108. 



15. Lip region distinctly set off by a constriction; amohids not visible; 

 two ovaries; spicnla short, no gubemaculum 



Steineriella (Ditlevsen), 1928 



Lip region not distinctly set off; amphids can usually be seen. . . 16 



16. One ovary 17 



Two ovaries 20 



17. Tubiform organ lacking Pseudoncholaimus Kreis, 1932 



Tubiform organ present 18 



18. Tubiform organ pouch-like and without excretory canal; spicula 



straijiht, no gubemaculum O ncholaimus Uujardin, ISUS 



Tubiform organ very complicated 19 



19. Spicula very long, gubemaculum small . Metoncholaimus Filipjev, 1918 

 Spicula not very long, no gubemaculum; male with a large subventral 

 papillae on tail • Oncholainiium Cobb, 1930 



20. Tubiform organ present; spicula long, gi^bernaculum present 



Adoncholaimus Filipjev, 1918 



Tubiform organ lacking; spicula straight, no gubernaculi:im 

 Viscosia de Man, 1890 



21. Stoma with eight teeth Polydontus Schulz, 1932 



22. Hisophagus with a posterior bulb Pelagonemella Kreis, 1932 



Esophagus vfithout a posterior bulb 23 



23. Cuticle thin but distinctly ringed .... Filipjevia Ditlevsen, 1928 

 Cuticle always smooth 2U 



2k. Stoma cylindrical, more than twice as long as broad; amphids smalj,; 



two ovaries; spicula long, bursa present. . Anoplostoma Butschli, 1872 

 Stoma not cylin'lrical; no bursa 2^ 



25. Stoma funnel-shaped 26 



Stoma cup-shaped 27 



26. Stoma small; six lips; ten head setae; one ovary; spicula short but 

 straight, gubemaculum lacking Krampia Ditlevsen, 1921 



27. Stoma distinctly bipartite 28 



Stoma not distinctly bipartite 29 



23. Stoma v-^^ry large with two cuticularized bodies at the base 



Vasculaonema Kreis, 1928 



Stoma very small (1/35 or less of the esopha^^us len2;th) 

 Pseudopelag;ongma Kreis, 1932 



