately oblique, subsuperior, a horizontal through distal margin of upper lip passing approximately through upper margin of pupil; lower jaw projecting. Maxillary short, its end falling under anterior margin of pupil. Interorbital of medium width. Tongue very moderately emargi- nate. Teeth in outer and inner rows in both jaws strongly enlarged; one or two irregular rows of much smaller teeth in between at symphy- sis, one row posteriorly; in lower jaw outer row confined to front, the teeth subequal, inner row extending about half the distance from symphysis to angle of mouth, the last two teeth larger than others, caninoid, the small teeth continued posteriorly in a single row to angle of mouth; in upper jaw outer row extending nearly to angle of mouth, the posteriormost three or four teeth somewhat smaller, the others sub- equal, inner enlarged teeth confined to front. No spine at angle of pre- 1 Published by permission of the U.S. Commissioner of Fisheries. [ 109] 110 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 opercular margin. Isthmus wide, attachment of branchiostegal mem- brane at lower angle of pectoral base. Posterior part of body and caudal peduncle covered with scales, in about 17 oblique rows from a vertical through base of fifth dorsal ray to end of hypural, some nonimbricate scales extending a little more forward, to a vertical through base of second dorsal ray; the anteriormost scales very small, gradually increas- ing in size, the posteriormost scales large; scales cycloid, except a few of the larger scales in the last three or four rows ctenoid; a row of four scales on caudal, at its base; the two outer scales conspicuously large, ovoid, the lateral spinules markedly long, decreasing gradually in length toward a median line, the spinules on outer side somewhat larger than those on inner side; the two inner scales in the row much smaller and cycloid. (In the single specimen examined only one smaller, cycloid scale is present next to the lower, large scale, on both sides. However, a bare space is present to fit exactly another such small scale, and the upper of the two scales evidently has fallen off.) First dorsal with 7 flexible spines, none especially prolonged. Second dorsal and anal with 10 rays; posterior anal rays just reaching a vertical through end of hypural, those of dorsal falling slightly short. Pectoral with 18 rays; its tip falling on a vertical a little in front of origin of second dorsal. Ventrals completely separated, the tip falling a little short of anus. Caudal of moderate length, pointed. Cross-banded color pattern sharply marked; ground color light straw yellow; body crossed for its entire width by seven dark bands from origin of first dorsal to near base of caudal; color of bands generally a little more intense at lateral margins; the bands only a little narrower than the interspaces, except last band markedly narrower than others; a more diffuse band directly behind base of pectoral, nearly interrupted at middle of body; two similar bands on dorsal aspects of nape, con- tinued and becoming narrower on side of head, the posterior one on posterior part of opercle, rather diffuse, the anterior one on anterior part of opercle, narrower, more intensely pigmented, curving forward and becoming broader on under side of head over branchiostegal mem- brane; two transverse, parallel, approximated, rather narrow, very dark bands on interorbital space, interrupted by eye and continued below eye, the posterior one making a broad curve on cheek, convex posteriorly, the anterior one nearly vertical, under anterior margin on pupil, each extending to ventral aspect of head to nearly meet its fellow from oppo- site side, both becoming broad and more diffuse on ventral aspect of NO. 7 GINSBURG: NEW SPECIES OF GOBIOID FISHES 111 head; a band, similar to the two on interorbital, from anterior lower quadrant of eye, extending obliquely forward to upper lip; chin and upper lip dark; caudal light, crossed by four very dark, broad, curved bands, the anterior one, at its base, very broad, concave posteriorly, the others gradually decreasing in width, the second and third somewhat sinuous, the fourth convex posteriorly; second dorsal with very narrow dark streaks running downward and backward; anal dusky, the pigment increasing in intensity from its base distad, the margin hyaline; a dark, diffuse blotch at lower part of fleshy pectoral base; a diffuse, obliquely elongate blotch on upper rays, near their base; rest of pectoral, ventral and first dorsal light, devoid of chromatophores. Measurements—Male 27 mm (the only specimen examined ). Cau- dal 31, ventral 26.5, pectoral 26.5, depth 18.5, least depth of caudal peduncle 13.5, head 30, postorbital part of head 16, maxillary 10.5, snout 7, eye 7.5, interorbital 3, antedorsal distance 40.5. Holotype-—In Hancock Coll. San Gabriel Bay, Espiritu Santo Island, Gulf of California; shore collecting; March 7, 1937. Distinctive characters and relationship.—This species is easily dis- tinguished from all known American eleotrids by its striking, sharply marked, banded color pattern. It is rather intermediate in its squama- tion between Chriolepis minutillus Gilbert and Gymneleotris seminudus (Ginther), and largely bridges the gap between those two genera with respect to the squamation, the only substantial character hitherto em- ployed for their separation. It has the characteristic row of four scales on the caudal and some large ctenoid scales at the posterior part of the caudal peduncle, like C. minutillus, and it also has smaller cycloid scales anteriorly, like G. seminudus. Unlike the latter species, it lacks mucous pores and the interorbital is not notably wide. In this respect it agrees with C. minutillus and of the known American eleotrids it is structurally nearest to that species. The difference in the squamation together with the strikingly distinctive color pattern shows that minutillus and zebra are widely divergent, to an extent to be placed in distinct subgenera at least, and a new subgenus is therefore established for zebra. Eleotriculus, new subgenus Genotype.—Chriolepis zebra, new species. A definition of the subgenus is included in the description of the genotype. How it differs from the typical subgenus is discussed above in comparing the two genotypes. 112 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 Coryphopterus urospilus, new species Description—Form moderately elongate; body compressed, rather stout; head subtriangular in cross-section, the height directly behind eyes subequal to the greatest width at same point. Mouth rather small, terminal, a horizontal through distal margin of upper lip passing ap- proximately through lower margin of pupil; lower jaw about equal to upper anteriorly. Maxillary rather short, its end falling under anterior margin of pupil in male, slightly short of that point in female. An elongate, soft, pad-like translucent area present under anterior half of eye. Tongue entire, rather broad. Teeth in narrow bands of about four rows at symphysis, tapering to two rows posteriorly; teeth in outer and inner rows moderately enlarged; in upper jaw outer row extending to angle of mouth, a few enlarged teeth in inner row at symphysis; in lower jaw outer row confined to front, enlarged teeth in inner row extending a little farther backward; no caninoids. Shoulder girdle with- out papillae. A rather feebly developed, short, fleshy ridge in front of spinous dorsal, sometimes hardly perceptible. Scales on body ctenoid, large, in 25-26 oblique rows to base of caudal; anterior boundary of scales marked by a line extending approximately from origin of first dorsal to upper posterior angle of opercle; no scales on antedorsal dis- tance in front of that line, none on side of head; rather large cycloid scales on base of pectoral, on throat and on midline of belly. First dorsal with 6 flexible spines (in all 8 specimens), the fin rather high, but none especially prolonged, the third or fourth reaching base of first to third ray of second dorsal in male, somewhat lower in female. Second dorsal with 10 rays (in all 8); anal rays usually 10 (in 6), often 9 (in 2); posterior dorsal rays in the larger males reaching a vertical through end of hypural or falling a little short, in smaller males and females falling considerably short; those of anal not quite reaching as far back as those of dorsal. Pectoral with 19 (in 4) or 20 (in 4) rays, all connected by an interradial membrane, its posterior margin reaching a vertical through base of second or third dorsal ray. Ventral with the interspinal membrane of medium development, posterior margin of fin reaching slightly past anus in male, reaching anus or falling a little short in female. Caudal of medium length, truncate. Body with longitudinal rows of small dark spots; five rows on lateral aspect of body, four on caudal peduncle; spots in lower two rows some- what larger and darker, spots in upper three rows often connected by faint lines, forming a network effect; the spots, especially those in the NO. 7 GINSBURG: NEW SPECIES OF GOBIOID FISHES 113 two lower rows, characteristically lighter in the center, darker around the periphery; a row of eight rather diffuse, elongate blotches saddled on back from origin of first dorsal to base of caudal; dorsal aspect of nape with five irregular longitudinal rows of small, more or less elon- gate spots; side of head with three lengthwise bands; a band on a line with middle of eye, usually somewhat interrupted and nearly continuous with fourth from lowermost row of spots on body; a band from lower posterior margin of eye running somewhat obliquely to upper posterior part of opercle; a third band from posterior end of maxillary, some- what converging posteriorly with, but not meeting, middle band; two or three blotches in a row, one behind the other, on upper part of pectoral and its fleshy base, directly behind the bands, sometimes the bands and blotches nearly continuous; a similar blotch on lower part of fleshy base; a sharply marked, very dark spot on base of caudal, directly below the median line; a very faint smudge over it, above the median line; fins more or less dusky, without spots, pectoral lightest. Holotype-—In U. S. Nat. Mus. San Jose Island, Pearl Islands, Panama; in tide pools; March 15, 1937; S. F. Hildebrand; male 4] mm. Paratypes—4 males 35-42 mm., 3 females 34-37 mm; obtained with the type. I wish to take this opportunity to express my sincere thanks to Dr. Hildebrand for turning over to me for study, the Gobii- dae obtained during 1935 and 1937 as a result of and incidental to his studies of the fish fauna of the Panama Canal locks. I also examined one small specimen, 23 mm., in the Hancock collec- tion. It is in bad condition but appears to belong to this species. Its fin ray counts are D. 10, A. 10, P. 20. The characteristic spot on the lower part of the caudal base is present. Feeble traces of the general color pattern as described above are discernible. The data for this specimen are: Tiburon Island, Gulf of California; March 28, 1937. Distinctive characters and relationship—Of the two known species of its genus, wrospilus differs from (Gobius) Coryphopterus nicholsit (Bean) in having fewer rays in the dorsal, anal and pectoral and in lacking a black band on the distal margin of the first dorsal. It is evi- dently most nearly related to and agrees with Coryphopterus glauco- frenum Gill in the fin ray counts and the form of the head and body. It differs in having the predorsal fleshy ridge poorly developed or nearly obsolescent, and in color. The color pattern is similar in both, but the differences are striking on direct comparison. The spots in the longi- 114 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 tudinal rows are smaller and better marked in urospilus, and there are more rows. The caudal base has the lower spot very intense and the upper very faint, while in glaucofrenum both spots are of equal intensity in color. Lythrypnus pulchellus, new species Description—Form moderately elongate, head and body well com- pressed. Mouth small, oblique, subsuperior, a horizontal through distal margin of upper lip approximately bisecting eye; lower jaw projecting. Maxillary short, its posterior end approximately under anterior margin of pupil. Tongue entire, narrow. Outer row of teeth in both jaws enlarged, approaching caninoids in size, widely spaced; inner teeth minute, in a narrow band. Shoulder girdle without papillae. No ridge or crest in front of dorsal. Isthmus moderate, attachment of gill mem- brane on a vertical approximately setting off anterior third of opercle. Scales ctenoid, about 28; none on antedorsal distance, side of head, base of pectoral, throat or midline of belly (many scales missing in type and nearly all missing in the three paratypes, and above description subject to correction). First dorsal with 6 flexible spines (in all 4 specimens) ; the first spine notably prolonged in large male, more moderate in smaller (to base of ninth ray in a male 22 mm, to base of third in a male 18 mm); second spine more moderately prolonged (reaching to base of fourth ray in 2 males 19 and 22 mm, to base of first ray in a male 18 mm) ; the first two spines not notably prolonged in female (25 mm). Dorsal rays usually 13 (in 3), sometimes 12 (in 1); anal rays 10 (in all 4); posterior rays falling more or less short of a vertical through end of hypural, those of dorsal usually extending slightly farther back than those of anal; in both fins a little longer in male than in female. Pectoral with 18 (in 1) or 19 (in 3) rays, all connected by membrane, its tip reaching a vertical through base of second to fourth dorsal ray. Ventral having the interspinal membrane of medium develop- ment, tip of fin reaching vent or origin of anal. Caudal short, rounded. Anal papilla of male rather well developed. Body and head cross-banded; 12-13 bands from origin of first dorsal to base of caudal; the bands narrower than the interspaces, the two sharply delimited except sometimes posterior ones on caudal peduncle; each band having a transverse, median, dark streak; interspaces nearly uniformly colored, except sometimes those on caudal peduncle; a similar band over base of pectoral continued around back from one side to the NO. 7 GINSBURG: NEW SPECIES OF GOBIOID FISHES 115 other, becoming more or less diffuse on fleshy base of fin; five similar bands on top of head and nape, nearly spaced the same as bands on body, the anteriormost one on interorbital space, these bands on dorsal aspect forming broad curves, convex posteriorly, from a lateral view appearing to run obliquely downward and forward at the back, becom- ing nearly vertical on side of head, one on opercle, one just behind eye, one under middle of eye and two hardly perceptible ones from anterior lower quadrant of eye running forward to maxillary. Measurements——Male, standard length 17.5. Depth 25, depth of caudal peduncle 15, head 30, postorbital part of head 17.5, maxillary 12.5, snout 8.5, eye 11, antedorsal distance 36.5. Holotype.—In Bingham Coll. Espiritu Santo Island, Gulf of Cali- fornia; male 17.5 mm in standard length. Paratypes——All three in Hancock Coll. San Gabriel Bay, Espiritu Santo Island, Gulf of California; March 7, 1937; 2 males 18-19 mm. Puerto Refugio, Angel de la Guarda, Gulf of California; March 20, 1937; female 25 mm. Distinctive characters and relationship.—This species is very closely related to (Gobius) Lythrypnus zebra (Gilbert) from the Pacific coast of Southern California and Lower California. A most striking difference shown by the specimens compared, is found in the color pat- tern. The narrow cross bands in pulchellus are divided by a median, narrow, clear-cut, dark streak, which under the microscope shows defini- tive chromatophores, while the areas on either side of the streak are either uniformly dusky or of a plain light color; in zebra the definitive chromatophores spread out and what represents the clear cut dark streak of pulchellus becomes diffuse to cover nearly the entire cross- band. Again, the interspaces in pulchellus are uniformly colored, except some of the posterior ones, while in zebra the chromatophores in the interspaces are more concentrated along a transverse median area. In gross effect, the bands in pulchellus are lighter than or of approximately the same intensity as the interspaces, while in zebra the bands are darker than the interspaces. Of structural characters the only difference that I can point out now is the number of pectoral rays, but they intergrade in this character, 18-19 in pulchellus, 19-20 in zebra. It is evident that the corresponding populations on the Pacific coast proper and in the Gulf of California, respectively, should be recognized at least as distinct subspecies. However, the specimens examined are not 116 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 in good enough condition to permit the comparison of characters that are of importance in distinguishing the species of Lythrypnus, namely, the length of the dorsal spines and the posterior rays in the dorsal and anal, and the number of scales. ‘he two populations are therefore tentatively recognized as distinct species, pending the comparison of more specimens in a better state of preservation. PARRELLA, new genus Genotype.—Parrella maxillaris, new species. A definition of the genus is included in the description of the geno- type. Parrella is structurally nearest to Microgobius. ‘The genotype differs from all known species of Microgobius by having large scales, fewer rays in the dorsal and anal, a subterete head, a notably more slender body and longer pectoral, and a different color pattern. ‘The most striking differences, however, are found in the distribution of the lateral line organs. These structures which are of considerable importance in classification will be considered in a systematic manner in a forthcoming paper. I take pleasure in naming this genus after Professor Albert E. Parr of Yale University. Parrella maxillaris, new species Description—Body notably slender, compressed; head subterete, the depth slightly less than the width. Mouth terminal, very moderately oblique, a horizontal through distal margin of upper lip passing approxi- mately through lower margin of eye; lower jaw equal anteriorly to upper. Maxillary long (at least in male), its posterior end falling only about a pupil’s diameter in front of preopercular margin in two males 41-43 mm, almost to the same relative point in one male of 28 mm. Tongue moderately emarginate. Teeth in 3 or 4 irregular rows at symphysis, tapering to one or two rows on side; teeth in outer row in both jaws larger than posterior ones, those in outer row of upper jaw somewhat larger than corresponding teeth of lower jaw; a few inner- most teeth at symphysis of lower jaw subequal to those in outer row of upper jaw; no caninoids. No papillae or flaps on shoulder girdle. No sharp ridge or crest in front of dorsal. Isthmus rather broad, attachment of gill membrane nearly at lower angle of pectoral base. Scales large, about 32; none on antedorsal distance, side of head, base of pectoral, NO. 7 GINSBURG: NEW SPECIES OF GOBIOID FISHES 117 throat or ventral aspect of belly; scales on middle of body extending to within a short distance of base of pectoral; anterior boundary of scales marked by a line passing approximately from origin of first dorsal to upper angle of pectoral base; scales along middle part of body, pos- teriorly, ctenoid; anterior scales under base of second dorsal, and those near profiles, cycloid (most scales missing in specimens examined and description of squamation possibly subject to correction). First dorsal with 7 flexible spines (in all 4 specimens examined), rather high, but none notably filamentous, the fourth reaching base of second or third dorsal ray. Second dorsal rays usually 12 (in 3), sometimes 11 (in 1) ; anal rays 11 (in all 4) ; posterior dorsal rays extending a little beyond a vertical through end of hypural in 2 males 41-43 mm, those of anal just reaching that vertical or slightly beyond in the same two males; those of both fins just about reaching that vertical in a specimen 35 mm, and falling a little short in a male 28 mm. Pectoral rays 19 (in 1) or 20 (in 3), all connected by an interspinal membrane, the fin rather long, the longest rays reaching a vertical through base of third to fifth ray of second dorsal. Ventrals united, interspinal membrane rather well developed, its posterior margin with notably pronounced fimbriae; posterior end of fin reaching anus or falling a little short. Caudal rather long, equal to or a little less than half the standard length in the large males. Anal papillae of male rather short and pointed. A longitudinal, rather narrow, dark streak slightly below a median line, approximately from base of pectoral to under origin of second dorsal; a similar less well marked, interrupted and parallel streak a little above a median line; (a longitudinal series of four rather diffuse blotches on the 28 mm specimen, the first at posterior end of and con- fluent with lower dark streak, the last at base of caudal; only the last blotch perceptible in the larger specimens examined, but these specimens probably faded) ; two spots on base of caudal, one below the other, more or less confluent, and more or less also confluent with the last spot—in the longitudinal series of four spots—on the base of the caudal; a small oval spot on fleshy base of pectoral, a more diffuse, transverse, rather arched shaded area on fin, at its base; upper part of caudal with longitudinal rows of narrow elongate dark spots (in one specimen, the dark spots very intense, alternated with whitish spots, and with a whitish submarginal band; this pronounced development of color proba- bly showing a sexually ripe male), lower part dusky (dorsals and anal more or less injured and color cannot be described). 118 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 Measurements—Wwo males 41-43 mm. Caudal 46.5-50, ventral 29.5, pectoral 35-39.5, depth about 12.5 (cannot be measured accurately in these specimens), least depth of caudal peduncle 8.5-9, head 28-28.5, postorbital part of head 15.5, head depth directly behind eye 14-14.5, head width at same point 15-15.5, maxillary 21-22, snout 8, eye 7.5-8, antedorsal distance 35.5-37.5. Holotype—In Hancock Coll. La Paz Bay, Gulf of California; dredged in 7 fathoms, sandy mud; February 21, 1936; male 43 mm. Paratypes—Two obtained with the type, male 41 mm, specimen of 35 mm in bad condition. Also, Escondido Bay, Gulf of California, dredged in 20 fathoms; March 12, 1937; male 28 mm. Distinctive characters—This species is easily distinguished from all known gobies of the Pacific coast of North and South America by a combination of striking characters, especially, its long maxillary, the large scales and the medium count of dorsal and anal rays. Its relation- ship is discussed under the genus. Gobulus hancocki, new species Description—F¥orm very slender; body moderately compressed ; head notably depressed. Mouth rather small, terminal, moderately oblique, a horizontal through distal margin of upper lip passing ap- proximately through lower margin of eye; lower jaw slightly projecting. Maxillary rather short, its end falling under posterior margin of pupil. Eye rather small, interorbital wide. No ridge or crest in front of dorsal. Shoulder girdle without flaps or papillae. Isthmus restricted, attach- ment of branchiostegal membrane near lower angle of pectoral base. No scales anywhere. First dorsal with 7 flexible spines, none prolonged. Second dorsal and anal with 12 and 11 rays, respectively; tip of pos- terior dorsal rays ending at some distance from end of hypural. Pectoral short, with 16 rays, its end nearly attaining a vertical through base of sixth spine. Ventral short, failing to reach anus by a wide margin. Caudal rather short, somewhat pointed. Dorsal and ventral aspects rather light colored, lateral aspect for greater part of its extent notably darker; fins uniformly light, except caudal having a somewhat curved, broad, dark band not far from its base; no other spots or color marks anywhere. Measurements—Male 29 mm. Caudal 23.5, ventral 18, pectoral 18.5, depth 12.5, least depth of caudal peduncle 9, head 24.5, postorbital NO. 7 GINSBURG: NEW SPECIES OF GOBIOID FISHES 119 part of head 16, head depth 9.5, head width 11, maxillary 10, snout 6.5, eye 4.5, antedorsal distance 34.5. Holotype—In U.S. Nat. Mus. Secas Island, Panama; shore, coral tide flat; W. L. Schmitt; Feb. 6, 1935; the only specimen examined. Distinctive characters and relationship—This species is evidently near Gobulus crescentalis (Gilbert), the only known species of its genus, differing in its markedly more slender body, and in having the mid-ventral area light colored like the back—darker than the back in crescentalis. This species is named after Captain Hancock in recognition of his interest in the scientific exploration of Pacific waters. Lepidogobius seta, new species Diagnosis.—Scales cycloid, small, about 65; none on antedorsal dis- tance, side of head, base of pectoral or throat. Maxillary very long, nearly reaching margin of preopercle. No definite papillae on shoulder girdle. D.6 to 7-11 to 12; A. 9 to 10; none of the dorsal spines notably elongated. Pectoral rays 21. Tongue slightly emarginate. Teeth in a notably broad band. Skull with a rather narrow ridge over orbit; no other ridges in posterior orbital region of skull. Holotype—In U. S. Nat. Mus. Puerto Refugio, Angel de la Guarda Island, Gulf of California; Albatross; March 29, 1889; 58 mm in standard length, the caudal broken. Paratype—tIn U. S. Bur. Fish., obtained with the type, 64 mm. Relationship.—This species is nearest to Lepidogobius (Gillichthys) detrusus (Gilbert and Scofield), differing chiefly in having fewer anal rays, a less extensive squamation, a narrower supraorbital ridge, and in lacking a median occipital ridge on the skull. Lepidogobius luculentus, new species Diagnosis —Scales small, cycloid, embedded, very moderately over- lapping in large specimens; none on antedorsal distance, side of head, base of pectoral or throat. Maxillary rather short, ending approximately under posterior margin of pupil in large specimens. Shoulder girdle with flaps of moderate size, usually 2, sometimes 1 or 3. First dorsal nearly always with 5 spines, varying 3-6; the first spine more or less prolonged in some individuals, not prolonged in others (probably males and females, respectively). Second dorsal nearly always with 18 or 19 rays, infrequently 17; anal rays nearly always 16 or 17, infrequently 120 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 18; pectoral rays 23-26. Tongue bilobate. Supraorbital ridge expanded posteriorly. Holotype.—In Bingham Oceanog. Coll. Puerto Refugio, Angel de la Guarda Island, Gulf of California; 51 mm. Paratypes—In Bingham Oceanog. Coll. 47 specimens 35-53 mm taken together with the type. San Francisquito Bay, one specimen 33 mm. Distinctive characters and relationship—This species is nearest to Lepidogobius gilberti Eigenmann and Eigenmann and differs in having two instead of one papillae on the shoulder girdle, with very few excep- tions, and in the male having the first dorsal spine prolonged. It lacks the dark, obliquely elongate spot or blotch on the opercle which is char- acteristic of gilberti. ‘The color of this species, in general, is lighter than in any known species of Lepidogobius. Microgobius erectus, new species Diagnosis—Mouth nearly vertical, end of maxillary assuming a ventral position, a vertical tangent through posterior margin of max- illary passing approximately through anterior margin of eye. Teeth in two rows, notably small, no caninoids. Scales rather large, in 38 rows to base of caudal, cycloid; a small patch of weakly ctenoid scales on middle of body, under first dorsal; scales extending forward to a verti- cal through origin of first dorsal; none on antedorsal distance, side of head, base of pectoral or throat. A membranous ridge on midback, in front of first dorsal, rather well developed. D. 7-15; A. 15; the spines not especially prolonged. Pectoral rays 22-23, its tip reaching a vertical variably situated between bases of first to third dorsal rays. Ventral approximately reaching anal opening. Caudal comparatively rather long, about two-fifths the standard length. Body and head conspicuously compressed. Holotype—lIn Bingham Oceanog. Coll. Northern part of Gulf of California; 26 fathoms; female 82 mm. Paratypes—In Bingham Oceanog. Coll. obtained with the type; 2 females 56-58 mm, 4 males 56-66 mm, 1 small specimen 40 mm, sex not determinable by external examination. All specimens not in very good condition; the largest, a female, in somewhat better condition than others selected as the holotype, although the belly appears to be some- what abnormally distended. Distinctive characters and relationship.—This species differs mark- edly from all known species of Microgobius by its small teeth and No. 7 GINSBURG: NEW SPECIES OF GOBIOID FISHES 121 comparatively large scales. ‘The nearly vertical mouth is more extreme in its position than in any known species of its genus. In the position of the mouth it resembles most nearly Microgobius signatus Poey, and it has an antedorsal ridge like the older species. However, it has notably smaller teeth, larger scales, and fewer fin rays and it is evidently not closely related to signatus. Because erectus has some important char- acters more extremely developed than any of its congeners, and in general, because of the very distinctive combination of all characters, its precise affinities are not patent. REPORTS ON THE COLLECTIONS OBTAINED BY ALLAN HANCOCK PACIFIC EXPEDITIONS OF VELERO III OFF THE COAST OF MEXICO, CENTRAL AMERICA, SOUTH AMERICA, AND GALA- PAGOS ISLANDS IN 1932, IN 1933, IN 1934, IN 1935, IN 1936, IN 1937, AND IN 1938. LAND AND BRACKISH WATER MOLLUSCA OF ‘COCOS ISLAND By G. DALLAS HANNA and LEO GEORGE HERTLEIN Tue UNIVERSITY OF SOUTHERN CALIFORNIA PUBLICATIONS ALLAN HANCOCK PACIFIC EXPEDITIONS VOLUME 2, NUMBER 8 IssuED AUGUST, 1938 THE UNIVERSITY OF SOUTHERN CALIFORNIA PRESS Los ANGELES, CALIFORNIA LAND AND BRACKISH WATER MOLLUSCA OF COCOS ISLAND By pal G. Dattas HANNA and Lro GEORGE HERTLEIN 7, Le ~ % of * 4 California Academy of Sciences, San Francisco, California The collections upon which this paper is based were made by mem- bers of the Expedition of the California Academy of Sciences to the Galapagos Islands in 1905-1906;1 by the junior author during an expe- dition to the Galapagos Islands in Captain G. Allan Hancock’s motor cruiser, Velero III, in 1931-1932 ;2 and by members of the Templeton Crocker Expedition of the California Academy of Sciences in 1932.3 Cocos Island* lies in 5°32’57” N. Lat., 86°59/17” W. Long., about half way between the Galapagos Islands and the Central American coast. Politically, it belongs to Costa Rica. The island is about 500 kilometers from the mainland. It is composed, at least for the most part, of volcanic agglomerate and other volcanic rocks. ‘The circumfer- ence is about 23.3 kilometers (about 13 nautical miles or 14.6 land miles) and the area is approximately 46.6 square kilometers. The highest point of elevation is in the western part of the island and has been reported® to reach a height of 849.8 meters (2,788 feet). There is much rainfall and the largest stream, which flows into Wafer Bay, is in the Arroyo del Genio. The coast is abrupt at many places and there 1Slevin, J. R., Log of the Schooner Academy on a voyage of Scientific Research to the Galapagos Islands, 1905-1906. California Academy of Sciences, Occasional Paper 17, 1931, 162 pp., 17 pls. [General account. ] 2 For a general account of this Expedition see: Sam T. Clover, A Pioneer Heritage. Los Angeles, California, 1932. Saturday Night Publishing Co., pp. 1, II, 1-291. 97 pls. 4 maps. 1 text figure. See especially pp. 182-218 and map showing itinerary and route, inside front cover. 3 Grunsky, C. E. The Templeton Crocker Expedition of the California Academy of Sciences, 1932. Foreword, Proc. Calif. Acad. Sci., ser. 4, vol. 21, no. 1, March 14, 1933, pp. 1-2. Introductory statement by Templeton Crocker, pp. 3-9, pl. 1. ————— Hanna, G. D., Science, vol. 76, no. 1974, October 28, 1932, pp. 375-377. 4 See handbooks prepared under the direction of the Historical Section of the Foreign Office, London, vol. 22, no. 141, 1920, pp. 7-30. ————— Campbell, M. Searching for Treasure in Cocos Island. New York, 1932. Frederick A. Stokes Co., VIII, 279 pp., frontispiece colored, 4 pls. 5 South America Pilot, H. O. no. 174, Ed. 2, vol. 3, 1920, p. 405. Mexico and Central America Pilot (West Coast), H. O. no. 84, Ed. 7, 1928, p. 69. [ 123] 124 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 are numerous waterfalls. This beautiful and picturesque island, covered with dense tropical vegetation, has been the object of much interest due to the legends of treasure which is reported to have been hidden there by pirates. Schmidt® in his discussion of the zoogeography of Cocos Island con- cluded that the few native species of vertebrates, four land birds and two lizards, are mostly distinct from those of any other part of the world, but that they are allied to Central America, the nearest land mass. [The forms are such that transport or passage’ across the inter- vening ocean is understandable. He further stated: ‘“Che species have probably arisen in consequence of geographic isolation, without indica- tion of adaptive change or changes due to natural selection.” Papers on the marine mollusks have been published by von Martens,$ Pilsbry and Vanatta,® Biolley,1° Dall,!! Hertlein,!2 and Tomlin.12 The majority of the marine species from Cocos Island are the same as those found on the mainland of the adjoining coast. Pfeiffer,14 von Martens,!® Kobelt,!® Dall,17 Ancey,!8 Biolley,!® and Pilsbry2° have published information dealing with the land shells and 6 Schmidt, K. P., Essay on the Zoogeography of the Pacific Islands, in Shurcliff, S. N. Jungle Islands. Putnam Press, New York, 1930, pp. 278-280. See also Biolley, P., Mollusques de L’Isla del Coco. Mus. Nac. de Costa Rica, 1907, 30 pp. 2 maps. 7 For a general discussion of the faunas and floras of oceanic islands, see Gulick, A., Biological Peculiarities of Oceanic Islands. The Quarterly Review of Biology, vol. 7, no. 4, 1932, pp. 405-427. 8 yon Martens, C. E., Die Meeres-Conchylien der Cocos-Insel. Sitz. Ges. Naturf. Freunde zu Berlin, Jahrg. 1902, no. 6, pp. 137-141. 9 Pilsbry, H. A., and Vanatta, E. G., Proc. Washington Acad. Sci., vol. 4, 1902, p. 559. 10 Biolley, P., Mollusques de L’Isla del Coco. Mus. Nac. de Costa Rica, 1907, pp. 19-30. 11 Dall, W. H., Bull. Mus. Comp. Zool., vol. 43, no. 6, 1908, pp. 436-437; Proc. U. S. Nat. Mus., vol. 38, 1910, p. 225; Proc. U.S. Nat. Mus., vol. 51, 1917, p. 578. 12 Hertlein, L. G., Nautilus, vol 46, no. 2, 1932, pp. 44-45; Proc. Amer. Philos. Soc., vol. 78, no. 2, 1937, pp. 303-312, 1 pl. 13 A few species have been cited from Cocos Island by Tomlin, J. R. le B., in Jour. Conch., vol. 18, no. 6, 1927, pp. 153-170; no. 7, 1928, pp. 187-198. 14 Pfeiffer, L., Symb. ad Hist. Helic., sect. 3, 1846, p. 66. 15 yon Martens, E. C., Sitz. Ges. Naturf. Freunde zu Berlin, Jahrg. 1898, no. 9, pp. 156-160; Jahrg. 1902, no. 3, pp. 59-62. 16 Kobelt, W., Nach. Deutsch. Malak. Ges., Jahrg. 31, 1899, pp. 26-28. 17 Dall, W. H., Proc. Acad. Nat. Sci. Philadelphia, vol. 52, 1900, pp. 96-99. 18 Ancey, C. F., Journ. de Conchyl., vol. 51, no. 2, 1903, pp. 97-104. 19 Biolley, P., Mollusques de L’Isla del Coco. Mus. Nac. de Costa Rica, 1907, pp. 13-19. 20 Pilsbry, H. A., Manual Conch., ser. 2, vol. 18, 1907, pp. 325-330. NO. 8 HANNA AND HERTLEIN: MOLLUSCA 125 references to these works are found under various species in the follow- ing pages. After reducing some of the names to synonymy we are able to recog- nize only five definitely endemic species of land snails from the island. ‘Two others, an Opeas and a Leptinaria, may have been introduced. The endemic forms belong to the genera Ochrodermella, Nesopupa, Succinea, and Guppya. The representatives of all except the last have their closest relatives in Polynesia. All of the species are rather inconspicuous and this makes the anomaly in distribution the more difficult to explain. It hardly seems possible that collectors would have missed getting some representatives of the rich Central American or Galapagan faunas if they were present. Therefore we are forced to admit, for the present, the Polynesian affinities of the land shells. This conclusion is in agree- ment with the opinion expressed by Kobelt, who explained the Poly- nesian affinities of the land snails as being due to the eastward direction of the equatorial countercurrent which flows past Cocos Island. It should be mentioned that all of the species of land snails recorded herein have been secured on the lower levels of the island. It seems possible from conditions found elsewhere that there may be others at higher elevations. The four brackish water species listed herein, belonging to Auricula and Melampus, wide-ranging tropical genera, are of no great value in deciphering the origin of insular faunas. They have been determined as forms which also inhabit the adjacent coast of the mainland, some 500 kilometers to the east. Siphonaria gigas Sowerby and its variety characteristica Reeve, and Neritina pilsbryi Tryon (referred to as N. latissima var. globosa Broderip, by von Martens, and Biolley) occur at Cocos Island, but these have been placed with the marine mollusks in the faunal lists of Cocos Island. Ochrodermella cumingiana (Pfeiffer) Tornatellina cumingiana Pfeiffer, Proc. Zool. Soc., London, January- June, 1850, p. 134. “Real Llejos (H. Cuming)” [Nicaragua]. —Pfeiffer, Conchyl.-Cab., vol. 1, abt. 15, 1841-1855, Pupa, p. 148, pl. 18, figs. 6, 7—Pfeiffer, Monogr. Helic. Viv., vol. 3, 1$53,. pa 525: von Martens, Biol. Centrali-Americana, Moll., 1898, p. 324. von Martens, in Albers, Die Helic., ed. 2, 1860, p. 260. Kobelt, Nach. Deutsch. Malak. Ges., Jahrg. 31, 1899, p. 27. Cocos Island. 126 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 Leptinaria cumingiana (Pfeiffer), Clessen Ed., Nomen. Helic. Viv., 1878-1881, p. 336. Ochroderma cumingianum (Pfeiffer), Ancey, Journ. de Conchyl., vol. 51; no. Z,:1903, p. 102. ‘Cocos Island: Ochroderma cumingiana (Pfeiffer), Pilsbry, Man. Conch., ser. 2, vol. 18, 1907, p. 327, pl. 47, fig. 20. [Records repeated. ] Tornatellina pittieri von Martens, Sitz. Ges. Naturf. Freunde zu Ber- lin, Jahrg. 1898, no. 9, p. 157. “Cocos-Insel bei Costa Rica.” Kobelt, Nach. Deutsch. Malak. Ges., Jahrg. 31, 1899, p. 26. von Martens, Biol. Centrali-Americana, Moll., 1901, p. 640, pl. 44, fig. 10. von Martens, Sitz. Ges. Naturf. Freunde zu Berlin, Jahrg. 1902, no. 3, p. 60. Cocos Island. Biolley, Mollusques de L’Isla del Coco. Mus. Nac. de Costa Rica, 1907, p. 15. Cocos Island. Leptinaria (Neosubulina) pittieri (von Martens), Dall, Proc. Acad. Nat. Sci. Philadelphia, vol. 52, 1900, p. 96. Cocos Island. Ochroderma pittieri (von Martens), Pilsbry, Man. Conch., ser. 2, vol. 18, 1907, p.. 328, pl. 47, figs. 15, 16. Leptinaria (Neosubulina) martensi Dall, Proc. Acad. Nat. Sci. Phila- delphia, vol. 52, April 16, 1900, p. 97, pl. 8, fig. 10. “Cocos Island, under stones, Heller and Snodgrass.” Tornatellina martensi (Dall), von Martens, Biol. Centrali-Americana, Moll., 1901, p. 640. Type locality cited. Ochroderma martensi (Dall), Pilsbry, Man. Conch., ser. 2, vol. 18 1907, p. 329, pl. 47, figs. 22, 23, 24. Cocos Island. [Previous records cited and new sect. Ochrodermella formed with mar- tensi as type. | Ancey, Journ. de Conchyl., vol. 51, no. 2, 1903, p. 102. Cocos Island. Many specimens of Ochrodermella are in the collection from Cocos Island. Those obtained by the Hancock Expedition were found among leaves and mosses along the creeks draining into Wafer and Chatham bays. Only sinistral shells were taken at the first locality and only dextral ones at the last, but except for being reversed the specimens seem indistinguishable. The description and figures of cumingiana fit dextral shells from Cocos Island almost exactly; it is therefore practi- cally certain that Cuming’s Nicaragua locality record was an error. i ) } | No. 8 HANNA AND HERTLEIN : MOLLUSCA 127 This seems more plausible when it is noted that Pfeiffer had already described Helix pacifica from Cocos Island when he described cumin- giana. O. martensi has nothing we can find to distinguish it from cumin- giana, and pittieri is an exact sinistral counterpart. Apparently the last is the dominant form and the identity has been recognized by von Martens (1902, p. 60), Dall (letter May 24, 1902, quoted by Biolley), and Biolley (1907, p. 15). Pilsbry segregated the Cocos Island species under a new section, Ochrodermella. ‘The type of Ochroderma is gigas, a very much larger and heavier shell from the Caroline Islands. As genera are now consti- tuted, it seems rather difficult to reconcile the union so we have given the section generic standing. Ochrodermella biolleyi (von Martens) Text figure 1 Tornatellina biolleyi von Martens, Sitz. Ges. Naturf. Freunde zu Ber- lin, Jahrg. 1902, no. 3, p. 60. ‘‘Cocos-Island.” Biolley, Mollusques de L’Isla del Coco. Mus. Nac. de Costa Rica, 1907, p. 16. Cocos Island. Tornatellina hopkinsi Sykes, Zool. Record, vol. 39, for 1902 [Issued 1903], Moll. p. 45. Costa Rica [Nomen nudum. See Biolley, 1907, p. 16, footnote 2.] Fic. 1. Ochrodermella biolleyi (von Martens). Length, 13 mm. 128 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 Shell much longer than O. cumingiana but with about the same coloration, olive brown, glossy, streaked with narrow axial lines of burnt umber; apex flatly obtuse, minutely and irregularly wrinkled; whorls seven with suture slightly impressed; aperture entirely without teeth or plications of any kind; outer margin thin, without callus; columella, slightly twisted; base imperforate. Length, 13 mm., diameter, 4 mm. Hypotype, no. 524 (Calif. Acad. Sci. type coll.) from Cocos Island collected by W. H. Oschner, a member of the Expedition of the Cali- fornia Academy of Sciences to the Galapagos Islands in 1905-1906. The specimen figured is the largest available specimen in our col- lection and is 2%4 mm. longer than von Martens’ type. Our other two measure 9.5 and 10 mm. in length. These specimens were found among a large series of O. cumingiana which passed through Dall’s hands without detection. The nuclear whorls appear to be identical with cumingiana and the chief distinguishing features are the greater length and the lack of pli- cations in the aperture. Although the species has not been illustrated heretofore, von Martens’ description seems to fit our shells so exactly that we have confidence in the correctness of the identification. Leptinaria biolleyi von Martens Leptinaria biolleyi von Martens, Biol. Centrali-Americana, Moll., June, 1898, p. 319, pl. 18, fig. 14. “Central Costa Rica: en- virons of San José, 1135 metres above the sea, among moss (Biolley).” “E. Costa Rica: Talamanca (Pittier, March, 1395). von Martens, Sitz. Ges. Naturf. Freunde zu Ber- lin, Jahrg. 1902, no. 3, p. 61. ‘‘in der Nahe von Wohnungen an der Bucht von Wafer, und nicht zahlreich.” Biolley, Mol- lusques de L’Isla del Coco. Mus. Nac. de Costa Rica, 1907, p. 16. Wafer Bay, Cocos Island. Pilsbry, Manual Conch., ser. 2, vol. 18, 1907, p. 316, pl. 41, fig. 18. Cocos Island. This species was described from Costa Rica by von Martens. Its presence on Cocos Island (not numerous and found in the vicinity of the habitation at Wafer Bay) led von Martens to suspect that the species may have been recently introduced on the island on vegetation or by some other method. No. 8 HANNA AND HERTLEIN : MOLLUSCA 129 Nesopupa cocosensis (Dall) Vertigo cocosensis Dall, Proc. Acad. Nat. Sci. Philadelphia, vol. 52, April 16, 1900, p. 98, pl. 8, fig. 13. “Cocos Island, on leaves, Heller and Snodgrass.” Ancey, Journ. de Conchyl., vol. 51, no. 2, 1903, p. 103. Cocos Island. Biolley, Mollusques de L’Isla del Coco. Mus. Nac. de Costa Rica, 1907, p. 17. Chatham Bay, Cocos Island. Pupa cocosensis (Dall), von Martens, Biol. Centrali-Americana, Moll., 1901, p. 640. Type locality cited. Vertigo cocoénsis Dall, von Martens, Sitz. Naturf. Freunde zu Berlin, Jahrg. 1902, no. 3, p. 61. Chatham Bay, Cocos Island. Nesopupa cocosensis (Dall), Pilsbry, Man. Conch., ser. 2, vol. 25, April, 1920, p. 232, pl. 30, figs. 10, 11. [Former records cited and much information given as to the relationship of this Poly- nesian group; a new section, Cocopupa Pilsbry and Cooke, is made for the species. | About 40 specimens of this species were found by L. G. Hertlein and J. T. Howell on leaves and mosses a short distance up the creek which drains into Wafer Bay, near the house erected by Gissler. An additional one was taken in a similar situation at Chatham Bay. Succinea globispira von Martens Succinea globispira von Martens, Sitz. Ges. Naturf. Freunde zu Berlin, Jahrg. 1898, no. 9, p. 158. Cocos Island. ——- Kobelt, Nach. Deutsch. Malak. Ges., Jahrg. 31, 1899, p. 26. von Mar- tens, Biol. Centrali-Americana, Moll., 1901, p. 641, pl. 44, fig. 12. Dall, Proc. Acad. Nat. Sci. Philadelphia, vol. 52, 1900, p. 99. “Cocos Island, on leaves, Heller and Snodgrass.” Biolley, Mollusques de L’Isla del Coco. Mus. Nac. de Costa Rica, 1907, p. 17. Cocos Island. ? Succinea dalli Biolley, Mollusques de L’Isla del Coco. Mus. Nac. de Costa Rica, 1907, p. 18. Cocos Island. Seven specimens of Succinea globispira were collected on Cocos Island along the banks of the creek which empties into Wafer Bay. The thin shell, low spire, and very large, sloping body whorl seem to be the chief distinguishing features. Von Martens pointed out that the 130 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 species is “Aehnlich S. crocata A. Gould von den Samoa-Inseln und modesta A. Gould von den Samoa-und Tonga-Inseln, aber etwas schmaler und das Gewinde noch stumpfer, knopfformig.” One of the specimens of Succinea submitted to Dall by Biolley was stated to have ‘“‘‘a more depressed spire, much lighter color, smaller coil, proportionately wider aperture, and the surface quite regularly, minutely ribbed.’”’ Biolley listed this form as Succinea sp., but stated that if it is found to be new in the future, he would propose the name Succinea dalli. In view of the variability of members of this genus, we hesitate to recognize the species on the evidence available. Opeas gracile (Hutton) Bulimus gracile Hutton, Jour. Asiatic Soc. Bengal, vol. 3, 1834, pp. 84, 93. Bulimus junceus Gould, Proc. Boston Soc. Nat. Hist., vol. 2, Dec. 1846, p. 191. “Hab. Society and Sandwich Islands.”” —— USS. Explor. Exped., vol. 12, 1852, p. 76, Atlas, Moll. & Shells, 1856, pl. 6, figs. 87, 87a. “Inhabits Tahiti and Eimeo.” Opeas junceum (Gould), von Martens, Sitz. Ges. Naturf. Freunde zu Berlin, Jahrg. 1898, no. 9, p. 156. Cocos Island. Kobelt, Nach. Deutsch. Malak. Ges., Jahrg. 31, 1899, p. 26. von Martens, Sitz. Ges. Naturf. Freunde zu Berlin, Jahrg. 1902, no: 3, ‘ps 6. Ancey, Journ. de Conchyl., vol. 51, no. 2, 1903, p. 102. Cocos Island. Also Polynesia. Biolley, Mol- lusques de L’Isla del Coco. Mus. Nac. de Costa Rica. 1907, p. 17. Wafer Bay, Cocos Island. Opeas juncea (Gould), Dall, Proc. Acad. Nat. Sci. Philadelphia, vol. 52, 1900, p. 96. Cocos Island. Opeas gracile (Hutton), Pilsbry, Man. Conch., ser. 2, vol. 18, 1906, pp. 125-132, 188, 198-200, pl. 18, figs: 3-6; pl. 22) fig. @; pl. 28, figs. 70, 71. “India, type locality.’”’ Generally distributed throughout the tropics including America. Von Martens first listed O. junceum (Gould) from Cocos Island and was followed by Dall and Ancey. Pilsbry (1906, p. 131) has shown that the name “was based upon the small Polynesian race of gracile.” He also reduced many other names to synonomy and showed 1 No. 8 HANNA AND HERTLEIN: MOLLUSCA 131 that this tropical species has probably the widest geographic range of any land snail. We have two specimens from Cocos Island, one taken by the Hancock Expedition along the creek draining into Wafer Bay and the other by the Expedition of the California Academy of Sciences in 1906 without restricted locality. It must be abundant at favorable places on the Galapagos Islands because the 1906 Expedition obtained a very large series on Charles Island. According to von Martens (1902, p. 61) this species was found by Biolley only at Wafer Bay near the settlement where it occurred upon palm leaves and banana leaves, and may have been recently introduced on the Island. Guppya pacifica (Pfeiffer) Helix pacifica Pfeiffer, Symb. ad Hist. Helic., sect. 3, 1846, p. 66. Cocos Island. ——— Pfeiffer in Martini and Chemnitz, Conch.- Cab., Ed. 2, vol. 1, abt. 12, Helix, no. 549, pl. 88, figs. 3-5. Cocos Island. Pfeiffer, Monogr. Helic. Viv., vol. 1, 1847, p. 52. Cocos Island. Reeve, Conch. Icon., vol. 7, Helix, 1852, pl. 112, fig. 640. Cocos Island. Tryon, Manual Conch., ser. 2, vol. 3, 1887, p. 78, pl. 14, fig. 28. Cocos Island. Nanina (Nigritella) pacifica (Pfeiffer), Clessin Ed., Nom. Helic. Viv., 1878-1881, p. 80. Cocos Island. Guppya pacifica (Pfeiffer), Ancey, Journ. de Conchyl., vol. 51, no. 2, 1903, p. 101. Cocos Island. —— Biolley, Mollusques de L’Isla del Coco. Mus. Nac. de Costa Rica, 1907, p. 14. Cocos Island. Conulus sp., von Martens, Sitz. Ges. Naturf. Freunde zu Berlin, Jahrg. 1898, no. 9, p. 156. Cocos-Insel. —— Dall, Proc. Acad. Nat. Sci. Philadelphia, vol. 52, 1900, p. 96. Guppya pacifica var. conulus von Martens, Sitz. Ges. Naturf. Freunde zu Berlin, Jahrg. 1902, no. 3, p. 59. Cocos Island. Guppya hopkinsii Dall, Proc. Acad. Nat. Sci. Philadelphia, vol. 52, April 16, 1900, p. 97, pl. 8, figs. 5 and 6; Pilsbry, p. 105, 4 text figs. “Cocos Island, on leaves, Heller and Snodgrass.” Guppya hopkinsi Dall, von Martens, Biol. Centrali-Americana, Moll., 1901, p. 620. Cocos Island. 132 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 Guppya fultoni Gude, Proc. Malacol. Soc. London, vol. 5, no. 4, April, 1903, p. 265, pl. 7, figs. 18, 19, 20. “Cocos Island, Pacific Ocean.” Biolley, Mollusques de L’Isla del Coco. Mus. Nac. de Costa Rica, 1907, p. 14. Cocos Island. Pfeiffer’s description of pacifica fits almost exactly the large series of shells which we have available. The same is true of the figure repro- duced by Tryon. One of our sets was collected by the 1905-1906 Expe- dition of the Academy (19 specimens); these passed through Dall’s hands and were identified as Guppya hopkinsi by him. They may there- fore be considered as authentic. In all of the specimens there is a definite tendency toward angulation of the body whorl at the periphery, a fea- ture not shown in Dall’s drawings, which may have been made from a senile specimen. Numerous specimens were taken by Hertlein and Howell of the Hancock and Templeton Crocker Expeditions, respec- tively, on leaves and mosses along the creeks draining into Wafer and Chatham bays. According to a note by Dall (published by Biolley, 1907, p. 15) he agreed with von Martens that the keeled and smooth forms are not more than varietally distinct. Under the circumstances and in view of insular conditions in general, we do not believe that there are sufficient differences in the series of available Guppya from Cocos Island to war- rant the recognition of more than one name. Auricula stagnalis d’Orbigny Auricula stagnalis d’Orbigny, Mag. de Zool. .... 183551923. d’Orbigny, Voy. Amér. Mérid., Moll., vol. 5, 1837, p. 325, pl. 42, figs. 7 and 8. Guayaquil, Ecuador. Reeve, Conch. Icon., vol. 20, 1878 (on title page), Auricula, sp. 3, pl. 2, fig. 3. “Hab. S. America.” Dall, Proc. Acad. Nat. Sci. Philadelphia, vol. 48, 1896, p. 452. Earlier records cited. von Martens, Sitz. Ges. Naturf. Freunde zu Berlin, Jahrg. 1902, no. 3, p. 62. Cocos Island. Biolley, Mollusques de L’Isla del Coco. Mus. Nac. de Costa Rica, 1907, p. 19 (as Auricula (?) stag- nalis Orb.) “En colonies nombreuses contre troncs d’arbres morts a demi submergés dans le lit de l’Arroyo del Genio, a peu de distance de son embouchure dans le Baie de Wafer.” Dall and Ochsner, Proc. Calif. Acad. Sci., ser. 4, vol. 17, no. 5, 1928, p. 178. Galapagos Islands, various localities. No. 8 HANNA AND HERTLEIN : MOLLUSCA 133 Nine living specimens of A4uricula were collected by Hertlein of the Hancock Expedition from beneath the bark of a fallen palm tree near the creek in Arroyo del Genio, which drains into Wafer Bay. They were found about 50 meters above the outlet of the creek. The water was apparently entirely fresh, at least during the ebb tide. The shells are uniform in size, about one half as long as those from the Galapagos Islands and the spire is much shorter. The series of spiral markings just below the suture is much stronger than in the specimens of stag- nalis which we have examined. ‘The shape is very similar to the species pellucens from Florida and the West Indies and if it were not for the known great variation of stagnalis we would not hesitate to identify the Cocos Island shells with the east coast species. Melampus panamensis (C. B. Adams) Auricula panamensis C. B. Adams, Ann. Lyceum Nat. Hist. New York, vol. 5, July, 1852, pp. 433, 542. “Panama and Taboga. 600 spec.’”” ——— Reeve, Conch. Icon., vol. 20, 1878, Auricula, sp. 59, pl. 7, fig. 59. “Hab. Jamaica.” Melampus panamensis (C. B. Adams), Pfeiffer, Monogr. Auric. Viv., 1856, p. 48. Dall, Proc. Acad. Nat. Sci. Philadelphia, vol. 52, 1900, p. 97. Cocos Island. von Martens, Biol. Cen- trali-Americana, Moll., 1900, p. 561, pl. 43, figs. 10, 10a. Previ- ous records cited. Dall, Bull. Mus. Comp. Zool., vol. 43, no. 6, 1908, p. 436. Cocos Island. Tralia panamensis (C. B. Adams), Dall, Proc. Acad. Nat. Sci. Phila- delphia, vol. 48, 1896, p. 452. Cocos Island. This species is not represented in our collections from Cocos Island. It is a slender shell with a high, sharply pointed spire, apparently one of the most distinct of this genus on the west coast. The color is dark reddish brown and the spire has a few faint spiral striations. For diag- nostic characters, reliance must be placed almost entirely upon Adams’ description and von Martens’ excellent figure. Its presence on Cocos Island rests upon the authority of Dr. Dall. Melampus tabogensis (C. B. Adams) Auricula tabogensis C. B. Adams, Ann. Lyceum Nat. Hist. New York, vol. 5, July, 1852, pp. 435, 542. ‘““Taboga and Panama. 800 134 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 spec.” Reeve, Conch. Icon., vol. 20, 1878 (on title page), Auricula, sp. 47, pl. 6, fig. 47. “Hab. Jamaica.” Melampus tabogensis (C. B. Adams), Pfeiffer, Monogr. Auric. Viv., 1856, p. 47. von Martens, Biol. Centrali-Americana, Moll., 1900, p. 560, pl. 43, fig. 8. Panama. von Martens, Sitz. Ges. Naturf. Freunde zu Berlin, Jahrg., 1902, no. 6, p. 137. Cocos Island. Biolley, Mollusques de L’Isla del Coco. Mus. Nac. de Costa Rica, 1907, p. 24. “Est abondant sur les plages sablonneuses de la Baie de Wafer et a l’embouchure de l’Arroyo del Genio.”’ The members of the 1905-1906 Expedition (Calif. Acad. Sci.) ob- tained about 100 specimens of this dark reddish brown species. It is a much heavier and slightly larger species than ¢rilineatus and is usually more highly polished. The columella usually bears not more than three teeth, the lowermost of which is very thick and ‘heavy. Melampus trilineatus (C. B. Adams) Auricula trilineata C. B. Adams, Ann. Lyc. Nat. Hist. New York, vol. 5, July, 1852, pp. 436, 543. “Panama, 1 spec.” Carpenter, Rept. British Assoc. Adv. Sci. for 1856 (issued 1857), p. 275. Melampus trilineatus (C. B. Adams), Pfeiffer, Monog. Auric. Viv., 1856, p. 44. von Martens, Biol. Centrali-Americana, Moll., 1900, p. 559, pl. 43, fig. 7. Panama. The members of the California Academy of Sciences Expedition of 1905-1906 secured a number of specimens of this species estimated at 5,000. All of these are rather smaller than the dimensions which Adams gave for his single specimen but they do not differ greatly from the one figured by von Martens. Naturally very great variation is displayed in so large a series. Light color bands vary from none to as many as five; there are usually four or five teeth on the columella, the lowermost one being the largest. One of the most constant characters in the lot is the presence of a series of spiral threads on the spire above the periphery. ‘These are not present on the dark reddish brown species which we refer herein to tabogensis, and do not seem to be present on a spirally banded beach-worn shell from Panama which Mr. A. M. Strong has identified for us as ¢rilineatus. A considerable number of the Cocos No. 8 HANNA AND HERTLEIN : MOLLUSCA 135 Island shells have a series of longitudinal, light-yellowish stripes, similar to those described and illustrated by von Martens on the species which he named strigosus,2! the arrangement of the teeth on the columella, however, differs greatly from that species. 21 von Martens, C. E., Biol. Centrali-Americana, Moll., 1900, p. 560, pl. 43, fig. 9. “W. Costa Rica; in a small tributary of the Rio Boto, Golfo Dulce, on dead leaves (Pittier, March 1896).” REPORTS ON THE COLLECTIONS OBTAINED BY ALLAN HANCOCK PACIFIC EXPEDITIONS OF VELERO III OFF THE COAST OF MEXICO, CENTRAL AMERICA, SOUTH AMERICA, AND GALA- PAGOS ISLANDS IN 1932, IN 1933, IN 1934, IN 1935, IN 1936, IN 1937, AND IN 1938. NEMATODE PARASITES OF THE GALAPAGOS LAND IGUANA By ASHTON C. CUCKLER THE UNIVERSITY OF SOUTHERN CALIFORNIA PUBLICATIONS ALLAN Hancock Paciric EXPEDITIONS VOLUME 2, NUMBER 9 IssuED NOVEMBER 10, 1938 THE UNIVERSITY OF SOUTHERN CALIFORNIA PRESS Los ANGELES, CALIFORNIA NEMATODE PARASITES OF THE GALAPAGOS LAND IGUANA* (WitH THREE PLATES) ASHTON C. CUCKLER University of Nebraska The nematode parasites which are the basis of this study were col- lected by Dr. H. W. Manter from the intestine of the Galapagos land iguana, Conolophus subcristatus Gray, during the 1934 Allan Hancock Pacific Expedition. All parasites were from a single host taken on South Seymour Island, Galapagos. The writer wishes to express his indebtedness to Dr. Manter for the opportunity to study this material and for aid and advice during the work. The parasites had been fixed in hot 70 per cent alcohol. They were cleared with glycerine and mounted in this fluid for study. The prepa- ration and examination of the en face views of the lips were by the method suggested by Chitwood and Wehr (1935). The nematodes occurred in very large numbers in the intestine of the iguana. Nearly 4,000 specimens were collected and these repre- sented but a small part of the entire infection of a single host. It was found that five species of nematodes, all of the family Oxyuridae, subfamily Syphactinae, were represented in this single col- lection. All of these 5 species are considered to be new. They can be referred to two genera, one of which is described as new. Five genera of Syphaciinae occur in reptiles. Two of these, Alaeuris Thapar, 1925 and Thaparia Ortlepp, 1933, are characterized in part by the presence of caudal alae in the males, which is also a characteristic of the species from the Galapagos land iguana. These species further resemble Thaparia in the absence of lateral alae, the presence of two uteri and two ovaries, usually four genital papillae, and a single spicule and an accessory piece. However, the short esophagus of three regions, * Studies from the Zoological Laboratories, University of Nebraska, No. 199. [137] 138 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 the position of the vulva near the anus, and the length of the spicule in Thaparia seem sufficient to exclude the Galapagos species from this genus. The genus Alaeuris is characterized by Thapar (1925) as follows: “Oxyurids of small or medium size; simple lips; both lateral and caudal alae present, the latter very prominent; vulva behind the middle of the body; ovejector present terminating in a bulb; uteri two; spicule single; accessory piece present; only pre-anal papillae pedunculated, others sessile.” Four of the five species of nematodes from the Galapagos land iguana are apparently of the genus Alaeuris. These four species agree with the generic diagnosis as given by Thapar except for one character- istic, namely, the lateral alae do not seem to be present. However, Sand- ground (1929) has assigned to this genus a species, 4. hirsutus Sand- ground, 1929 (from a Central American iguana, Iguana rhinolopha), which apparently does not have lateral alae. The type species of 4laeuris, A. alaeuris Thapar, 1925, has lateral alae only at the posterior end of the male. The second species, 4. iguanae Thapar, 1925, apparently possesses lateral alae, but no mention is made of them in the specific diagnosis, and no figures show them. Until 1933, then, only one of the three species of Alaeuris has well- defined lateral alae, one is doubtful, and the third apparently lacks them. A nematode from Testudo verreauxi of South Africa was assigned to the genus Alaeuris by Ortlepp in 1933. This species, 4. conspicua Ort- lepp, 1933, possesses well-developed lateral alae in both sexes. The species from the Galapagos land iguana are like 4. hirsutus in respect to the absence of lateral alae. Since this is the only important character- istic in which the Galapagos forms differ from the diagnosis of Alaeuris, and it is evident that there are various degrees of development of this characteristic within the known members of the genus, this characteristic does not seem to be of sufficient importance to exclude the four Gala- pagos species from the genus Alaeuris. Consequently, four of the five species of nematodes from the Galapagos land iguana are assigned to the genus Alaeuris Thapar, 1925. The fifth species in the collection is con- sidered to represent a new, but rather closely related genus. Its relation- ship will be pointed out with its description. ‘Type specimens are deposited in the United States National Museum and in the Allan Hancock Foundation at The University of Southern California. No.9 CUCKLER: NEMATODE PARASITES 139 Alaeuris galapagensis, new species (Plate 13, figs. 1-7) This species was the most abundant in the collection. An identifica- tion and count of the entire collection revealed 668 males and 2,045 females of this species. These are medium-sized oxyurids with slender, spindle-shaped bodies. The anterior end is truncated, but the posterior end of the female is extended as a long, straight, pointed tail. The male tail is short and rounded. The females (fig. 1) range from 4.52 mm. to 6.49 mm. in length by 0.39 mm. to 0.48 mm. in width. The length of the male (fig. 2) ranges from 2.75 mm. to 3.80 mm. and the width from 0.20 mm. to 0.30 mm. The body is covered with a clear, thin cuticula, which has indistinct transverse striations about 0.005 mm. apart. There are no cervical or lateral cuticular alae in either sex. The males have well-developed caudal alae. The cephalic region is distinct and truncate terminally (fig. 3). The terminal, triangular-shaped mouth (fig. 4) is formed by three simple lips which are distinctly separated from one another by small grooves. The dorsal lip is slightly taller than the ventrolateral lips. There are ten cephalic papillae and two amphids. The papillae are arranged in two circles. In the external circle are four papillae, two of which are situated near the posterior margin of each of the ventrolateral lips. There are no corresponding papillae on the dorsal lip. In the internal circle there are six papillae (fig. 4) ; two papillae are near the anterior margin of each of the lips. The amphids terminate slightly pos- terior to the level of the internal circle of papillae. ‘Two uncertain papilla-like structures could usually be seen in the en face view of the lips but could not be distinguished in the lateral or dorsal views of the cephalic region. The lips bound a triangular-shaped mouth. The buccal cavity, about 0.025 mm. in depth, has six toothlike projections extending into it from the esophageal wall. Three of the projections are continuous with the external surface of the esophagus, and three smaller, sharp projections arise from the inner surface of the esophagus. A small projection is found on the median anterior margin of the dorsal lip; no similar struc- tures were observed on the other lips. The conspicuous nerve ring encircles the anterior end of the esopha- 140 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 gus about 0.22 mm. in the male and 0.26 mm. in the female from the anterior end of the body. The excretory pore is ventral and prebulbar in both sexes. In the male it ranges from 0.96 to 1.45 (average 1.03) mm. and in the female from 1.38 to 1.99 (average 1.63) mm. from the anterior end of the body. The excretory pore is minute; it communicates with an oval- shaped vesicle into which the excretory canals enter. The vesicle is about 0.09 mm. in the male and 0.14 mm. in the female in length. There are four excretory canals which emerge from the lateral line areas in such a manner as to form an “‘X”’ with the vesicle at the junction. The posterior canals are wider than the anterior. The esophagus is of the usual oxyurid type. It is of the same muscu- lar structure throughout its length, except for the anterior cuticularized end which projects into the buccal cavity. There is a slight bulge in the esophagus about 0.05 mm. from its anterior end; from this point the width remains the same, 0.043 mm. in the female and 0.036 mm. in the male, to the slight constriction which marks the junction between the esophagus and the esophageal bulb. The bulb averages 0.165 mm. in the female and 0.125 mm. in the male in diameter. It contains a valvu- lar apparatus, consisting in part of three cuticularized blade-like struc- tures. The length of the esophagus, bulb included, ranges from 1.66 to 2.08 (average 1.84) mm. in the female and from 1.02 to 1.70 (average 1.43) mm. in the male. Thus it is.nearly one half the body length of the male and one third the body length of the female. Anteriorly the intestine is enlarged to a diameter greater than that of the esophageal bulb. The diameter of the flask-shaped enlargement is about 0.254 mm. in the female and 0.153 mm. in the male. From this maximum size the diameter of the intestine gradually decreases to ap- proximately 0.10 mm. in the female, slightly less in the male, which is the size maintained throughout the remainder of its length. Male: The male reproductive system is composed of a single, coiled testis which has a diameter of about 0.036 mm. The testis extends an- teriorly to about the level of the intestinal bulb. An expanded region of the testis connects with the seminal vesicle through an attenuated neck- like portion. The seminal vesicle is about 0.40 mm. in length and has a maximum diameter of 0.095 mm. The accessory reproductive structures (figs. 5 and 6) consist of the spicule, accessory piece, and the genital papillae. There is a single spicule, which ranges from 0.415 to 0.589 (average 0.496) mm. in length. The NO. 9 CUCKLER: NEMATODE PARASITES 141 proximal end of the spicule is slightly expanded at the point of attach- ment of the spicular muscles. The spicule width at this point is about 6.042 mm.; from this region the spicule gradually tapers to end in a fine sharp point. The accessory piece is well developed, V-shaped, and has a maximum width of 0.046 mm. and a length of about 0.076 mm. Posteriorly it tapers to a bluntly rounded, ventrally directed, hooked tip. There are four pairs of genital papillae located at the ventral body cleft (fig. 6). Three pairs are circumcloacal and one pair is caudal in position. Iwo of the pairs of circumcloacal papillae are precloacal in position. The most anterior and ventral pair of this group is well de- veloped and situated on projections from the body. These papillae, as well as the second pair of precloacal papillae, are considered to be sessile. The second pair of precloacal papillae can not be seen in the ventral view of the caudal region because they are small and dorsal to the large precloacal pair. The third pair of circumcloacal papillae is pedunculated and is adcloacal in position. These papillae are situated on stalks which extend nearly to the posterior extremity of the accessory piece. The fourth or caudal pair of papillae arises from the caudal stalk at about the junction of its fourth and last fifths. These papillae are well de- veloped and pedunculated. Summarizing, there are two pairs of pre- cloacal sessile papillae, one pair of adcloacal pedunculated papillae, and one pair of pedunculated caudal papillae. The caudal alae are wide and deep, and extend from the base of the tail to the base of the caudal papillae. The deepest point of the ala is at about its mid-region, where it extends ventrally to the level of the ventral precloacal papillae. The alae extend laterally to about the body width at the anterior end of the tail, but taper slightly at their posterior limits. Female: ‘The vulva is situated posterior to the middle of the body; it ranges from 2.6 to 3.4 (average 2.9) mm. from the anterior end. In the mature animals the vulva is surrounded anteriorly by a promi- nent cuticular expansion. The vagina is a well-developed muscular or- gan, which meets the body wall at an oblique angle. A common uterine stem connects the divergent uteri to the ovejector and vagina. The va- gina varies in length from 0.49 to 0.56 mm., and its width is about 0.08 mm. Between the vagina and the common stem of the uteri there is a less muscular structure, the ovejector. This structure is about 0.20 mm. in length by 0.07 mm. in width. At both ends it is equipped with valvu- lar, bulblike structures. 142 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 The uteri are divergent. The ovaries are large and club-shaped in the adult. Their average diameter is 0.070 mm. ‘The eggs are segmented in utero and the uteri may contain many or few eggs, depending upon the degree of maturity. The eggs (fig. 7) are large, with thin clear shells, ellipsoidal, and with an asymmetrically flattened surface on one side. The eggs range from 0.182 to 0.210 mm. in length by 0.077 to 0.098 mm. in width. The average size is 0.192 mm. by 0.089 mm. SPECIFIC DIAGNOSIS OF ALAEURIS GALAPAGENSIS Principal characters of genus. Oxyurids of medium size; males from 2.75 to 3.80 mm. by 0.20 to 0.30 mm.; females from 4.52 to 6.49 mm. by 0.39 to 0.47 mm. Thin cuticula, striations 0.005 mm. apart. No cervical or lateral alae; caudal alae in male. Cephalic region distinct and truncate; mouth surrounded by three simple lips. “Ten cephalic papillae and two amphids present; papillae in two circles; ventrolateral lips each with four papillae and an amphid; dorsal lip with two papillae, and a median anterior toothlike projection. Buccal cavity present con- taining six toothlike projections from anterior end of esophagus. Nerve ring about 0.22 mm. in male and 0.26 mm. in female from anterior end. Excretory pore prebulbar, about 1.03 mm. in male and 1.69 mm. in female from anterior end. Esophagus long and slender, about one half body length in male and one third body length in female. Intestine rectilinear, enlarged anteriorly into a bulb. Male: Bluntly rounded tail, 0.11 mm. long; wide caudal alae from base to distal fourth of tail. Spicule from 0.415 to 0.589 mm. in length, sharply pointed. Accessory piece well developed, 0.046 mm. by 0.076 mm. Four pairs of genital papillae; three pairs circumcloacal, of which two pairs are sessile, one pair pedunculated; one pair pedunculated caudal papillae at point alae join tail. Female: Straight pointed tail 0.57 mm. long. Vulva posterior to mid-body, 2.97 mm. from anterior end. Vagina very muscular, ovejector less muscular, connected to divergent uteri by a common uterine stem. Short oviducts connect large club-shaped ovaries to uteri. Eggs large, ellipsoidal, flattened on one side; measure 0.192 mm. by 0.089 mm.; segmented in utero. This species is named for its geographic location, the Galapagos Islands. NO. 9 CUCKLER: NEMATODE PARASITES 143 Affinities: This species conforms to Thapar’s diagnosis of the genus Alaeuris except that no lateral alae are present, and there is a difference in the character and disposition of the genital papillae. This species may be distinguished from 4. alaeuris on the basis of the prebulbar excretory pore, the number of cephalic papillae, the pe- dunculated adcloacal papillae, and the difference in the length of the spicule and accessory piece. The characters which distinguish this species from 4. iguanae are: its larger size, the distinct cephalic region, the distinct lips, the presence of a common uterine stem, unstriated caudal alae, the character of the genital papillae, and the longer spicule and accessory piece. This species may be distinguished from 4. hirsutus by its smaller size, longer relative length of esophagus, shorter spicule, longer accessory piece, difference in number of cephalic papillae, the character of the genital papillae, and the male tail which extends posterior to the border of the caudal alae. The following characters distinguish this species from A. conspicua: the absence of lateral alae, the size and shape of the spicule, the pre- bulbar position of the excretory pore, the absence of a spike on the nale tail, and the character and number of genital papillae. Alaeuris longispicula, new species (Plates 13 & 14, figs. 8-14) This species was less numerous in the collection than 4. galapa- gensis. Approximately 8 per cent of the specimens from the heavily infected host are of this species. These are medium-sized oxyurids with relatively slender bodies. The length of the male (fig. 12) is from 3.01 to 4.27 (average 3.58) mm., and the greatest body width is from 0.25 to 0.32 mm. The body grad- ually tapers from about mid-body to the extremities. The females (fig. 8) range in length from 5.28 to 7.77 (average 6.16) mm. and in maxi- mum body width from 0.44 to 0.56 mm. The cuticula is thin and has striations about 0.010 mm. apart. There are no lateral or cervical cuticular alae. Caudal alae are present in the male. The cephalic region is distinct (fig. 10) and terminates anteriorly in the rounded lips. The three lips are separated from one another by distinct grooves. The lips bound a Y-shaped mouth (fig. 11) which 144 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 communicates with the shallow buccal cavity. The anterior end of the esophagus is rounded and extends into the buccal cavity. There are two papillae near the anterolateral margin of each of the lips. Each of the ventrolateral lips has two additional papillae situated near the median anterior margin; these papillae could be seen distinctly in the lateral view but were not apparent in the en face view. There is thus a total of 10 papillae on the lips. The well-developed amphids terminate near the median anterior margins of the ventrolateral lips. The excretory pore is ventral and prebulbar in both sexes, being 1.48 mm. in the male and 1.73 mm. in the female from the anterior end. The pore communicates with an excretory vesicle which connects with the excretory canals. The canals form an “X”’ where they lead to the vesi- cle. The nerve ring is 0.258 mm. in the male and 0.263 mm. in the female from the anterior end. The position of the nerve ring seems to be quite constant, varying little in the specimens of different sizes. The esophagus varies in length from 1.43 to 1.69 (average 1.55) mm. in the male and from 2.01 to 2.13 (average 2.08) mm. in the female. Its posterior end terminates in the subspherical bulb, which is equipped with cuticularized valvular structures. There is a constriction, the isth- mus, between the bulb and the anterior portion, or the corpus of the esophagus. The rectilinear intestine is enlarged into a bulblike region at its anterior end. Male: ‘The body of the male ends in a ventrally directed, bluntly rounded tail, which varies in length from 0.11 to 0.20 mm. Laterally the tail is provided with wide caudal alae (fig. 14), extending from the base of the tail to the base of the caudal papillae. There are two pairs of precloacal genital papillae (figs. 13 and 14), one pair of adcloacal papillae, and one pair of caudal papillae located at the posterior end of the alae. The precloacal pairs seem to arise from the same base on each side, and thus are interpreted as double papillae. Each has a separate nerve ending and the nerve fibers could be seen to branch from a common stem to each of the papillae. These papillae are considered sessile. Adjacent to these papillae are two fingerlike projec- tions, the cloacal lips. The adcloacal papillae are situated on long slender stalks which arise from the body anterior to the cloacal aperture. ‘These two papillae are well developed and are between the cloacal lips and accessory piece. The pedunculated caudal papillae are situated at the anterior of the distal quarter of the tail. Thus there are four pairs of genital papillae, two of which are sessile and two are pedunculated. No. 9 CUCKLER: NEMATODE PARASITES 145 There is a single spicule (fig. 12). The length varies from 1.36 to 1.58 (average 1.47) mm., about two fifths of the body length. The proximal end of the spicule is dilated to form a head where the muscles are attached. The distal end of the spicule is sharply pointed. A short distance from the distal end the spicule is enlarged laterally and at this point possesses a curve which is ventrally directed. There is a well-developed, V-shaped accessory piece (fig. 14), which measures 0.084 mm. in width by 0.080 mm. in length. The distal point of the accessory piece is directed ventrally, forming a conspicuous hooked tip. At the base of the accessory piece on each side there is a tubular cavity which seems to open to the outside at the base of the tail. The significance of this structure was not determined. Female: The vulva is situated on the ventral surface 0.35 mm. posterior to the middle of the body. It varies from 2.83 to 3.96 (aver- age 3.40) mm. from the anterior end. In the fully mature specimens there is a cuticular flap around the anterior margin of the vulva. Sur- rounding the distal end of the vagina and near the body wall, large gland cells can be distinguished in the immature specimens, but they are not apparent in the fully mature individuals. It seems probable that these gland cells are concerned with the development of the flap around the vulva. The vulva communicates with the muscular vagina which is directed anteriorly and then curves posteriorly where it is continued as a less muscular region, the ovejector. Following this region is the egg reservoir or common uterine stem. In the mature specimens the lengths of the parts of the genitalia average as follows: the vagina 0.90 mm., the ovejector 0.90 mm., and the common uterine stem 0.96 mm. The uteri are divergent, thin-walled tubes continuous with the ovaries. The ovaries are about 0.08 mm. in diameter near their mid-regions. The number of eggs in the uteri is variable; some specimens have nearly the whole body filled with them, while others have very few eggs. The eggs (fig. 9) are large and possess a relatively thin shell. The eggs vary from 0.077 to 0.098 mm. in width by 0.175 to 0.196 mm. in length, with an average size of 0.086 by 0.185 mm. The eggs are segmented in utero. SPECIFIC DIAGNOSIS OF ALAEURIS LONGISPICULA Principal characters of genus. Mature females 5.28 to 7.77 mm. by 0.47 mm.; males 3.01 to 4.27 mm. by 0.28 mm. Cephalic region dis- tinct; three conspicuous lips; lateroventral lips each with four papillae and an amphid; dorsal lip with two papillae. Lateral cuticular alae ab- 146 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 sent; caudal alae in male. Nerve ring about 0.26 mm. from anterior end. Excretory pore ventral and prebulbar, 1.48 mm. in male and 1.73 mm. in female from anterior end. Esophagus typical and about one- third body length in female and about three-sevenths body length in male. Male: Tail 0.14 mm. long. Spicule 1.36 to 1.58 mm. long. Acces- sory piece well developed, V-shaped, 0.084 by 0.080 mm. Four pairs genital papillae. “Iwo precloacal pairs sessile, adcloacal pair on long stalks, and caudal pair stout and pedunculated. Ventral cloacal lips prominent. Caudal alae wide but only slightly extended ventrally; pos- teriorly extend from body to caudal papillae. Female: Vulva slightly posterior to middle of body. Prominent an- terior vulvar flap. Uteri divergent; connected to ovejector by a common uterine stem. Eggs ellipsoidal, asymmetrically flattened, 0.086 by 0.185 mm. Tail long and pointed, measuring 0.76 mm. ‘The species name refers to the long spicule. Affinities: 4. longispicula may be distinguished from 4. alaeuris on the basis of the prebulbar position of the excretory pore, the greater number of cephalic papillae, the character of the precloacal papillae, the well-developed, pedunculated caudal papillae, the much longer spicule, and the larger accessory piece. A. longispicula may be distinguished from A. iguanae on the basis of its larger size, the prebulbar position of the excretory pore, the dis- tinct cephalic region, the presence of the common uterine stem, the unstriated alae, the precloacal sessile papillae, and the longer spicule and accessory piece. The characteristics which distinguish this species from 4. hirsutus are its smaller size, the relatively greater length of the esophagus, the larger number of cephalic papillae, the character of the genital papillae, the fact that the caudal alae extend to the anterior of the distal fourth of the tail, and the slightly longer spicule. A. longispicula may be differentiated from 4. conspicua on the basis of the absence of lateral alae, the prebulbar position of the excretory pore, the greater length and different shape of the spicule, the absence of the spike on the male tail, and the character and number of genital papillae. The characteristics which distinguish 4. longispicula from A. gala- pagensis are the following: the stouter and longer body, the relatively more posterior vulva, the more distinctly separated lips, and bluntly NO. 9 CUCKLER: NEMATODE PARASITES 147 rounded rather than truncate cephalic region, the absence of cuticular- ized structures on the anterior end of the esophagus, the differences in the genital papillae, and the longer spicule. Alaeuris labicula, new species (Plate 14, figs. 15-21) This species of Alaeuris composed about 10 per cent of the entire collection. These are medium-sized oxyurids. The length of the male (fig. 15) varies from 3.11 to 3.45 mm., with an average of 3.28 mm. The maxi- mum body width is from 0.19 to 0.26 (average 0.24) mm. The size of the mature female (fig. 16) ranges from 5.51 to 6.08 (average 5.34) mm. in length by 0.44 to 0.53 (average 0.47) mm. in width. The cuticula is thick and has distinct transverse striations about 0.005 mm. apart. There are no lateral or cervical alae, although the male has wide caudal alae. The anterior end of this species is bluntly rounded, and the cephalic region (fig. 17) is indistinct. The lips are inconspicuous. The mouth is terminal and triangular in shape; it is surrounded by three lips which are best seen en face view. In some specimens examined a slight inden- tation about mid-way between the corners of the mouth could be seen on the anterior margin of each lip. It was considered at first that this perhaps indicated a slightly bilobed condition of the lips, but when other specimens were examined the same condition was not found. There is apparently a slight variation in the lip margins but the lips are never distinctly bilobed. There are eight cephalic papillae and two amphids. The amphids are conspicuous. They terminate near the posterior margins of the ventrolateral lips. The papillae are arranged in two circles, each con- taining four papillae. The papillae in the outer circle are larger than those of the inner circle. Two of the outer circle papillae are arranged on the dorsal lip, opposite the dorsal corners of the mouth. The other two external circle papillae are on the ventrolateral lips, and are located lateral to the ventral corner of the mouth. The internal circle papillae are situated on the ventrolateral lips. he papillae are arranged in an unusual manner, as they seem to show bilateral symmetry, rather than radial symmetry, as might be expected from the radial arrangement of the lips. 148 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 There is a shallow buccal cavity which is followed by the esophagus. The anterior end of the esophagus is cuticularized, and the inner mar- gins of the esophageal walls are extended anteriorly and outward to form a buccal cavity rim. In an optical section of the lateral surface of the cephalic region, the buccal cavity rim may be seen as a toothlike projection arising from the wall of the esophagus. The nerve ring encircles the anterior end of the esophagus from 0.175 to 0.210 (average 0.186) mm. in the male and from 0.196 to 0.224 (average 0.200) mm. in the female from the anterior end of the body. The excretory pore is slightly prebulbar in both sexes. The dis- tance the pore is located from the anterior end of the body varies from 1.08 to 1.51 mm. in the male and from 1.28 to 1.70 mm. in the female. The excretory pore and canals are similar to those described for the other species of Alaeuris. The esophagus is elongated, slender and mus- cular throughout its length. It terminates posteriorly in a subspherical bulb. The entire esophagus varies in length from 1.12 to 1.37 (average 1.26) mm. The ratio of esophagus to body length is about two fifths in the male and one fourth in the female. The anterior part of the esopha- gus which is in contact with the buccal cavity is bluntly rounded and heavily cuticularized. Posteriorly the esophagus connects with the en- larged bulblike region of the intestine. Male: ‘The reproductive organs are similar to those described for the other species of Alaeuris. There are three pairs of genital papillae (figs. 19 and 20). Two of the pairs are circumcloacal and the third is caudal in position. The precloacal papillae are sessile, but situated on prominent body eminences. Dorsal and slightly lateral to these papillae are two stalks which project posteriorly beyond the limits of the pa- pillae. These structures are the cloacal lips which are similar in appear- ance to the papillae-bearing stalks, but a careful examination of all of the specimens studied was made and no papillae were distinguished. The second pair of circumcloacal papillae is located on long peduncles which arise from the posterior body wall. They are lateral to the accessory piece. The third pair of papillae is situated on relatively stout peduncles which arise from the tail. The caudal alae (fig. 20) are smooth. They extend laterally almost the body width, but ventrally only a short distance, almost to the dorsal side of the accessory piece. There is a single sharply pointed spicule (fig. 15). The length varies from 0.689 to 0.792 mm., with an average of 0.739 mm. Near the NO. 9 CUCKLER: NEMATODE PARASITES 149 anterior of the distal quarter the spicule is dorsoventrally thickened. There is a well-developed, V-shaped accessory piece, measuring 0.052 mm. in width by 0.075 mm. in length. The tip of the accessory piece is directed posteriorly and laterally, usually to the right. In no instance was the tip ventrally directed or hooked. Female: ‘The reproductive system is typical. The vulva is slightly anterior to the middle of the body. The average distance from the an- terior of the body to the vulva is 2.96 mm., which is about 0.01 mm. less than half the body length. The anterior margin of the vulva is sur- rounded by a cuticular expansion. The vagina is large and muscular, being 0.80 mm. in length by 0.09 mm. in width. The internal end of the vagina is swollen into a bulb-shaped enlargement; connected with this structure is a less muscular region, the ovejector, about 0.56 mm. in length. The uteri are joined to this by a common stem which has an average length of 0.41 mm. and a width of 0.05 mm. The eggs (fig. 21) are segmented in utero. The eggs are large, thin- shelled, asymmetrically flattened, and have an average size of 0.087 by 0.192 mm. SPECIFIC DIAGNOSIS OF ALAEURIS LABICULA Principal characters of genus. Medium-sized oxyurids, the males ranging from 3.11 to 3.46 mm. by 0.19 to 0.26 mm. and the females from 5.57 to 6.80 mm. by 0.44 to 0.53 mm. Posterior extremity of fe- male has a pointed tail about 0.72 mm. long; male with a short bluntly rounded tail about 0.12 mm. long. No lateral or cervical alae; wide caudal alae in male. Cephalic region indistinct ; three inconspicuous lips. Mouth triangular. Eight cephalic papillae and two amphids. Papillae arranged lateral to mouth, exhibiting bilateral symmetry, rather than radial. Nerve ring encircles esophagus 0.18 mm. in male and 0.20 mm. in female from anterior end. Excretory pore slightly prebulbar in both sexes, varying from 1.08 to 1.31 mm. in the male and from 1.28 to 1.70 mm. in the female from anterior extremity. Esophagus ranges from 1.12 to 1.37 mm. in the male and from 1.34 to 1.42 mm. in the female in length. Male: Three pairs genital papillae; precloacal papillae sessile and on body eminences; adcloacal papillae on long peduncles; caudal pa- pillae on short, stout peduncles, anterior to tip of tail. Cloacal lips con- spicuous, resemble papillae-bearing stalks. Caudal alae wide. Spicule sharply pointed, about 0.73 mm. long. Accessory piece well developed, 150 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 V-shaped, 0.052 mm. wide by 0.075 mm. long; its tip is directed later- ally, never ventrally. Female: Vulva slightly anterior mid-body. Muscular vagina and ovejector; divergent uteri connected to ovejector by a common uterine stem. Eggs thin-shelled, asymmetrically flattened; average size 0.087 by 0.192 mm.; segmented in utero. The species name refers to the small lips. Affinities: The structures which distinguish this species from 4. alaeuris are: the prebulbar position of the excretory pore, the longer (0.030 mm.) eggs, the much longer spicule, an accessory piece nearly twice as long, the indistinct cephalic region, the inconspicuous lips, two pairs of circumcloacal papillae instead of three, and the character of the cloacal lips. It may be distinguished from A. iguanae on the basis of its larger size, the prebulbar excretory pore, the absence of tooth-like processes along the inner edge of the lips, the presence of the common uterine stem, the character of the circumcloacal papillae, the longer spicule, and the longer accessory piece. The characters which differentiate this species from 4. hirsutus are its smaller size, the indistinct cephalic region, the inconspicuous lips, the greater number of cephalic papillae, the extension of the tail pos- terior to the caudal alae, the character and disposition of the circum- cloacal papillae, the shorter spicule, and the longer accessory piece. This species may be distinguished from 4. conspicua by the absence of lateral alae, the inconspicuous lips, the greater number of cephalic papillae, the structure of the esophagus, the prebulbar position of the excretory pore, the more anteriorly situated vulva, the absence of the spike on the male tail, and the shorter spicule. The characters which distinguish this species from 4. galapagensis are the following: the indistinct cephalic region, the inconspicuous lips, the number of cephalic papillae, the absence of cuticularized projec- tions on the anterior end of the esophagus, the more anterior position of the vulva, the differences in the genital papillae, the greater length of the spicule, and the laterally directed tip of the accessory piece. This species may be distinguished from 4. longispicula on the basis of the indistinct cephalic region, the inconspicuous lips, the number and position of the cephalic papillae, the much shorter spicule, the shape and direction of the tip of the accessory piece, the number of genital papillae, and the differences in the cloacal lips. No. 9 CUCKLER: NEMATODE PARASITES 151 Alaeuris conolophi, new species (Plate 15, figs. 22-27) The following description is based upon a study of the least num- erous animals in the collection. There were 40 males and 90 females of this species, approximately 3 per cent of the entire collection. The females that are assigned to this species are all immature, but they possess certain resemblances to the males, especially in the structure of the lips and the anterior end of the esophagus. There is a slight differ- ence in the relative position of the excretory pore, which is postbulbar, but this difference may be due to the immaturity of the specimens. The animals are slender and spindle-shaped. From the mid-body region the body gradually tapers anteriorly to the rounded cephalic region and posteriorly to the short, blunt tail of the male, or to the slender, long pointed tail of the female. The length of the male (fig. 22) ranges from 3.10 to 3.91 (average 3.42) mm. The females (fig. 23) range from 2.81 to 3.26 (average 2.98) mm. in length by 0.18 to 0.24 (average 0.21) mm. in maximum width. There is a thin, clear cuticula which has striations about 0.008 mm. apart. The females have no cervical or lateral alae, but the males pos- sess a thickened cuticula in the lateral line region of the posterior ex- tremity of the body. This region extends anteriorly from the cloacal region for about 0.144 mm. and at this point the cuticula becomes the same thickness as that which covers the rest of the body. Whether or not these thickened regions of the cuticula are evidences of lateral alae would be a matter of individual interpretation. It is interesting to note, however, that this is the only indication of possible lateral alae en- countered in this study of four species of 4/aeuris. The cephalic region (fig. 24) is evident in the female, but slightly less evident in the male. The lips are slightly lobed. The mouth is termi- nal and is surrounded by three simple lips. The cephalic papillae (fig. 25) are located on the anterior margins of the lips. There are six cephalic papillae and two amphids. Each of the lips has two papillae near the median anterior margin; amphids are present on the ventro- lateral lips. The number and arrangement of the papillae are the same in the male and the immature female. There is a very shallow buccal cavity. The anterior end of the esophagus is bluntly rounded and cuticularized. No projections arise from the esophageal wall. The nerve ring encircles the anterior end 152 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 of the esophagus 0.189 to 0.210 mm. in the male and 0.175 to 0.182 mm. in the female from the anterior end of the body. The excretory pore is ventral. In the male the pore is located from 1.01 to 1.19 mm. from the anterior end, and in the female it is located 0.86 to 0.99 mm. from the anterior end. The esophagus is of the same muscular structure throughout its length, except the anterior end which is cuticularized for a short distance. The posterior end of the esophagus has a subspherical bulb which averages 0.140 mm. in diameter in the males and 0.082 mm. in the females. The esophageal bulb is equipped with valvular struc- tures. The length of the esophagus, including the bulb, is from 1.21 to 1.35 mm. in the male and 0.70 to 0.79 in the female; the width of the anterior portion of the esophagus is about 0.035 mm. The esophagus in the male is about one third the body length, and one fourth the body length in the female. The anterior end of the intestine is enlarged into a flask-shaped region 0.187 mm. in the male and 0.129 mm. in the female in diameter. The diameter of the intestine gradually diminishes from this point to the mid-region where it continues uniformly to the posterior. Male: ‘The posterior end of the body has a ventrally directed, bluntly rounded tail, varying from 0.096 to 0.115 mm. in length. The tail has wide alae which extend from the ventral body cleft to the anterior of the distal fourth of the tail. The seminal vesicle has a length of about 0.5 mm. and a width of about 0.15 mm. The acicular spicule varies in length from 0.384 to 0.480 (average 0.437) mm. The acces- sory piece is 0.048 mm. wide by 0.056 mm. long. It is straight and widely V-shaped. Three pairs of genital papillae (figs. 26 and 27) are situated around the cloaca at the ventral body cleft and on the ventral side of the tail. One pair is precloacal and sessile, although situated on prominent projec- tions from the body. The adcloacal papillae are on long peduncles. The third pair of papillae is located at the anterior of the distal fourth of the tail. These papillae are situated on prominent, stout peduncles. Female: The tail averages 0.49 mm. in length and is finely pointed. The vulva ranges from 1.40 to 1.59 (average 1.44) mm. from the an- terior end. None of the reproductive organs are fully developed. SPECIFIC DIAGNOSIS OF ALAEURIS CONOLOPHI Principal characters of genus. Medium-sized oxyurids; mature males average 3.42 mm. in length by 0.23 mm. in width; immature females NO. 9 CUCKLER: NEMATODE PARASITES 153 average 2.98 mm. in length by 0.21 mm. in width. No lateral alae in female; thickened cuticular regions along posterior end of male may indicate lateral alae; wide caudal alae in male. Cephalic region evi- dent; three simple lips each with two papillae; ventrolateral lips each with an amphid. Esophagus typical, about one third body length in mature male, and about one fourth body length in immature female. Excretory pore slightly prebulbar in male, and slightly postbulbar in immature female. Male: Single acicular spicule, 0.437 mm. long. Straight accessory piece 0.048 mm. wide by 0.056 mm. long. Three pairs genital papillae. One precloacal pair of sessile papillae; one pair of adcloacal peduncu- lated papillae; one pair of stout, pedunculated caudal papillae. Caudal alae wide, extend posteriorly to caudal papillae. Female: Immature specimens only available. Vulva slightly pos- terior to mid-body. Tail 0.49 mm. in length. This species is named after the genus of its host, Conolophus. Affinities: This species may be distinguished from A. alaeuris by the absence of conspicuous lateral alae in the male, the relatively longer female tail, the character and disposition of the genital papillae, and the length of the spicule. It differs from 4. iguanae in the absence of toothlike processes on the inner edges of the lips, the relative length of the female tail, the unstriated caudal alae, the number and disposition of the genital papillae, and the length of the spicule. Its differences from 4. hirsutus are the size, the character and num- ber of the genital papillae, the extent of the male tail beyond the caudal alae, and the much shorter spicule. The distinguishing differences between this species and 4. conspicua are the absence of conspicuous lateral alae, the absence of the spike on the male tail, the number and position of the genital papillae, and the length of the spicule. It differs from 4. galapagensis in the number of cephalic papillae, the absence of toothlike processes arising from the anterior end of the esophagus, the character of the genital papillae, the shape of the tail of the male and the shape of the caudal alae, the slight difference in the size of the spicule, and the size and shape of the accessory piece. This species may be distinguished from 4. longispicula on the basis of the form of the lips and the number of cephalic papillae, the length and shape of the tail of the male, the great difference in the length of 154 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 the spicule, the size and shape of the accessory piece, the fewer genital papillae, and the shape of the caudal alae. The following characters distinguish this species from 4. labicula: the number of cephalic papillae, the shape of the mouth, the more distinct lips, the nature of the genital papillae, the absence of distinct cloacal lips, the size of the spicule, the size and shape of the caudal alae, and the size and form of the male tail. Paralaeuris dorochila, new genus, new species (Plate 15, figs. 28-33) The following description is based on the study of the smallest worms in the collection. About 8 per cent of the collection consisted of animals of this species. The body is spindle-shaped, tapering from about mid-body region to the bluntly rounded cephalic region, and posteriorly more abruptly to the long, finely pointed tail. The length of the male (fig. 28) varies from 1.12 to 1.81 (average 1.41) mm. and the width varies from 0.084 to 0.147 (average 0.110) mm. The length of the female (fig. 29) varies from 2.17 to 3.80 (average 2.79) mm. and the width varies from 0.161 to 0.245 (average 0.188) mm. The body is covered with a clear cuticula which has distinct stria- tions about 0.008 mm. apart. There are no lateral or cervical alae in either sex. The male has well-developed caudal alae. The cephalic region (fig. 30) is indistinct. The diameter of the cephalic region at the base of the lips is about 0.030 mm. There are three simple lips which are bluntly rounded and slightly separated from each other, and difficult to distinguish. The shape of the mouth and the relation of the lips to the mouth were not determined as no satisfac- tory en face views of the lips were secured. There are six cephalic papillae; two papillae are situated near the anterior margin of each of the lips. Amphids were not observed. Each of the ventrolateral lips has a small, sharply pointed, cuticularized an- teriorly projecting structure which arises from the inner margin of the lip. The esophagus is of the typical oxyurid structure. It is muscular throughout its length and is terminated posteriorly by a subspherical bulb. The anterior end of the esophagus is bluntly rounded and slightly larger than the mid-region. There is no constriction or isthmus between NO. 9 CUCKLER: NEMATODE PARASITES 155 the bulb and the corpus of the esophagus. The bulb possesses the usual valvular structures. The length of the esophagus including the bulb varies from 0.252 to 0.371 (average 0.315) mm. in the male, by 0.011 to 0.019 mm. in width; the esophagus length in the female varies from 0.280 to 0.601 (average 0.375) mm. by 0.017 to 0.024 mm. in width. The anterior end of the intestine is slightly enlarged where it joins the esophageal bulb. The diameter of this region is about 0.044 mm. in the male and 0.065 mm. in the female. The excretory pore is ventral and postbulbar, averaging 0.408 mm. in the male and 0.522 mm. in the female from the anterior end. The excretory pore is situated near the center of the excretory vesicle, which is oval in shape and 0.034 mm. in length. The excretory canals may be traced from the lateral line areas to the vesicle. The nerve ring encircles the esophagus at a point 0.106 mm. in the male and 0.116 mm. in the female from the anterior end. Male: The tail is 0.202 mm. long, about one seventh of the body length. The male reproductive organs consist of a single testis, the an- terior end of which is coiled on itself at the anterior of the intestine, and a slightly enlarged seminal vesicle which communicates with the cloaca. There is a single sharply pointed spicule (fig. 32) varying from 0.056 to 0.075 (average 0.065) mm. in length. A V-shaped accessory piece is present, which measures 0.018 mm. in length. There are four pairs of genital papillae (figs. 32 and 33). Three pairs of the papillae are precloacal and pedunculated ; two pairs of these seem to arise from common stalks, forming a double papilla on each side. The other pair of precloacal papillae arises from independent, elongated peduncles which are lateral and dorsal to the double papillae. The fourth pair of papillae is caudal in position, arising 0.040 mm. posterior to the cloacal aperture, and their long stalks support the caudal alae. The caudal alae are wide and well developed. Anteriorly the alae arise from the cloacal region and extend posterior to the caudal papillae. There are cuticular bands in the cloacal region, both ventrally and dorsally, extending from one side of the body to the other. Female: he tail is relatively long, measuring 0.723 mm., about one fourth of the entire body length. The vulva is anterior to the middle of the body, varying from 0.805 to 1.701 (average 1.160) mm. from the anterior end. The vagina, about 0.372 mm. long, connects with the vulva obliquely; it is directed anteriorly and then curves posteriorly to connect with the ovejector which terminates in a bulb. The ovejector 156 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 is about 0.35 mm. in length, and joins the divergent uteri. The thin- shelled, asymmetrically flattened eggs are segmented in utero. The eggs vary in size from 0.038 to 0.049 mm. wide by 0.075 to 0.105 mm. long, with an average size of 0.042 by 0.092 mm. GENERIC DIAGNOSIS OF PARALAEURIS Small slender oxyurids; tail long in both sexes, about one seventh body length in male and about one fourth body length in female. Male tail with wide caudal alae. No lateral alae in either sex. Cephalic region indistinct; three simple lips, each with two papillae; ventrolateral lips each with a small anteriorly directed cuticular process. Esophagus rela- tively short, muscular throughout its length. Excretory pore postbulbar. Vulva slightly anterior to mid-body; ovejector present; two uteri and two ovaries present. Eggs small, elongated. Male with single, short, stout, and sharply pointed spicule. V-shaped accessory piece present. Four pairs pedunculated papillae, three of which are precloacal, and the fourth pair support wide caudal alae. Type species: Paralaeuris dorochila from the intestine of Conolo- phus subcristatus Gray. Affinities: —TThe presence of a single spicule and an accessory piece places this genus in the subfamily Syphaciinae Railliet, 1916. There are five genera in this subfamily all of which are parasites of reptiles. Only two of the genera, Alaeuris Thapar, 1925 and Thaparia Ortlepp, 1933 have caudal alae in the males. his genus resembles 4laeuris and Thaparia in the presence of caudal alae. However, the smaller size, the relative length of the esophagus to the body, the shape and length of the spicule, the position of the vulva, the position of the excretory pore, the relative length of the tail, the character of the genital papillae, and the structure of the caudal alae are characters in which this genus differs from Alaeuris and Thaparia. This genus has a superficial resemblance to Pharyngodon Diesing, 1861 of the subfamily Oxyurinae Hall, 1916. It differs from it in the presence of the accessory piece, the absence of lateral alae, the relative position of the vulva to the excretory pore, and the presence of an ovejector. The closest resemblance between this genus and the known genera of reptilian oxyurids is with the genus Alaeuris Thapar, 1925. Thus the name Paralaeuris is proposed for this genus. | | | NO. 9 CUCKLER: NEMATODE PARASITES 157 SPECIFIC DIAGNOSIS OF PARALAEURIS DOROCHILA Characters of the genus. Males from 1.11 to 1.80 mm. in length by 0.08 to 0.14 mm. in width; females from 2.17 to 3.80 mm. in length by 0.16 to 0.24 mm. in width. Thick cuticula, striations about 0.008 mm. apart. No cervical or lateral alae; caudal alae in male. Cephalic region indistinct; three simple lips, slightly lobed; each lip with two papillae; each ventrolateral lip with a short, anteriorly directed, pointed process. Esophagus 0.31 mm. long, about one fourth body length, in male and 0.37 mm., about one seventh body length, in female. Nerve ring 0.108 mm. in the male and 0.116 mm. in female from anterior end. Excretory pore postbulbar, 0.40 mm. in male and 0.52 mm. in female from an- terior end. Male: Alate tail 0.20 mm. long, about one seventh body length. Single short, pointed spicule, 0.065 mm. in length. V-shaped accessory piece 0.018 mm. long. Four pairs of pedunculated genital papillae. ‘Three pairs precloacal, one pair caudal in position. wo pairs arise from com- mon stalks, forming double papillae; third pair on long peduncles, lateral and dorsal to double papillae; fourth pair on long ray-like peduncles supporting caudal alae. Wide caudal alae extend slightly posterior to caudal papillae. Female: Long finely pointed tail 0.723 mm. in length, about one fourth body length. Vulva anterior to mid-body, averaging 1.16 mm. from anterior end. Vagina about 0.37 mm. long, and ovejector about 0.035 mm. in length. Eggs average 0.042 mm. by 0.092 mm.; segmented in utero. The species name refers to the cuticular projections on the lips. SUMMARY 1. Five species of nematode parasites are reported from the Gala- pagos land iguana, Conolophus subcristatus Gray. Apparently, these are the first nematode parasites reported from this iguana. 2. Of the five species of parasites reported, four are assigned to the genus Alaeuris Thapar, 1925. Each of these species is new. The new species described are: 4. galapagensis, A. longispicula, A. labicula, and 4. conolophi. 3. The other species reported is assigned to a new genus. The name Paralaeuris is proposed for this genus. A new species, P. dorochila, is described in this genus. 158 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 LITERATURE CITED Bayuis, H. A. and R. DAUBNEY 1926. A synopsis of the families and genera of Nematoda. Cuitwoop, B. G. and Everett E. WEHR 1935. The value of cephalic structures in nematode classification, with special reference to the superfamily SPIRUROIDEA. Zeit. Parasit., 7: 273-335. OrTLEPP, R. J. 1935. On some South African reptilian oxyurids. Onderstepoort Journ. Vet. Sci. Animal Ind., 1: 99-114. SANDGROUND, J. H. 1929. Some new parasitic nematodes from Yucatan (Mexico), including a new genus of strongyle from cattle. Bul. Mus. Comp. Zool. Harvard, 69: 523-524. THApAR, G. S. 1925. Studies on the Oxyurid parasites of reptiles. Jour. Helmin., 3: 83-150. YorkKE, W., and P. A. MAPLESTONE 1926. ‘The nematode parasites of vertebrates. .