1054 DR. F. E. BEDDARD ON 
and cannot be compared with spines such as I infer to exist in 
Shipleya. The last-mentioned genus does not appear to possess 
testes in the same segments as those which contain the ripe 
female sexual products; Fuhrmann did not see those gonads 
but presumed that they were to be found in earlier segments. 
Now in my species the testes are obvious and numerous in 
very many segments. Prof. Fuhrmann, with his experience 
of the structure of Cestodes, could not have missed them were 
they so plentifully present in Shipleya mermis. This is a 
most important difference between the two forms, and one 
which marks out the genus Shipleya as having retained to 
some extent the dicecious nature of its ally Diwococestus. There 
is no trace of such a state of affairs in my species. It is doubt- 
less of minor importance to point out that the receptaculum in 
Shipleya has a crenate outline and isa small sac, while in my 
species it is rather large and of circular contour. Also the 
vitelline gland of my species is displayed in the same horizontal 
section with the ovary, and therefore does not lie entirely dorsal 
to it, as is stated to be the case in Shipleya. Finally, it is rather 
remarkable that there should be so close a likeness between the 
uterus in the two forms. It has in both a nearly annular shape, 
being incomplete however on one side. The uterus persists in 
both species, and is not replaced by anything in the nature of a 
paruterine organ. This fact, coupled with the character of the 
female generative system, leads me to place my species in the 
neighbourhood of this genus Shipleya, but other details of 
anatomy forbid their reference to the same genus. 
The species described in this paper therefore differs from 
Shipleya in the following assemblage of characters :— 
(1) Lhe muscular layers of the body-wall are feeble. 
(2) There are no papille on the scolex and no apical depression. 
(3) The water-vascular tubes have no ramifications. 
(4) The testes are nuinerous in all segments until those in which 
the uterus is developed, and form rows right across the 
proglottids. 
(5) Although the vagina comes to be aborted it is fully developed 
in the most anterior segments, and there are traces of the 
terminal part for some way back in the shape of a sac 
opening on to the exterior in front of the cirrus. 
(6) The cirrus has no spines wpon it. 
(7) The uterus forms a network. 
(8) The vas deferens is dilated into a vesicula seminalis of 
peculiar form. 
As the definitions of genera among the Cestoidea go, these 
characters are, as it appears to me, quite sufficient to allow of 
generic separation. They are also accompanied by a few minor 
differences, such as the form of the receptaculum seminis, and 
also by some minor points of likeness, such as size and absence of 
neck and regular alternation in genital pores. 
