1907.] WORMS OF THE FAMILY EUDRILID.E. 417 



conspicuous in this as in the next species. The spermiducal 

 glands are peculiar in form and do not altogether agree with those 

 of F. sylvestris, to which they appear to come nearer in structure 

 than to those of other species of the genusFoli/to7'eutus. They agree, 

 however, with the last-named species in the fact that the duct of 

 the gland instead of emerging, as is the rule among these worms, 

 from the end of the spermiducal gland, leaves the gland some 

 little way in front of the proximal end. Each gland is rather 

 bent in form, but otherwise lies straight. It is of firm consistency, 

 but is not covered with a sheath of muscle appi-eciable to the naked 

 eye or through a lens. The slight bending of the corresponding 

 glands in Polytoreuius sylvestris figured by Michaelsen is rather 

 exaggerated in the present species. They appear also to be rather 

 longer in P. sylvestris than in P. ruivenzorii. Michaelsen does 

 not mention in that species a character which is very noteworthy 

 in P. 7'icwenzorii. He describes the " prostate " glands indeed 

 merely as being " unregelmiissig eingeschniirte." In the specimen 

 of P. rioivenzorii reported upon hei-e the surface of the gland was 

 much marked by furrows, and the appearance given was that of a 

 very long gland tightly coiled up with 'some concrescence between 

 the individual loops of the coil. There is no indication of any- 

 thing of the kind in the figures given by Michaelsen either of 

 P. sylvestris or of its allies. The two copulatory chambers 

 mentioned by Michaelsen * in P. sylvestris and P. Mrvmaensis are 

 quite as large in P. ruwenzorii as in those species. 



As in several species — for example, Polytoreutus kirimaensis t, — 

 the present species of Polytoreutus is to be characterised by a 

 very slender sj^ermathecal sac which lies beneath the nerve-cord, 

 than which it is no thicker. It is thus diiiicult to see, and, as 

 Michaelsen has remarked, is apt to escape the eye. Particularly 

 was this the case with the worm described in the present 

 communication. For the contents were very slight in certain 

 regions of the sac, which rendered it even more diflicult of obser- 

 vation. It is certainly no wider than the nerve-cord, which 

 overlies it. It is largely by virtue of the difliferent forms which 

 the spermathecal sac shows in this genus that the species of 

 Polytoreutus are discriminated. 



The species which I name Polytoreutus ruwenzorii is Cjuite 

 different in details, so far as concerns this organ, from any other 

 species of which descriptions have been jjublished. It comes 

 nearest to Polytoreutus % kirimaensis so far as I can gather, but 

 shows obvious differences from that species. 



The median spermathecal sac is slender as in that species 

 and is straight or nearly so in its course beneath the nerve-cord, 

 not much convoluted as in the allied Polytoreutus sylvestris §. 



* Loc. cit. 



t Micliaelseu, " Die Regeuwlirmer Ost-Afrikas," in Deutsch-Ost-Afrika, vol. iv. 

 1896, p. 16. t J^oc. cit. pi. ii. fig. 21. 



§ Where, however, it is also occasionally less convoluted, perhaps in less mature 

 individuals (Michaelseii, loc. cit. pl.ii. fig. 23). 



