366 BULLETIN 140, UNITED STATES NATIONAL MUSEUM 



Chandler (1925) has recently studied Gnathostome larvae which 

 he found encysted in snakes and in burrows in the liver and peri- 

 toneal walls of cats, in India. He concludes that these must be 

 classed for the present as Gnathostoma pelecani. They differ in 

 certain respects from Chatin's description, however, in that they 

 have 4 cervical sacs of equal length, and the oviduct which can be 

 faintly traced from the vulva leads forward, whereas G. pelecani is 

 described as having 6 cervical sacs of unequal length and the oviduct 

 leading backward. 



Superfamily DIOCTOPHYMOIDEA Railliet, 1916 



Superfamily diagnosis. — Spirurata (p. 162) : Nematodes of median 

 or very large size. Cuticle relatively transparent, at the anterior 

 and posterior extremities transversely striated, with or without 

 spines. Mouth without lips but with 6, 12, or 18 papillae forming 

 1 or 2 circles. Esophagus very long, without bulb; esophageal 

 glands well-developed, all three of about equal size and opening at 

 almost the same level. Male with closed caudal bursa or as the 

 present writer prefers to call it " bursal cup " (an attempt having 

 been made in this paper to confine the term " bursa " to the structure 

 found in the strongyles), bell-shaped, with muscular walls and with- 

 out rays. Female with anus at the very posterior end of body, in 

 middle of obtuse tail. Vulva either in neighborhood of anus or 

 in anterior part of body (1/10 of body length from head end). Va- 

 gina very long. Eggs with thick shell, at the poles of different 

 construction than elsewhere; surface of shell pitted or, rarely, non- 

 pitted but with ridges {Hystrichis acanthocephalicus) . 



Parasitic as adults in digestive tract of birds or kidneys and body 

 cavity of mammals. 



Type- family. — Dioctophymidae Railliet, 1915. 



Various writers refer this superfamily to Railliet, 1910, but the 

 present writer has been unable to verify this earlier date ; moreover, 

 it is unlikely that the superfamily would be created before the 

 family. 



Family DIOCTOPHYMIDAE Railliet, 1915 



Synonym. — Eustrongylidae Leiper, 1908. 



Family diagnosis. — Dioctophymoidea (p. 366) : Characters of the 

 superfamily. 



Type-genus. — Dioctophyme Collet-Meygret, 1802. 



KEY TO GENERA OP DIOCTOPHYMIDAE 



Body without spines ; head with 12 to 18 papillae Eustrongylides, p, 367. 



Body (in at least the anterior region) with spines; head with 6 papillae. 



Hystrichis, p. 375. 



