159. 



10. Tail filiform; c = 3.1 - 3.U dolichur^js Loos, 1939 



Tail not filiform; c = 25 or mor^ 11 



11. Tail blunt, straight. . . . conicaudatus (Ditlevsen, 192?) Thorne, 1939 

 Tail arcuate, acute or subacuate 12 



12. Cuticle marked by heavy transverse striae. . . . striatus Thome, 1939 

 Cuticle comparatively smooth 13 



13. Spear length about equal to lip region width ll; 



Spear length about twice lip region width 17 



lU. Lips angular 15 



Lips roxinded 16 



1$. Length over 1.5mm brevidentatus Thome, 1939 



Length less than 0,6 mm minus cuius Loos, 19U5 



16, Rectum shorter than anal body diameter rhaeticus Altherr, 1952 



Rectum longer than anal body diameter arcautus Thome, 1939 



17. Lips set off by constriction 



macrodoroides (Steiner, I9IU) Thorne, 1939 



Lips continuous with neck contour 



faeroensis (Ditlevsen, 1928) Thome, 1939 



Family LSPTONCHIWAE Thome, 1935 

 (Key to the subfamilies from Thorne, 1939) 



Pharynx aimed with an axial spear LEPTONCHNAE Thome, 1935 P. 160 



Pharynx armed with a mural tooth CAIiPYDOHINAE Thorne, 1935 



(Contains a single species C. demonstratus Cobb, 1920) 



Genus of uncertain position: Aulolaimoides Micoletzky. I91I4 



