STUDIES ON THE ECTOTAliASITIC TKEMATODES OF JAPAN. 131 



the others. In Mlcrocotijlc und Axinc it arisess from the oviduct 

 opposite, or at a short distance from, the point ^vhere this receives 

 the unpaired yolk-duct, in some species more towards the ovary and 

 in others more away from it ; it then proceeds toward the right 

 of the l)ody and also more or less forwards, and finally opens 

 into the right trunk of the intestine. In DicUdopliom (PL X, 

 figs. 1, 5, & 9) it does nearly the same, Ijut its origin is always 

 at a short distance towards the ovary from tlie point of union 

 of the unpaired yolk-duct with the oviduct. In OdocotijU the 

 genito-intestinal canal opens into the oviduct side by side with 

 the unpaired yolk-duct, proceeds on the right side fu* towards 

 the anterior part of the body, and finally opens into the right 

 intestinal trunk nearly on the same level with the point of union 

 of the paired yolk-ducts (I?l. IX, figs. 1, 7, & 11). In all the 

 2:enera hitherto mentioned the canal is almost straiiiht or makes 

 only a slight winding or two. In Oncliocolijlc it arises from 

 the oviduct at the point Avhere this bends backwards towards 

 the ootyp and where from one side the neck of the seminal 

 receptacle and from the other the median yolk-duct opens into 

 the oviduct. It then ])roceeds for some distance towards the right 

 side of the body, then Ijends backwards, making a few additional 

 windings on the way, and opens at last into the intestinal trunk 

 of the right side. It is, as I have stated elsewhere, the Laurer's 

 canal of Taschenberg,'^ which he represents as being on the 

 left side of the body and as opening to the exterior on the ventral 

 surface. But I have carefully followed it in seri-d sections and could 

 distinctly perceive its opening into the intestine; while as to its 

 position in the body, one must not rely on the posterior suckers hv 

 orientation, in tliis case ; for, as I have already stated, these are situat- 



1). Tasclieuberg— Weitere Beiträge, p. 22. 



