482 ^^-^i- S. Marshall and N. C. Gilbert, 



This latter part is of moderate length. extending forward as far as 

 tlie ovary, and from its anterior margin tlie two lateral branches 

 arise and extend forward. We were unable to follow these branches 

 fiirther than tlie acetabulum but from tlieir abrupt ending and 

 thickness at the end we believe tliat they extend furtlier into tlie 

 anterior region of the hodj. 



In a ventral view, the testes are nearly circnlar in outline, 

 0,325 mm in diameter and lie nearly in the same transverse plane. 

 One is always slightly in advance of the other but neither the right 

 nor the left is constant in this respect. Both testes are near the 

 Center of the body a little posterior to the acetabulum. The vasa 

 deferentia pass forward dorsal to the acetabulum; they join at the 

 base of the cirrus-sac within which the seminal vesicle is beut upon 

 itself. finally, passing into the ductus ejaculatorius (Fig. 9) which 

 empties into the genital sinus just anterior to the female opening. 



The ovary is median, slightly lengthened along the transverse 

 axis of the fluke and is situated midway between the testes and 

 tlie posterior end of the body. A ventral view shows it lying 

 apparentlj' in the fork of the excretory vesicle. An enlarged view 

 of the ovary (Fig. 12) shows it to be filled with eggs of different 

 sizes, the largest and oldest of which are nearest tlie entrance of 

 the oviduct, the smallest and youngest near the surface. No definite 

 epithelial laj^er could be distinguished within the ovary but a layer 

 of slightly flattened cells, each with an ovoid nucleus, formed the 

 wall of the oviduct. The eggs are irregulär in shape assuming a 

 more definite form as they become larger until, finally, tliose near 

 the entrance of the oviduct are all somewhat similar. Each egg 

 (Fig. 12 a) contains a large nucleus in which an irregulär chromatin 

 network can be distinguished, each also possesses a Single nucleole. 

 The oviduct passes forward from tlie ovaiy for a short distance 

 and joins the receptaculum seminis, receiving Laueer's canal, a long, 

 narrow tube the external opening of which is dorsal (Fig. 10). 

 From this point the tube passes through the sliell gland which lies 

 a little to the right of the median line. Specimens containing but 

 few eggs have the uterus confined to a space between the intestinal 

 caeca oii the sides, the acetabulum in front and the ovary behind. 

 When, however, the eggs have increased greatly in number the 

 outline of the uterus becomes lost and it nearly tills the posterior 

 three-fiuarters of the fluke (Fig. 14). The vagina enters the genital 

 sinus just posterior to the opening of the ductus ejaculatorius. 



