Three new Trematodes found priucipally in Black Bass. 481 



at their point of union a small yolk reservoir is formed. Latirer's 

 canal, if present, was not seen. The Uterus is not uearly so pro- 

 minent as in most distomes, its entire length is not very mucli 

 greater that that of the fluke. It Starts from a point near the 

 Center of the body in the ventral half and descends on the light 

 side in an irregulär, bending- manner; before the posterior end of 

 the body is reached. it passes to the left side ascending here in a 

 manner similar to that of its descent. In no specimens were the 

 eg-g-s so numerous as to greatl}^ obstruct a view of the other organs. 



Leuceruthf'iis niicroptef'l n. (j. n. sp. 



Body tongue-shaped, the anterior end blunt, the posterior end 

 pointed (Fig. 8). Length from 4 to 7 mm. Body smooth. Oral 

 sucker well developed ventral in position near anterior end of body; 

 acetabulum one-half the size of oral sucker, median, a little anterior 

 to center of body. AVell developed pharynx present; intestinal caeca 

 extend to end of body. Excretory vesicle Yshaped, the median stem 

 extending to the ovary, the lateral branches into anterior part of 

 the body. Genital pore median a little anterior to the acetabulum. 

 Testes, one diagonally behind the other, a little posterior to the 

 acetabulum. Oopulatory apparatus present. Ovary median, midway 

 between the festes and the posterior end of the body. Yolk giands 

 lateral in the posterior half of the body. Laurer's canal present. 

 Habitat, mouth and stomach of large- and small-mouth black bass. 



In the black bass examined, this distome was found offener than 

 either of the other two. A large majority of the specimens were 

 taken from the stomach, a few in the mouth or on the gills. It is 

 easily recognized by its peculiar pinkish or yellowish finge hardly 

 dark enough to be described as red or yellow. It was found in 

 black bass from all three of the Madison lakes and from Round Lake. 



The oral sucker is large, 0,75 mm, in diameter and is situated 

 ventral just behind the anterior margin of the body. (All the 

 measurements were taken from a specimen 5 mm long.) The aceta- 

 bulum, diameter, 0,45 mm, is median, a little in front of the center 

 of the body. The pharynx is large, praepharynx and Oesophagus 

 absent. The intestinal caeca extend to the posterior part of the 

 body; each caecum at first extends forward for a short distance 

 before passing backward. 



The excretory vesicle is Yshaped, the excretory pore terminal^ 

 opening into a short, narrow tube which enters the median vesicle. 



