52 DR. J. STEPHENSON ON 
from side to side, with many and irregular windings of the lumen. The duct is stout, 
and leads downwards from the posterior end of the body of the organ; in length it is 
about one-third of the post-septal. 
The cerebral ganglion is elongated, reaching as far as the level of the sete of 
seoment i. Its lateral margins diverge posteriorly, where it is indented at a blunt 
angle, as shown in Pl. I. fig. 9. The ventral nerve-cord shows small “ copulatory glands ” 
(Bauchmarkdriisen) in segments xiv. and xv. ; the cells of the glands embrace the cord 
laterally and ventrally, but not dorsally ; owing to the connection of these cells with 
the surface epithelium, the cord appears stalked in transverse sections at these situations ; 
there is externally a small transverse ridge opposite each gland. 
The testes are one on each side, in the usual position. The seminal funnels are 
four times as long as broad, of the usual cylindrical form, but a little narrower towards 
their attachment to the septum; the lumen is obvious in the living condition, and in 
sections is seen to be not central but nearer the inner side ; the margin of the internal 
aperture, where the spermatozoa enter the tube, is everted, so as to form a small true 
Fic. 9.—Nephridium of the same. 
funnel, of a single layer of low columnar cells, perched on the cylindrical structure that 
usually goes by the name of ‘funnel.’ The vas deferens is thin, ‘0075 mm. in diameter ; 
it is but little coiled, reaches back to the level of segment xii, and penetrates the 
penial gland nearer the outer than the inner side of the latter. The male aperture, in 
segment xii., consists of an invagination of the surface epithelium in a direction 
obliquely upwards and outwards (PI. II. fig. 10); this invagination, narrow from side to 
side, receives the end of the vas deferens, not at its upper extremity, but on its imner 
wall; the invagination and its immediate neighbourhood are covered by a distinct and 
fairly thick cuticle. The penal gland (PI. II. fig. 10) is a single ovoid mass on each 
side, consisting of much-elongated cells with nuclei near their internal ends; their 
external ends form the inner wall of the invagination previously referred to; the gland 
has a distinct though feeble muscular covering, and muscular strands pass obliquely 
upwards from its surface towards the lateral body-wall; other strands, passing over it 
obliquely from the ventral to the lateral body-wall, appear, so to speak, to bind it down. 
The spermathece consist of ampulla and duct, both of which present, especially in 
sections, a peculiar appearance, from the fact that the cells of which they are composed 
are irregular in size, shape, and disposition, and thus are very far from forming a regular 
