686 



lateral from the ventral sucker, immediately behind the ends of the 

 coeca; in B. turgida they are lateral from the coeca, the right one 

 being oi^posite the interval between oral sucker and ovary. The 

 ovary in the former worm is to the right of the median line and in 

 front of the testes, but in the latter it is on the median line and 

 almost behind the testes. The penis-sac in the one lies obliquely 

 across the left coecum, far in front of the acetabulum, in the other 

 it lies transversely from the ventral sucker, some distance behind 

 the end of the left coecum. According to Nickerson the male and 

 female genital ducts open separately on the surface or into a com- 

 mon groove or depression, the female in front of the male, both on 



^ the ventral surface, near the left side, and rather nearer the oral 

 than the ventral sucker. I must say that my specimens seem to 

 agree with this but that, on account of the presence of vittelline 

 follicles, I am not yet fully satisfied as to the separate openings. In 

 Brandesia the genital pore is marginal. In the American worm the 

 folds of the uterus are, for the most part, behind the ventral sucker, 

 in the European they pass first to the left and then forwards across 

 the region of the coeca and pharynx. In the first the vitellaria 

 extend all the way across the intestinal region, but in the second 

 they are in lateral bunches anterior to the coeca. The egg of 

 L. arcanu?n measures about 0,022 X 0,014, that of ß. turgida 

 0,038 X 0,013. 



68) Olypthelmiiis quieta. 



Intes. Rana catesbiana Shaw (Bull, Frog). Rana virescens Kalm. 

 (Com. Frog). Hy la pickerÌ7igii 'Soih. (Tree Frog). 

 New genus: ylv/trôç^ carved; eli.iirg, v^orm. In the Zool. Jahrb. 

 Bd. 13. Hft. 5. 1900. p. 403 I first described this worm and naturally 

 associated it with Opisthioglyphe endoloha Duj. as described and illu- 

 strated by Loos 1894, von Linstow '88, Schwarze '85, Olsson 

 ^76, van Bene den '61. It has the same habitat (excepting that 

 it is in different species of frog) ; about the same size and shape ; a 

 similar position of the suckers; spines; the intestine has the same 

 parts, relative sizes and positions; the vitellaria, ovary, genital pore 

 have approximately the same positions; it has both receptaculum 

 seminis and Laurer's canal. Such small differences as occur in the 

 above mentioned organs might be considered as of sj)ecific value. One 

 can not so regard the position of the testes and the length and po- 

 sition of the uterus. These give to the worm a distinctly different 

 type. The testes are small, spherical, placed obliquely or almost 

 parallel, in the middle of the body, close behind the ventral sucker, 

 instead of being large, transversely elongated, in a line one behind 



