554 DISCOVERY REPORTS 



diameter, its posterior portion being club-shaped. Its length is 0-9-1 mm. There is a 

 large intestinal caecum, which runs forward ventrally to the oesophagus almost as far as 

 the nerve-ring. The excretory pore is situated 

 at 0-35-0-37 mm. from the anterior extremity 

 of the worm. 



The caudal end of the male is curved ventrally. 

 The tail is conical and sharply pointed, and 

 measures 0-21 mm. in length. The usual preanal 

 sucker-like organ is present. There are ten pairs 

 of caudal papillae, of which five are preanal. Their 

 arrangement is indicated in Fig. 1 1 . The spicules 

 are about 0-85 mm. long, and the accessory piece 

 about o-i mm. 



The tail of the female is straight and conical, 

 measures 0-2-0-22 mm. in length and is usually 

 tilted dorsally at an obtuse angle. The vulva, 

 which has very prominent lips, is situated at 

 2*3 mm. from the posterior end in a specimen 

 6-3 mm. long. The vagina and the common trunk 

 of the uterus run anteriorly from it. At a point 

 slightly in front of the middle of the body the 

 common trunk divides into two branches. One 

 of these runs straight forward, and the coils of its 

 ovary extend as far as the junction of the oeso- 

 phagus and intestine. The other branch almost 

 immediately turns posteriorly, and the coils of 

 its ovary extend nearly as far as the anus. The eggs measure about 0-09 mm. x 0-05 mm. 



This species would fall into the genus Dichelyne Jagerskiold, 1902, as recently 

 re-defined by Gendre (1927, p. 261). This genus was suppressed by the writer (1923 h, 

 p. 233) as a synonym of Cucullanus. The only real character which can be adduced to 

 separate it from the latter being the presence of an intestinal caecum, the revival of the 

 genus Dichelyne does not appear necessary unless a further study of the contained species 

 should reveal other important distinguishing characters. 



Fig. II. Cucullanus fraseri. Posterior end 

 of male, lateral view, a.p., accessory 

 piece; sp., left spicule; su., sucker- 

 like organ. 



Cucullanus fraseri, var. nototheniae, nov. 



Examples of a form scarcely specifically distinct from that just described, but larger, 

 occurred in the intestine of Notothenia gibberifrons off South Georgia (Station 123), 

 December 15, 1926. The male measures nearly 7 mm., the females up to 9-6 mm., in 

 length. The cervical papillae, instead of being in front of the nerve-ring, are some 

 distance behind it (o-6 mm. from the anterior end in the male, 0-65-0-7 mm. in the 

 female). 



