1901.] FROM BRITISH EAST AFKICA. 353 



tissue was uot uiucli iu amount, and 1 detected no ripe ova therein; 

 but there were cells far on the way to become ova. This gonad, 

 in fact, as always, contrasts with the testes, \Adiere the germinal 

 cells are loosened and float hito the spex'm-sacs before undergoing 

 much development. I direct attention to the diagrammatic sketch 

 (text-tig. 87, p. Sol) of the complicated female reproductive system 

 of' this Annelid, which has not been hgured. It will be noted that 

 the cells from tht^ ovary of the thirteenth segment have to travel an 

 exceedingly devious course to reach the receptacnlum ovorum, 

 where, according to current views, they complete their develop- 

 ment. The passage would have to be through the terminal atrium 

 to one of the circumcesophageal spermathecal sacs, and then 

 through one of the two ducts only leading thence to the recepta- 

 cnlum ovorum by way of the oviducal funnel. 



The alternative view is to suppose the transport of the ovarian 

 cells at a period before the spermathecal sacs are established. 

 But it is not easy to suppose that in such an immatm'e condition 

 the reproductive products would be sufficiently ripe ; and if they 

 were, why should so much be left behind ? I am disposed to 

 resume an hypothesis which I advanced some years ago \ and 

 which was stoutly combated by Dr. Horst -, but is accepted by 

 Dr. Eisen ', viz., that the contents of the receptacnlum ovorum are 

 an ovary, a second ovary belonging to the fourteenth segment 

 w hich has become evoh ed in the septal sac which is the recepta- 

 cnlum. At the time that Dr. Horst wrote, the existence of two 

 pairs of ovaries and ducts in the embryo Octocliwtus ^ was not 

 known, nor the double oviducts of Lumbriculus. These and a 

 few other examples show that there is no a priori objection to 

 two pairs of ovaries iu an Oligochfete. It is j^ermissible to attempt 

 to show a £irima facie case for the enquiry ; but I hope to bring 

 for\^"ard actual facts in support of the contention. Two ovaries 

 might exist without the presence of two pairs of oviducts ; but 

 it is not necessary to w^eaken the position by allowing only a 

 single oviduct which alone exists in Eudrilus, Stuhlmannia seems 

 to me to have the requisite two pairs of oviducts. The recepta- 

 cnlum ovorum has no cqmmunication with the body-cavity or 

 with the outside world except through the oviducal funnel ; this 

 is much plicated, and enters nearly every one, if not ail, of the 

 chambers into which the receptaculum is divided. Immediately 

 after the funnel narrows into the oviduct it divides into two 

 branches, neither of which is appreciably thicker than the other. 

 I can find no ■' Eitrichterblase," as Michaelsen terms it. As is 

 shown in the accompanying figure (text-fig. 87, p. 354), one branch 

 runs to the body-wall and opens upon the exterior in the xivth seg- 

 ment in the usual way that the oviducts of earthworms open. The 

 other branch has a rather longer course, and, passing fairly straight, 



1 P. Z. S. 1887, p. 376. 

 - Mem. Soc. Zool. France, 1890. 

 ^ Proc. Calif. Acad. Sci. ii. No. 2, 1900. 

 ' ' Beddard, Quart. Jouru. Micr. Sci. xxxiii. 



