TWO NEW SPECIES OF CESTODES. 273 
for certain reasons (geographical distribution and host) to be 
compared particularly with that which forms the subject of the 
present communication. In these two species the testes are 
entirely posterior to the female gonads. It seems possible that 
some differences are to be accounted for by the state of contraction 
of the proglottids. 
In Oochoristica marmose, in those proglottids where they 
are at the height of their development, the testes are mainly 
to be found at the sides of the centrally placed ovary and vitelline 
gland, which are themselves very large and occupy most of the 
central region of the proglottid, both dorso-ventrally and antero- 
posteriorly. The testes extend above the female gonads dorsally, 
and there is a single row of them posteriorly behind the vitelline 
gland—in fact, they occupy pretty well all of the available space 
within the proglottid. They are numerous—TI have counted 
as many as 50 in a single horizontal section. Inasmuch as a 
single proglottid cut horizontally was displayed in 25 sections 
(not including sections through the cortex), the number of testes 
is obviously large, even though the first and last sections only 
show one or two testes. The largest number given by Zschokke 
in his review of the genus is 100 for O. rostellata. My species 
must considerably exceed that. 
The vas deferens opens through the cirrus-sae into a genital 
cloaca, The genital cloaca is less conspicuous in this Oochoristica 
than it is in some other tapeworms. It is in depth about one- 
third of the length of the cirrus-sac, which is itself small, and 
has no marked specialization into regions such as occurs, for 
example, in Hugonodeum adicnemni*. It is narrow and tubular 
in horizontal section, and the cirrus-sac opens into it at its internal 
extremity. It is surrounded by muscle-fibres, which doubtless 
act as a sphincter. ‘This orifice is in front of that of the vagina. 
The cirrus-sac is small and only extends back as far as the nerve- 
cord. It is as usual bottle-shaped, being wider posteriorly, where 
also the muscular wall is much thinner. I could discover no 
spines upon the contained cirrus, which widens out and becomes 
very muscular at its outer end. Altogether there is nothing 
remarkable about the cirrus-sac and cirrus of this Oochoristice. 
But its shape and size and the muscularity of its walls are 
important specific marks—for they differentiate it from 
O. rostellata. 
The vas deferens issues from the cirrus-sac as a straight tube 
running parallel with the vagina. Later it forms a loose and 
not very extensive coil, and often bends backwards and breaks 
up into a number of branches, which again become subdivided 
to supply the individual testes. This region of the sperm-duct 
is of the nature of a network, for anastomoses exist between 
many of the branches. The walls of the finer branches of the 
sperm-duct and their communication are quite visible, even 
* P.Z.S. 1913, p. 866, text-fig, 144. 
