IRONINAE 141 



4. Ironella Cobb, 1920. 



Cuticle unstriated and without bristles. Slight lateral alae 

 present. Head not distinct, with six small lips and twelve 

 short bristles. Lateral organs apparently consisting of a 

 transverse groove. Pharynx long, tubular. At its anterior 

 end there are three bicuspid teeth projecting into the mouth- 

 opening, and behind these numerous minute denticles. 

 Oesophagus without posterior bulb. Caudal end of male 

 with a single preanal supplementary organ and a large, curved 

 bristle. Testes paired, parallel, outstretched. Female genital 

 tubes opposed, reflexed. Caudal glands and spinneret 

 present. 



Hab. Marine. 



Genotype : /. prismatolaima Cobb, 1920. 



Cobb, 1920, Contr. Sci. Nematol., ix, 277 and key. 



There appears to be nothing to separate this genus from 

 Ironus except the presence of numerous denticles in place of 

 the three posterior denticles of Ironus. 



5. Apodontium Cobb, 1920. 



Cuticle finely striated, with a few bristles towards the 

 extremities. Head not distinct, with four stout bristles. 

 Lateral organs transversely elliptical, open behind. Pharynx 

 narrow, funnel-shaped, with six eversible teeth at its anterior 

 end. Oesophagus cylindroid, without bulb. Caudal end of 

 male without supplementary organs, special bristles or papillae. 

 Spicules slender. Two accessory pieces present, simple and 

 rather stout. Testis single, anterior, outstretched. Caudal 

 glands and spinneret present. Female undescribed. 



Hab. Marine. 



Genotype : A. pacificum Cobb, 1920. 



Cobb, 1920, Contr. Sci. Nematol, ix, 277 and key. 



6. Trissonchulus Cobb, 1920. 



Cuticle unstriated and without bristles. Head distinctly 

 marked off by a constriction, with six swollen lips, each 

 bearing two papillae, one behind the other. Inner surface of 

 each lip beset with numerous minute denticles. Lateral 

 organs pocket-like, with transversely elliptical anterior 

 opening. Pharynx small, containing three forwardly-pointing, 

 apparently eversible teeth. Oesophagus with a slight 

 posterior bulb-like swelling. Caudal end of male with a 

 slight preanal ventral elevation (possibly a supplementary 

 organ), and three pairs of preanal and four pairs of postanal 

 subventral papillae. A slender accessory piece present. 

 Testes paired, opposed, the anterior longer and reflexed, the 



