TWO NEW MAMMALIAN CESTODES. 493 
extremity. In this respect this species differs from C. pectinata, 
where the testes are described as persisting to the last proglottis. 
It is noteworthy that in this species at the tapering posterior 
extremity no genital glands are observed in the last 12-15 
segments (figs. 13 & 15). 
Female Reproductive Organs. 
These appear earlier than those of the male. The first rudiments 
of the genital glands are found in the segments immediately 
behind the head (fig. 3). ‘The vagina opens to the exterior up to 
_ the 25th segment, but after that aborts from without inwards. The 
receptaculum is prominent from the first and persists throughout 
the strobila, except in the last 12-15 segments where, as already 
mentioned, no genital glands are observed. The ovary is rudi- 
mentary up to about the 40th segment, where it takes on its mature 
form, and at about the 50th segment the first traces of the uteri 
are seen. After the 100th segment all of the female organs 
except the uterus begin to atrophy, and in the posterior segments 
only the uterus and receptaculum seminis persist (figs. 12 & 14). 
The vagina, only complete in the early segments, runs out ventral 
to the cirrus-pouch and opens into the genital atrium posterior to 
cirrus (fig. 6). At its distal end the lumen is very small and the 
cuticular lining very thick. In the region beneath the cirrus-pouch 
it is surrounded by deeply staining cells as in C. variabilis Stiles 
(21), and in this region has numerous bristles on its walls. It is 
a straight tube, and runs in to open into the large receptaculum 
seminis. The receptaculum seminis is elongate, °2 mm. long by 
‘1 mm. broad. It is surrounded by a thin layer of circular muscle- 
fibres, and outside the fibres is a single layer of cells which stain 
deeply. The ovary consists of anumber of ‘“ Indian club” shaped 
pouches. Each pouch opens into a common reservoir by a narrow 
neck (fig. 10). The oviduct runs from the reservoir of the ovary 
towards the yolk-gland. Beyond the opening of the vitelline 
duct into the oviduct, the latter passes through the shell-gland 
and enters the uterus at a spot situated just below the ovary. 
The ovary is situated dorsal to the receptaculum. Its outer 
tubules overlap the receptaculum, but the inner tubules are 
slightly nearer the median field. Ventral to the ovary and near 
the posterior margin of the segment is the small vitelline gland. 
Alongside it, towards the median field, is the comparatively large 
shell-gland (fig. 11). The duct from the receptaculum seminis 
opens into the reservoir of the ovary at the side nearer the 
margin. 
The uterus is formed dorsal to the ovary. The female genitalia 
are crowded close together. The uteri, at first separate, gradually 
extend towards the median field, and their blind ends become 
closely applied, so that in older segments it is difficult to distin- 
guish two uteri. The uterus does not cross the longitudinal 
canals and nerves, but in older segments pushes them nearer the 
