sTrroiEs ox the ectopabasitic teematodes of japax. ^31 



the others. In Microcottjle and Axine it arises from the -oviduct 

 opposite, or at a short distance from, the point where 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 body and also more or less forwards, and finally opens 

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

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

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

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

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

 the unpaired yolk-duct, proceeds on the right side far 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 (PI. IXj figs* 1, 7, & 11). In all the 

 genera hitherto mentioned the canal is almost straight or makes 

 only a slight winding or two. In Onclwcotijle it arises from- 

 the oviduct at the point where this bends backwards towards 

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

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

 the oviduct. It then proceeds for some distance towards the right 

 side of the body, then bends 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 serial 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 for 

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



1). Tasohenberg— Weitere Beitrage, p. 22. 



