PARASITES FROM THE SOCIETY'S GARDENS. 143 
from the male but immediately behind it. The cirrus-pouch 
contains a highly convoluted vesicula seminalis, a short pars pro- 
Statica, and a long straight ductus and cirrus. The musculature 
of the pouch and of the cirrus is extremely well developed. 
The anterior testis lies on the left side, near the genital 
aperture. ‘The second testis lies on the other side of the body, 
and is separated from the first by the uterus. The anterior border 
of the one is about ‘2 mm. in front of that of the other. Both 
are somewhat elongated oval in outline, their long diameter 
measuring *5—65 mm. ‘They are moderately thick and are not 
much overlapped by the uterus. 
The ovary lies not far behind the ventral sucker, alongside the 
proximal end of the cirrus-pouch. It is globular and considerably 
smaller than the testes. It is usually difficult to see, owing to 
its being obscured by the uterus. Laurer’s canal is present, but 
there is no receptaculum seminis. he initial part of the uterus 
is filled with sperms. The yolk-glands havean unusual disposition. 
Instead of being lateral they are entirely dorsal. Situated in 
the posterior half of the body, they extend from the level of the 
genital aperture to a short distance (‘4 mm.) behind the testes. 
They consist of fairly large follicles which le between the ex- 
eretory vesicle and the cuticle, and which do not spread to the 
outer side of the intestinal diverticula. 
Starting from the ovary, the uterus forms several small dorsal 
convolutions on its way towards the posterior end of the body. 
On turning forward it becomes greatly dilated. At first it runs 
almost straight forwards, then bends towards the left testis. 
Passing between the testes it forms a fairly large convolution in 
front of the right testis. It then passes across the ventral sucker 
and finally runs down along the left side of the cirrus-pouch. It 
overlaps the intestinal diverticula to a considerable extent. The 
vagina is a wide muscular structure about half the length of the 
cirrus-pouch. The ova are very numerous, dark brown in colour, 
and measure *020—:023 x :013—014 mm. 
This species is most closely allied to Opisthogonimus philo- 
dryochus West, but it appears to present features of sufticient 
importance to warrant its being regarded as the type of a distinct 
genus. The chief distinctive features are the position of the 
genital aperture, the shape and structure of the cirrus-pouch, and 
the position of the yolk-glands. 
4, OPISTHIOGLYPHE ADULESCENS, sp.n. (PI. I. fig. 3.) 
A few specimens of this form were taken from the intestine of 
an Asp Viper (Vipera aspis). They were all obviously immature, 
and on that account the following can only be regarded as a 
provisional description. For the same reason it is impossible to 
be absolutely certain that this form is distinct from the already 
known species of the genus, but one or two distinctive features 
seem to point to the fact that it is a separate species. 
