SOME LITTORAL OLIGOCHATA OF THE CLYDE. 49 
shape, about as long as broad, and indented posteriorly. The ventral nerve-cord is 
characterised by the possession, through the whole of the anterior part of the body, of 
agoregations of cells in each segment which embrace the cord ventrally and laterally. 
These cells, though nowhere forming very prominent masses, correspond in appearance 
or copulatory glands of other 
p) 
with those which constitute the ‘“ Bauchmarkdriisen ’ 
forms. ‘They are mostly, in sections, pear-shaped or spindle-shaped, with very feebly 
staining, slightly granular protoplasm and deeply staining nucleus; they are of con- 
siderable size, and while they leave the dorsal side of the cord uncovered, frequently 
appear flattened over its sides and ventral surface, so as to give the appearance here of 
concentric layers. At the site of their occurrence the cord appears stalked in transverse 
section, being connected with the surface epithelium by prolongations of the cells. 
The testes are composed of six, seven, or more elongated club-shaped or pear-shaped 
masses on each side, springing from the ventral part of septem +2. Sperm morulz collect 
in segments x. and xi. The funnel is long, nine or ten times as long as broad; the 
length, however, varies, and may appear to be only about seven times the breadth ; 
the funnels are bent on themselves; the nuclei of the cells of which they are composed 
are, as usual, peripherally situated. The vas deferens is considerably coiled; it does 
not, however, extend backwards behind the clitellum ; in diameter it measures ‘(02 mm. 
There is a penal bulb of considerable size, its diameter being more than a quarter, 
nearly a third, of the diameter of the animal’s body; the bulb has a well-developed 
muscular covering; the cells of which it is mainly composed are much elongated, 
radially arranged, the nuclei being crowded together peripherally ; the lumen is almost 
central. 
Ova are found in segments xii. and xiii. 
The spermathece are characterised by a spindle-shaped ampulla which com- 
municates with the cesophagus; its external end is continued into the duct without 
evident demarcation. The duct is somewhat longer than the ampulla, and of about 
half the diameter of the latter; it is surrounded by prominent gland-cells round its 
external aperture. The epithelium of the ampulla is columnar, but of very irregular 
height ; the nuclei of the cells are much elongated. In the duct, the epithelium is 
lower, and the nuclei are spherical; the muscular coat of the duct is situated between 
and amongst the cells, the nuclei of the latter being all external to the muscular 
layer; in the ampulla the muscular coat is, however, quite external to the epithelium. 
Both ampulla and duct are lined by a thick cuticular coat, continuous at the orifice 
with the very thin cuticle of the body-surface. The prominent collection of gland- 
cells round the duct near its external aperture consists of the epithelium of the duct, 
here much elongated and extending outwards far beyond the muscular layer of the 
duct. 
The clitelluwm is only peculiar in that it dies away gradually in front, without any 
definite line of demarcation. 
Sporozow are present in the alimentary canal. 
