OLIGOCHATA OF TROPICAL EASTERN AFRICA. 215 
developed upon the ventral surface of the body; the segments 
of which it is composed are a little difficult to map on account 
of the fact that the segments are subdivided by numerous 
transverse furrows, which do not correspond to the actual 
segments themselves. The arrangement is shown in the 
accompanying figure (fig. 10). Behind the median spermato- 
thecal pore, which lies upon the 13th segment, there is a 
furrow which is the boundary line of Segments x111/xIv. 
This latter segment bears a median genital papilla of an oval 
form, the long axis of the papilla being disposed transversely ; 
in front of and behind this papilla is a short furrow ; then follow 
five other transverse furrows, the last of which marks the line 
between Segments xv1/xvit ; the clitellum is developed laterally 
in the region which is occupied by the various furrows which 
have been described; on the 16th segment is a pair of genital 
papillze, one on either side of the median line; behind the male 
pore is a single and median papilla upon the boundary line of 
Segments x1x/xx. 
The spermatothecal pore is upon the 13th segment ; it 
is very conspicuous, being borne upon a prominent projection, 
which is no doubt retractile. The male pore is even more 
conspicuous, and is of about the same area. 
The nephridia of this species appear on a dissection to be 
paired structures like those of other Eudrilide. This is, 
indeed, the case, but the duct leading to the exterior forms a 
network within the integument, as in the genus Libyodrilus, 
where I have lately described it.1 I have mainly studied 
the nephridial system of this worm in the anterior segments of 
the body ; in transverse sections through one of the anterior 
segments—the ninth, I think—two longitudinal ducts are 
observable running just to the inside of the longitudinal mus- 
cular layer in the peritoneum on each side of the body. These 
ducts correspond in position with the pairs of setz ; the inner 
of the two on each side is the larger. Near to the septum 
dividing the segment from the one in front the inner duct 
1 On the Structure of an Earthworm allied to Nemertodrilus, &c.,” 
‘Quart. Journ. Mier. Sci.,’ vol. xxxii, p. 553. 
