4 ARTHUR E. SHIPLEY. 
are rather more rounded than those of the other two species, and some have more 
pointed ends. The egg-shell is thick, with two clearly-defined contours. 
The yolk-glands are easily recognised by their brown and glistening appearance. 
Like the testes they are scattered, but they lie more superficially than the latter. 
Although there is little differentiation between the medullary and the cortical regions, it 
is plain that the yolk-glands lie in the cortex and the testes in the medulla. 
The epithelium of this Cestode consists of unusually large cells, somewhat 
columnar in shape, with their square outer ends pressed against the cuticle, and their 
inner ends tapering (fig. 7). Their nuclei lie about, but not quite at, the same level, 
near the inner end. 
The parenchyma is loose and stains but slightly, it is traversed by but few muscle 
fibres. The single pair of longitudinal excretory canals are conspicuous in sections, and 
so are the nerve trunks. ‘There are numerous small excretory tubules running just 
below the external epithelium. 
I have ventured to dedicate this species to Captain Scott, the distinguished 
commander of the Antarctic Expedition, though I am well aware that there is a certain 
delicacy in doing so. Some people have a horror of Cestodes, and do not care to have 
their names associated with them. ; 
Dibothriocephalus scottiLeneth of specimens 9cem. and under ; number of pro- 
elottides about 140; head rounded, diameter Imm.; average width of middle 
proglottides about 2mm.; very short neck. Posterior edges of proglottides stand 
out, but do not appreciably overlap the anterior end of succeeding proglottis ; uterus 
spacious, with a few diverticula, not a rosette ; ova 0°04 by 0°03mm., with thick shell. 
DIBOTHRIOCEPHALUS WILSONI. 
This is a very attractive little tapeworm of few proglottides, which I have ventured 
to dedicate to my friend Mr. E. A. Wilson, M.B., who was both a doctor and a zoologist 
in the ‘Discovery. It somewhat resembles Krabhe’s Dibothriocephalus lanceolatus, 
from Phoca barbata, but is much smaller. 
The length varies from 4 to 5:5mm. In the larger forms the greatest breadth is 
Imm., this occurs in the region of the last segment but one, or perhaps two. The 
breadth of the head is a little less than 0°5mm., and its greatest length is about the 
same. 
The number of the proglottides varies from nine to thirteen or fourteen. There is no 
neck, the first proglottis lying close to the head. The proglottides gradually widen until 
they reach a breadth of Imm., and in this region are somewhat crumpled (fig. 8). 
The last proglottis is shaped like a truncated cone, rather indented at the hinder 
narrower end. The hinder edges of the proglottis only slightly overlap the anterior 
edge of the following proglottis; they are in all cases but the last wider than the 
