new African Earthworm. 459 



is situated near the stalk-end of the cell. In the middle 

 chamber the cells (tig-. 5, b) are much taller and narrower, 

 and have a very short "cup" at the free end, a much 

 narrower stalk, and a smaller nucleus, situated further from 

 the basement-membrane. 



The sperm-containing diverticula (figs. 3 & 4, Div.), 

 varying in number from one to three, which project on the 

 anterior and outer surface of the organ, open into the cavity 

 of the middle chamber by a narrow passage a little above its 

 junction with the muscular duct. When more than one of 

 these diverticula or pockets are present, their ducts appear 

 to unite into a single canal of small calibre. There is a 

 muscular coat external to the epithelium lining the pockets, 

 which probably serves for the expulsion of the sperm at the 

 appropriate moment. 



The pockets and their ducts, like the rest of the sperma- 

 theca, are lined with a glandular epithelium, the cells of 

 which are similar to those of the middle chamber, but 

 smaller. The contained sperm is inassed together into a 

 solid ball — so much so that, on teasing out the mass of 

 sperm from the pocket, I at first imagined that it was 

 enclosed in a membrane. On the examination of sections, 

 however, this does not appear to be the case. It is probable 

 that the spermatozoa were swimming in a fluid medium, 

 which has become solid as the result of preservation. 

 Possibly it is the function of the cells of the epithelium to 

 produce a special fluid for the nutriment of the spermatozoa 

 during their retention in the pocket. If they were " glued " 

 together, in the manner described, during life, it is difficult 

 to understand how they could ever escape from the pockets 

 again, since the way of egress is so narrow. 



The muscular duct of the spermatheca seems invariably to 

 contain a tough cuticular lining of peculiar shape. This is, 

 in fact, the lower, trumpet-shaped portion (fig. 6, T.) of the 

 "• spermatophore," and is almost exactly like that described 

 by Beddard in the case of D. austeni. To the more detailed 

 study of this portion of the apparatus I shall return later. 

 The upper part of the spermatophore consists of a spherical 

 capsule (fig. 6, Cap.) of a fibrous or parchment-like con- 

 sistency, which "when fully developed occupies the middle 

 chamber of the spermatheca, and fits into the trumpet- 

 shaped upper end of the cuticular tube. This capsule and 

 the trumpet-shaped tube together make up the complete 

 11 spermatophore.*" 



The wall of the upper capsule is composed of numerous 

 layers of some substance which is apparently non-cellular 



