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Transactions of the Boyal Society of South Africa. 
extends through xvii and xviii into the anterior portion of xix. The 
ascending or vertical hmb of the spermatheca of one side extends from 
the posterior limits of xix, where it is dorsal to the alimentary canal to 
the septum separating xviii and xix, where it passes into the ventral 
chamber in xix. The ascending portion of the spermatheca of the other 
side lies entirely in xviii, and that part of it which is dorsal to the 
alimentary canal passes downwards to join the ventral chamber imme- 
diately in front of the septum separating segments xviii and xix. 
The wall of the anterior part of the spermathecal duct in the region 
of the pore is peculiar in that the anterior wall is peculiarly thickened and 
glandular. This thickening, which is composed of elongate columnar cells, 
is nothing more than a continuation of the clitellar epidermis. Strangely 
enough, although the clitellar tissue is still well developed behind the 
position of the pore, the posterior wall of the duct is thin and non- 
glandular, being composed of a flattened epithelium with spherical nuclei. 
In longitudinal sections the anterior part of the duct, cut somewhat 
obliquely, is plano-convex, the posterior side being straight, the anterior 
side concavo-convex, with the conv3xity directed downwards and forwards. 
Surrounding the epithelium of this part of the duct is an indistinct 
musculature. Behind this region the duct is very line and composed of 
an epithelium of cuneate cells (about eight appear in a transverse section) 
compactly arranged and with ovoid nuclei. External to the epithelium 
is a thin highly refringent yet indistinct layer, as seen in transverse 
sections. This layer when seen in tangential sections of the wall has a> 
striated appearance, and even in transverse sections of the duct there is an 
appearance of striation in the outer portions of the epithelial cells. The 
lumen of the duct is very minute, and particularly in the xvith segment, 
where the spermathecal duct turns on itself, the structure appears 
markedly striated and rigid. After turning on itself the lumen increases 
greatly in size, and the whole structure becomes greatly expanded. 
Further, the cells of the epithelium become very much larger and resemble 
in appearance the cells of the spermathecal gland, the protoplasm be- 
coming vacuolated and the spherical nuclei losing their central position 
which they occupy in the narrower portion of the duct, and becoming situ- 
ated towards the outer portion of the cells. This terminal portion situated 
in the posterior region of segment xvi appears as a globular dilatation. It 
passes backwards to join the ampullae of the spermathecae. The anterior 
portion of the ampullae merges histologically into the sac. The posterior 
portion has its wall composed of a flattened epithelium with spherical 
nuclei. 
Male Organs. — A pair of testes is present in xi, attached to the 
posterior surface of the anterior septum. 
Segments ix, x, xi, xii, xiii and xiv contain large masses of sperma- 
