116 ASCAROIDEA 



Hab. Marine. 



Genotype : P. cocksi Bastian 18G5, according to Stiles & 

 Hassall (1905). 



Bastian, 1865, Trans. Linn. Soc. London, xxv, 142. 



13. Anaxonchium Cobb, 1920. 



Cuticle rather coarsely striated, without bristles. Lateral 

 alae present. Head not distinct, with a crown of ten short, 

 stout, two-jointed bristles. Lips apparently six, bilobed, 

 each bearing externally a short bristle and two longer appen- 

 dages with expanded ends (according to the figure, with 

 which the description does not altogether agree). Lateral 

 organs " peculiar, large, faint " (according to figure, incipient 

 spirals). Pharynx narrow, largely occupied by a well-developed 

 dorsal tooth. Opj)osite to this several smaller teeth, of which 

 two subventral ones are probably the largest. Apparently 

 small denticles also occur dorsally to and in front of the 

 large dorsal tooth. Oesophagus without posterior bulb. 

 Male with a series of fifteen to twenty preanal supplementary 

 organs and a few small caudal bristles*. Spicules rather 

 broad. Two " somewhat shoe-shaped " accessory pieces 

 present, with a median piece between and behind them. 

 Testis single, anterior, reflexed. Female unknown. 



Hab. Marine (in sand). 



Genotype : A. litorium Cobb, 1920. 



Cobb, 1920, Contr. Sci. Nematol., ix, 319 and key. 



14. Thobnchus Cobb, 1920. 



Cuticle finely striated. Head not distinct, with six lips, 

 six papillae and ten bristles. Lateral organs apparently 

 transversely elliptical. Pharynx rather wide, goblet-shaped, 

 containing a rather small dorsal tooth and two subventral 

 teeth at its base. In front of these teeth the walls of the 

 pharynx bear numerous small denticles. Oesophagus gradu- 

 ally swollen behind, without bulb. Caudal end of male with 

 a single preanal supplementary organ in the form of a trans- 

 verse ridge, a pair of subventral preanal papillae, and a few 

 short preanal and postanal bristles. Spicules rather stout. ' 

 Accessory piece ( ? single) with expanded lower end in which I 

 spicules slide, and without posterior process. Testes paired,! 

 opposed, outstretched. Female genital tubes paired, opposed,! 

 reflexed. Caudal glands (preanal) and spinneret present. 



Hab. Marine. 



Genotype : T. ferox Cobb, 1920. 



Cobb, 1920, Co7itr. Sci. Nematol, ix, 310 and key. 



