274 FRANK K. BEDDARD. 



principal facts which lead me to doubt the justice of includ- 

 ing this worm in either of those genera ; and, as will be seen 

 presently; there are other points, in the structure of the repro- 

 ductive organs, that are at variance with that view of the sys- 

 tematic position of the species. 



There are two pairs of testes attached to the anterior wall 

 of Segments 10 and 11. The testes of the 11th segment are 

 enclosed within the sperm-sac of that segment; the testes of 

 Segment 10 are also enclosed in a sac, which also includes the 

 dilated end of the sperm-duct. The sperm-ducts, as in so 

 many Eudrilidse, widen out just before opening by its funnel 

 into the interior of the sperm-sac ; furthermore the funnel is 

 placed a segment behind that which it ordinarily occupies; 

 this is so in many Eudrilidse. The sperm-duct thus perfo- 

 rates the septum twice before opening into the coelom ; the 

 facts are now so well known that I need not enter into the 

 matter at length. The two atria open by a common pore 

 upon the border line between Segments 17 — 18; they have 

 the usual tubular form, and the sperm-ducts open into them 

 considerably in front of their external orifices. 



The female reproductive organs (fig. 26) are somewhat inter- 

 mediate between those of Heliodrilus and those of Para- 

 drilus ; the ovaries, as in both genera, are each enclosed in a 

 sac attached to the front wall of Segment 13. The stalk of this 

 sac lodges the tube of the nephridium as it passes towards the 

 funnel ; the sac of each side runs forward and widens out to 

 form a dilated sac which partially involves the end of the ovi- 

 duct. From this dilated sac a narrow tube communicates 

 with a long spermatothecal sac ; the spermatothecal sac is 

 divided into two regions separated by a slight constriction. 

 At the constriction the lining of cells is much increased in 

 thickness, and seems to obliterate the lumen; the mass of 

 cells project for some distance into the anterior part of the 

 sac, which is narrower than the posterior part. There ap- 

 peared to be no actual connection between the lumina of the 

 two. The arrangement of this part of the spermatothecal sac 

 is on the principle of a lobster trap ; there is no facility for 



