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 lirown and glistening appearance. 

 Like the testcs they are scattered, hut they lie more superficially 1han 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 testcs 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 1 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 scotti. Length of specimens 9cm. and under ; number of pro- 

 glottides about 140 ; head rounded, diameter 1mm. ; 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 O'Ooinm., 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 Krabbe's Dibothriocephalus Inncvnfiifux, 

 from Phoca barbata, but is much smaller. 



The length varies from 4 to 5 '5mm. In the larger forms the greatest breadth is 

 1mm., 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 1mm., 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 eases but the last wider than the 



