I'ARASITES OF FISHES OF THE WOODS HOLE REGION. 429 



4. Aararls sp. [PI. XI, figs. 127-130.] 



A few specimens found in the intestine on different occasions, inimatnre, most of tlieni certainly 

 young ascarids. They have evidently l)een introduced with the food and i)robably would not develop 

 further in this host. The specimen shown in figs. 127-128 was collected .Vugust 2, 1886. Length, 17 mm. ; 

 maximum diameter from middle to posterior third of body, 0.57 mm.; body crossed with transverse 

 strise; wall of intestine tessellated. Figs. 129-130 show an immature female, length, 50 mm. ; diameter, 

 miildle to posterior lifth, l.li mm. 



CESTODES. 



5. Crossohotlirlinii hii-iiiintnm IJnton. Spiral valve. 1, jip. 4WI— 174, pi. in, tigs. 4-lS. 2, jip. 799-802, 



pi. vn, fig. 4. 5, pp. 445-446. 7, p. 27.3. 



July 17, 1899; 20. July 21, 1899; several. Aug. 9, 1899; numerous. Aug. 12, 1899; 2. Aug. 15, 

 1899; 1. In this sjiecimen the stomach was empty, the intestine contained a viscid mucus and there 

 was a diseased patch of mucous membrane at pyloric end of stomach, the surface being caked and 

 hard. Aug. 17, 1899; 4. Aug. 18, 1899; 55, large and .small. Aug. 19. 1899; 12. July 20, 1900; 

 47 from one and 16 from another, young and adult. Two small worms in this lot present some 

 points of difference from the young of this species with which they were a,ssociated. Bothria provided 

 with an auxiliary acetabulum as in CronKohuthrmin but smaller, more slender, and less mobile; bodv 

 •slender, with aiijiarently true proglottides, which were elongated and without any in<lication of 

 lacinia?. Habit of worm like that of form heretofore called by me On/tpiiatohnlliHnin fUKjii.tliini. .Vug, 

 12, 1900; numerous. -Vug. 13, 1900; 106, young and adult, with numerous free, ripe i)roglottides. 



Dr. Dahlgren reports that many sand sharks have lieen opened this season (July-August, 1900) 

 to supply material for work on cestodes in the Marine Biological Laboratory, and that this si)eciea has 

 been found in great abundance in all of them. This species maybe identical with Telrabotlirium. barha- 

 tuni Leidy. Fig. 235 is a sketch of the posterior end of a young stroliile which ai>peared tc.> be dividing 

 into four by the abnormal enlargement of the laciniit. 



6. Rhynchohothrium hngicorui' Linton. Spiral valve. !i, pp. .S47-849, ]il. in, figs. 4-8. 5, p. 450. 



Aug. 9, 1899; 4. 



7. Ehijnchobothriiim. Encysted in walls of stomach and intestine. 4, p. 798. .Vug. 18, 1899; blastocyst 



from cyst in stomach wall. 



Isurus dekayi, ifiukcrcl Shark. 



I'ooD. 



One specimen, taken by the schooner (irainpns, July 30, lOOO, had a conger eel and fragments of 

 fish in the stomach. Entozoa collected by Mr. C. W. Stone, in formalin when examined. 



N'E.M.VTODES. 



1. lininalnrc ucinatothx. Intestine. 



Few, small; length of largest, 12 mm. .Same type frei|Uently found in a greal variety of fish. A 

 diverticulum from base of proboscis and another from anterior end of intestine. 



CE.STODES. 



2. Aiilh<ib(jlltriii,in tiwinintiim Linton. Spiral valve. Not recorded before from this host. See under 



Vdrchfiriiwii obsnnrnx, No. 3. 

 The.se individuals, 5 in number, are smaller than specimens from the dusky shark. Dimensions 

 in millimeters: Length, 5; breadth of head, 0.61; length of head, 0.34; diameter of neck, 0.09; distance 

 of first segment from head, 0.3(i; last segment, length 0.58, Vjreadtb 0.43. 



3. Monorygma sp. Spiral valve. Twelve specimens, all very small and identical with No. 4, under 



OmhnrhiuK milberli. 

 The heads of the living worms were not seen, and it is difficult to determine the exact nature of 

 the contracted specimens. There appears to be a myzorhynchus and the character of the acetaliulum 

 .seems to be quite different from that of the species 1 have been erroneously calling Oriii/inulobothnum 

 anguslnm. The auxiliary acetabulum of the latter re,«end)les that of Cronmhalhriiiiii and of Phtilkibothrium. 

 In the case of these specimens the auxiliary acetabulum is relatively larger than in the genera just 

 named and appears to be simply the anterior jmrt of the bothrium separated by a transverse partition. 



