1922] H. A. Baylis and R. Daubney: Parasitic Nematodes. 289 



open to doubt. Ascaris helicina was originally described from Crocodilus acutus ' in 

 America, but has also been recorded from Africa in Crocodilus niloticus more than 

 once, though not hitherto from an Indian crocodile. 



Larvae of Anisakinae. 



Immature Ascarids of various sizes (the longest measuring about 18 mm.) 

 occurred under the peritoneum of the fish Pelamys chiliensis. They have a long 

 ventriculus, and may be the larvae either of an Anisakis or of a Porrocaecum. If 

 the latter, the intestinal caecum has not yet been developed. 



Family HETERAKIDAE, Rauhet and Henry, 1914. 



Subfamily HETERAKINAE, Rauhet and Henry, 1912. 



Genus Heterakis, Duj., 1845. 



Heterakis papulosa (Bloch, 1782). 



Syn. H vesicularis (Frölich, 1791). 



The collection contains examples of this species from the following hosts : 

 Ring-necked pheasant (Phasianus torquatus*). 

 Common hill-partridge (Arboricola torqueola). 



Heterakis isolonche, v. Linst., 1906. 

 Hosts : 



Crimson horned pheasant (Tragopan satyr a). 

 Monâl (Lophophorus impeyanus). 

 Blood pheasant (Ithagenes cruentus). 



An accurate description of this species has been given by Lucet and Henry 

 (1911). The remarkable cuticular "papillae" usually present in the neighbourhood 

 of the vulva of the females are not constant in number or position, and some indivi- 

 duals have none. Moreover, they correspond very closely in diameter with the inter- 

 nal diameter of the preanal sucker of the male. We are therefore inclined to believe 

 that they are actually caused by the action of the sucker of the male in attempting 

 to copulate. It may be that the cuticle of this part of the ventral surface of the 

 female is soft and readily drawn into the sucker. In any case, these raised "hold- 



described by Skrjabin is also present. The spicules are of great relative length and very slender. Gedoelst gives the 

 length of the spicules as 28(V, and does not mention an accessory piece. 280u is slightly less than the length of the 

 accessory piece in our material, and we suggest that this structure has been mistaken for the spicules. We are therefore 

 inclined to believe that our material and Gedoelst's belong to the same specias, but that the form described by Skrjabin 

 is distinct, unless the important structure of the alimentary canal has been overlooked. H The structure of the oesopha- 

 gus and the presence or absence of diverticula of the alimentary canal are characters which we regard as of consider- 

 able systematic value among the Ascaridae ; but, as has been shown above (see Porrocaecum reticulatum) an accessory 

 piece may occur in an isolated species of a genus in which it is normally absent, and we do not feel that it is of equally 

 great systematic importance. 



We wish here to acknowledge our indebtedness to Prof. R. T. Leiper for kindly assisting us to consult Skrjabin's 

 paper. 



l More correctly, C. americanvs. 



