92 MR. F. E. BEDDARD 0\ THE [June 3, 



shows that a tube of feeble diixiensions and with a thick muscular 

 coating nearly reaches the exterior at a point not far off the lateral 

 setfe of that segment. This tube actually joerforates the body- wall 

 for a certain (short) distance, and is undoubtedly the tube which 

 afterwards opens at the same s]3ot, and has been regarded as the 

 narrower, distal, part of the spermathecal sac. Traced in the oppo- 

 site direction, this tube approaches the thickened sejDtum which 

 separates segments xiv./xiii. It enters into the thickness of that 

 septum and travei'ses it obliquely and dorsally in direction. At 

 or about the middle of the septum the tube gives off a branch, or 

 is joined by another tube, which also passes obliquely through the 

 septum and in a short straight course. The dii'ection is, however, 

 back again towai'ds the lumen of segment xiv. This second tube 

 ends in a smallish i-ounded body, whose interior is divided up by 

 trabeculse, and which is plainly the receptaculum ovorum or egg- 

 sac. It seems to be cleai-, therefore, that the two tubes together 

 constitute the oviduct of the mature worm which, as is well 

 known, opens into the egg-sac. But in this case, we should have 

 the anomaly of the oviduct being connected with the egg-sac 

 alone, as indeed Eisen states to be the case in the sexually 

 mature worm. The anomaly, however, does not exist. The two 

 tubes that we have been just considering open almost immediately, 

 after their junction the one with the other, into the cavity of the 

 xiiith segment in common with a sac which extends dorsally, as 

 well as ventrally, for a short distance. It might be said, indeed, 

 that the mouth of the two tubes is rather into the sac, which 

 then, in its turn, opens into the coelom of segment xiii. At the 

 point of opening, the columnar epithelium lining the tube becomes 

 moi'e pronouncerl, and this region may be looked upon as the funnel 

 of the oviduct. In fact, we have in the immatui'e worm an oviduct 

 which opens into the xiiith segment on the one hand, and on to 

 the exterior on the other, a branch being given off to the egg-sac 

 on the way from the internal to the external orifice. The genus 

 Uudrilus, therefore, is not exceptional among Eudrilidpe ; the 

 oviduct, as in at least many genera^ \ communicates with the 

 exterior by a poi-e on the xivth segment quite independently of 

 the spermathecal sac ; at the other end it divides into two tubes, 

 one of which oj)ens by a funnel into the egg-sac, the other by 

 another funnel into a part of the system of sacs involving the 

 ovary. This statement of course lefers to the adult worm, in 

 which the speimathecal sac is closed from the body-cavity. The 

 spermathecal sac thei-efore of this genus is, as in othei- Eudi-ilidae, 

 a part of the egg-conducting apparatus, here simpler than else- 

 where. The spermathecal sac has no orifice of its own to the 

 exterior : it merely opens indirectly through the medium of 

 the oviduct, just as do the sacs involving the ovaries in the genus 

 Stuhlmannia^. But in the last-mentioned genus there is, in 

 addition, an entirely independent orifice of the system of egg- 



1 See Beddard, P. Z. S. 1901, vol. i. p. 354. 



2 Beddard, loc. cit. 



