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The glandular part of the prostate which commences at the anterior bend of 
the organ consists of two or possibly of three layers. The inner lining consists of only 
one layer of epithelial cells with ovoid nuclei. These long cells appear to be sur- 
rounded by a narrow zone of fibrous or perhaps muscular tissue with few nuclei. 
3ut by far the greatest part of the prostate consists of fibrous tissue with numerous 
small roundish nuclei, with here and there a cell being visible, and with a few cells 
of a glandular appearance (fig. 68), especially toward tie circumference. In cross- 
section the anterior part of this prostate is triangular in outline, while the muscular 
part is always circular, and in size always thicker. The very narrow part of the 
prostate which penetrates the body-wall is strongly muscular of the same general 
structure as the free muscular part. The general structure of the prostate appears 
similar to the one of Pontodrilus hesperidum as described by Beddard. He has 
pointed out the absence of a regular layer of glandular cells in the prostate of that 
species, and it is possible that this construction of this organ which thus ap- 
proaches that of Ocnerodrilide, is not a species but a generic character, if it does not 
prove to be of even greater value. 
Vascular system. There are a dorsal and ventral vessel, but no subneural, nor 
any subintestinal vessel, and no thyphlosole. The two main vessels are connected 
with hearts in x, xi, xii, xiii, the most posterior one of which is found in somite xiii, 
immediately in front of the sacculated intestine. ‘This heart is the largest, the others 
gradually decrease in size forward. The posterior part of these vessels are entirely 
free of brown cells. The ventral vessel is forked in somite ix in two parallel 
lateral vessels, there being no central vessel left. These two branches are always of 
unequal size, both being situated immediately under the cesophagus (fig. 64 7. ».) In 
the somites anterior to x, these branches of the ventral are connected by laterals with 
the dorsal vessel. In one specimen the ventral fork commenced in xii (fig. 64). 
Between the dorsal vessel and the ventral forks there are connecting vessels, 
one pair in each of the somites y, vi, vii, vili and ix. To the ventral parts of these 
connecting vessels are attached oblong glands, which again are surrounded by a coat- 
ing of globular brown cells. These glands do not extend clear to the dorsal vessel, 
but end laterally before reaching it. The nature of the glandular cells appear the 
same as those of the pharynx, staining in exactly the same way. The cells of these 
septal glands are more numerous in the anterior somites, gradually diminishing 
posteriorly, while the opposite is the case with the free round cells which are more 
numerous in the posterior glands (figs. 29 g/. and 71 g/.) 
Nephridia (figs. 71 and 72). These organs commence in somite xiii, or in the 
same somite as the ovaries. The first two anterior nephridia are furnished with a 
smaller covering of peritoneal cells, but already in xvi do the nephridia attain their 
full size, as in all posterior somites. 
The nephridia are built upon the same general principles as those of Argilo- 
philus, Deltania, Oenerodrilus and Pheenicodrilus, as well as of Lumbricus as shown 
by Benham. We find here the corresponding ducts, canals, lobes, ete., and a gen- 
