700 Dll. F. E. BEDDAIIU OX 



allegeil to be of this genus. So iuiportaut in classilication is the 

 condition of the uterus that little doubt, 1 fancy, will be felt in 

 this matter. 



II. Description o/Cotugnia niai-gareta, sp. n. 



Thq genus Cotugnia is usually regarded as of the family 

 Davaineidfe, from all the other genera of which it differs by 

 the possession of a double sexual apparatus in each proglottid. 

 The only other character of importance which, so far as is 

 already known, serves to separate Cotugnia from other Davai- 

 neidfe, is the coniplicated and Acoleid-like disposition of the 

 lon"-itudina.l muscle-layer. The examination of examples of a 

 species of this genus from the gu,t of Caccabis onelanocephala 

 enables me to aild to our knowledge of the genus and to describe 

 a new species thereof. 



A large number of examples of this worm occurred in the 

 Caccabis in company with an Ilymenolepis, which is either 

 identical with, oi- at the least very closely allied to, Hymenolepis 

 vlllosa (known from Rustai'ds). I did not find it associated 

 (except for the doubtful case of one individual) with Rhabdo- 

 ■metra ci/Undrica, a parasite from the same species of Caccabis, 

 which I have lately described in these ' Proceedings '*. 



The extreme length of the woi-ni is about Sg inches, and it is 

 rather broad, measuring 3'5 mm. The segments are not long 

 and never as long as they are broad. The scolex is 1 mm. or a 

 little less in breadth ; it is followed by a strobila, which is at 

 first of equal breadth, and in which the segmentation is visible 

 at once. There is, at any rate, no long and well-marked neck. 

 The suckers are large and unarmed, and demand no special 

 description. 



The rostelluni of this species shows some interesting characters. 

 In examining the living worm fresh from the body of its host, 

 the rostelluu) is not at all obviou,s. It is apparently represented 

 by a mere dimple much smaller in extent than the large suckei's. 

 The conditions, indeed, reminded me of certain Ichthyota?niid9e, 

 where the rostelhim is repi-esented by little more than an apical 

 pit. In one s})eoimen which I thus examined there Avas this 

 dimple alone ; in another, however, a fringe of minute hooks 

 encircled the pit. These hooks are in a double row and of the 

 Dava.ineid pattern. In a third specimen, examined after preser- 

 vation in alcohol and glycerine, the apical pit is quite obvious and 

 encircled by a row of hooks arranged in a double series, which 

 is dumbbell-shaped, beiag of less dianaeter in the middle. The 

 whole area surrounded by the hooks is very much less in extent 

 tha,n that of the suckers. 



The smallness of the area occupied by the rostellum in this 

 species is the first point to which I wish to direct attention. 



* I'.Z.S. 1914, p. 859. 



i 



