Entozoa from the yfurmun Coast. .'Sl.T 



present, uaiially in considerable numbers, in uU tlie eider- 

 ducks exiuniiu'd. 



An entire specimen meiisures 1 to 1^ cm. in lenj^tli, with a 

 maximum width of O'M mn). The seolex (fi;^. 8, A) is 

 flattened dorso-ventrally, and nie.-isiires 0"22-<>'27 mm. across 

 at tlie .suckers and about O'l/i mni. in thicknefls dorso- 

 ventrally. The suckers are very large, meetin^f in the middle 

 lino. The rostellum is long, slender, and proboscis-like, 

 measuring about 0*35 mm. in length when fully extended. 

 At the end it expands into a bulb. 'J'ho hooks (fig. 8, B), 

 which were only seen in specimens with the rostellum 

 retracted, are ten in lunnber anil measure ('»'> /x in total length. 

 They are of an unusual shape, having a very long "dorsal" 

 and a greatly reduced " ventral " root. 



Segmentation begins close behind the seolex. In a com- 

 plete specimen there are some three hundred segments, which 

 are broader than long throughout. The cirri, which are 

 usually extruded, are spiny, and, when fully extended, 

 measure about 0*05 mm. in length. The onchospherea 

 measure about 20 fi in diameter. 



Of the species of Aploparaksis hitherto recorded from 

 Anseriform bird.-j, this species is easily distinguished from 

 A. furcigera (Uud.) and ^-1. hiruhii, v. Linst., by the size and 

 shape of its hooks. The hooks of A. fuliijulosa, Solowiow, 

 1911, are undescribed, but the latter form has a smaller 

 seolex and much longer ciiri, among other points of difference. 

 The description of A. elisa, ^kijabin, 1915, I have unfor- 

 tunately been utiable to consult. A. cirrosa (Krabbe), 

 which occurs in Lariformes, has hooks only 22 /i, in length. 



XEMATODA. 



AscaridaB. 



A scaris Ctipstilan'a, Rud. 



Hosts : Cottid fishes. Yukanski, June 1917. 



This immatuie Ascarid, according to views put forward 

 elsewhere by the writer *, is the larval form oi A scan's de 

 ctpiens, Krabbe, which occurs as an adult in seals. The 

 young forms are found in fishes of various geneia and 

 lamiiies, usually coiled up like watch-springs in capsules 

 under the peritoneum. 



1 he piesent exan»j»les came fiom various Cottid fishes, the 

 precise deteiniinaiion of which is unknown. They agree in 

 almost all resjtCets with the description previously given *, 

 • ' Parasitology, ' viii. uo. 3, 1016, p. 3H0. 



e 



