26 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 7a 



only by careful focussing. It is a little in front of the middle, and 

 larger than the oral sucker; pharynx adjacent to the oral sucker, 

 longer than broad; esophagus about twice as long as the pharynx; 

 intestinal rami traced as far as the testes, probably extend to the 

 posterior end. The two testes are nearly transverse, a little nearer 

 to the ventral sucker than to the posterior end. The cirrus-pouch 

 is on the right of the ventral sucker, and the metraterm on the left; 

 genital pore on the median line in front of the ventral sucker. The 

 ovary is circular in outline and situated to the right of the median 

 line in front of the right testis. A vitelline reservoir on the ventro- 

 median border of the ovary, and a transverse yolk-duct, leading to 

 it from the left side, and lying in front of the left testis were 

 clearly shown. Vitellaria mainly marginal, from level of anterior 

 border of testes to posterior end. The uterus contained but few 

 ova, so distributed, however, as to indicate that it passes back be- 

 tween the testes to the posterior part of the body, and returning, 

 passes along the left border of the ventral sucker to the genital pore. 



B. Figure 58 



After mounting the distome described under A, above, another 

 small distome was found on the slide. 



Dimensions in balsam : Length 0.24 mm. ; breadth, at anterior end 

 0.09, at level of ventral sucker, maximum. 0.10; diameter of oral 

 sucker 0.08, of ventral sucker 0.018; ova, maximum, 0.018 by 0.010. 



Short, nearly linear, truncate in front, bluntly pointed at posterior 

 end. Oral sucker nearly terminal, its diameter nearly equal to 

 diameter of body. No muscular pharynx was seen, the oral sucker 

 and the esophagus appearing to be funnel-like; ventral sucker much 

 smaller than the oral, situated at about the posterior third. The 

 intestinal rami begin near the middle of the body, and reach barely 

 to the level of the ventral sucker. A conical structure on the ventral 

 side of the bifurcation of the intestine has the appearance of being 

 a diverticulum of the intestine. The genital pore was faintly indi- 

 cated at the anterior border of the ventral sucker; testes two, at 

 posterior end near lateral margins, nearly transverse ; ovary ventral, 

 and at anterior border of right testis. The vitelline gland is com- 

 pact and close to the posterior border of the ventral sucker. Ova 

 are widely distributed in the posterior half of the body. They lie 

 along the lateral margins from the level of the anterior border of 

 the testes to about the anterior third of the body. They also lie 

 between the testes, and are scattered over the median region of the 

 body both behind and in front of the ventral sucker. 



