OLIGOCHHTA OF TROPICAL EASTERN AFRICA. 207 
vessel has valves at the points where it perforates each 
septum. 
The alimentary canal has a gizzard in Segment v1; the 
cesophagus has a number of pairs of peculiar glands, which 
are separately described in connection with those of other 
Eudrilids below. The intestine begins in Segment xv. The 
cesophagus is very vascular. 
The first septum separates Segments tv/v; it is very delicate; 
behind this are five very thick septa, and then follow two others 
which are somewhat thicker than those which follow them. 
The nephridia commence in Segment 1v. They appear to 
open in front of the ventral sete; in any case their duct was 
traced into the body-wall on a level with the ventral sete; but 
whether it expands into a plexus like that of Libyodrilus, or 
opens at once on to the exterior, I am unable to say; the 
nephridial duct is not a conspicuous sac, as in some other 
Eudrilide, but a tube having an intra-cellular duct. 
Reproductive organs.—This species has, as have the 
other species of the genus, only a single pair of testes; as is 
customary when there is but a single pair of these gonads, they 
lie in the 11th segment. Lach testis is attached to the front 
wall of Segment x1; its shape is a little unusual. The testis is 
a curved rod of narrow dimensions, only a little broader than 
elsewhere near to its origin from the septum; if it were to lie 
in a perfectly straight line in its segment, as the testes usually 
do, it would reach as far as the funnels of the sperm ducts ; it 
therefore has to be coiled in order to get it out of the way. 
The cells of which the testis are composed are not very distinct; 
the nuclei, however, are; these nuclei are larger and clearer at 
the base of the gonad. 
The sperm-sacs lie in Segment x11; they depend from the 
anterior septum of this segment; they are fused together at 
their origin, and the question therefore arises as to whether 
we are to consider that there are two sacs or only a single 
bifid sac. The latter view would bring the sperm-sacs into 
correspondence with other parts of the generative apparatus ; 
in any case they are not to be distinguished at their actual 
VOL. 36, PART 2.—NEW SER. P 
