Occasional Papers of the Museum of Zoology 3 



The two suckers are well developed. The anterior one is 

 situated ventrally at the edge of the anterior margin. It is smaller 

 than the posterior sucker, although it often appears larger on 

 account of the protrusion of the surrounding body wall. In some 

 specimens this anterior sucker was in a protruded state, and in 

 others it was drawn down into the body so that it touched the 

 pharynx. The acetabulum is situated ventrally in median line 

 about one-third the length of the body from anterior end. This 

 sucker is deep and has a large triangular opening, around which 

 there is a thick muscular investment. 



The digestive system consists of an oral sucker, pharynx, and 

 two simple intestinal branches. The latter extend to the posterior 

 part of the body where they end blindly. Although these coeca 

 remain simple, they become much sacculated by numerous folds; 

 especially in the region from the acetabulum to posterior testes 

 these folds are much more complex. 



An excretory pore at the extreme posterior portion of the body 

 is connected with a reservoir-like region from which there are two 

 main lateral branchings. These lateral branches extend forward, 

 taking somewhat the same position as the branches of the intestinal 

 coeca. These excretory branches cannot be traced in toto mounts, 

 but in serial cross-sections the main lateral branches could be 

 followed from caudal reservoir about half the length of the body — 

 almost to the acetabulum. There seem to be many side branches 

 from the main canals but the network is so delicate that it could 

 not be followed. 



The two large lobate testes are connected to a coiled cirrus by 

 vasa efferentia. The testes are divided distinctly into three lobes 

 situated in mid-line in the posterior third of the body. The vasa 

 efferentia could be seen only at the point where they entered the 

 cirrus sac. The cirrus sac is about half as large as one testis and 

 has very thin walls. Within the walls of the cirrus sac there is a 

 complicated tubular arrangement by which spermatozoa are 



