1907.] WORMS OF THE FAMILY EUDRILID^. 425 



fication of the integument in its neighbourhood. On the xivth 

 segment are the paired orifices of the ovidtccts. These lie exactly 

 behind the nephridiopores of that segment and not far from the 

 posterior boundary of the xivth segment. The apertures ai-e quite 

 conspicuous, but not much (if at all) larger than the nephridio- 

 pores upon the clitellum, which, as already mentioned, are wider 

 than are those apertures upon the segments in fiont of the clitellum. 



The onale pore is a single aperture like the spermathecal pore. 

 It lies exactly on the boundary-line of segments xvii. and xviii. 

 It is considerably laig-er than the spermathecal pore, and the 

 actual orifice is surrounded by an area having a rather transparent 

 appearance. There is no protrusion of the Bursa propulsoria., nor 

 is the orifice situated upon an area which is at all raised beyond 

 the general level of the body. Apart from the slightly modified 

 integument surrounding the male pore, which has no counterpart 

 in the case of the spermathecal pore, the body of this species shows 

 oio genital p)ci2nllce. 



With regard to internal structures I have no observations to 

 make, save those based upon examination with a lens and a micro- 

 scope in the case of detached pieces of certain oi-gans and systems. 

 I have not investigated this Eudrilid by means of sections on 

 account of its poor state of preservation. 



With regard to the alimentary tract, the paired calciferous 

 glands seem to me to be rather further back than the thirteenth 

 segment, but as the worm was much softened I should not like 

 to be quite certain. The condition of the proximal swellings 

 upon the sperm-ducts seems in this genus to offer systematic 

 characters for the differentiation of the species. For in iV. tenuis 

 these " Samenmagazine " are hardly marked at all, and they 

 are quite conspicuous in iV. svjihonochceta. In the present 

 species these structures are jDresent, but rather different in 

 their condition from those of some other Eudrilidte. Each of 

 these swellings upon the sperm-duct is of oval form, tapering 

 towards each end ; but instead of lying immediately after the 

 funnel of the sperm- duct, there is a considerable stretch of narrow- 

 tubular sperm-duct before the funnel. The latter lies deep within 

 the sperm-sac. I have observed the characters of these bodies in 

 the smaller specimens, not in that whose structure has served 

 for the preparation of the rest of the present description of the 

 species. 



The terminal male e^erent apparatus is constituted as follows : — • 

 Each of the two prostate or spermiducal glands measured about 

 10 mm. in length, and each gland was folded only once ujDon 

 itself, thus forming a U. The diameter of each gland was not 

 more than, if indeed quite so much as, 1 mm. The (morpho- 

 logically) posterior end of each gland lay further forwards in the 

 body than the proximal or anterior end of each spermiducal 

 gland. Anteriorly each tubular spermiducal gland suddenly 

 narrowed to form a firm and slender due'.; ; the two ducts running 

 backwards soon join and form an unpaired tube which constitutes 



