50 ASCAROIDEA 



de Man, 1889, Mem. Soc. Zool. France, ii, 8; Filipjev, 1918, 

 Trav. Lab. Zool, Stat. Biol. Sebastopol, Ser. II, No. 4, 186; 

 1922, Act. Inst. Agronom. Stauropol, I, (Zool.), 16, 110. 



5. Dermatolaimus Steiner, 1916. 



Cuticle striated. Body without bristles. Four submedian 

 cephalic bristles present. Head distinct, abruptly conical. 

 Lateral organs circular, incomplete behind, with posterior 

 prolongations. Apparently no lips. Buccal capsule very 

 narrow and elongated. Oesophagus slender, expanding 

 gradually into a posterior bulb. Male unknown. Female 

 genital tubes paired, symmetrical, reflexed. 



Hab. Marine, arctic. 



Genotype : D. ditlevseni Steiner, 1916. 



Steiner, 1916, Zool. Jahrb., Syst., xxxix, 603. 



6. Gymnolaimus Cobb, 1913. 



Cuticle unstriated. Lips inconspicuous, three in number ( ?). 

 Cephalic bristles absent. Lateral organs absent. Buccal 

 capsule very long, slender. Oesophagus cylindrical, joined by 

 a narrow neck to a pyriform bulb. Tail in both sexes long 

 and tapering. Vulva at about the middle of the body. Female 

 genital tube single, outstretched. Caudal glands and spin- 

 neret absent. 



Hab. Soil. 



Genotjrpe : G. [Aulolaimus] exilis (Cobb, 1893). 



Cobb, 1893, Macleay Mem. Vol., Linn. Soc. N.S.W., Sydney, 

 289; 1913, Journ. Washington Acad. Sci., 434. 



7. Leptolaimus de Man, 1876. 



Cuticle of body striated, with lateral alae and occasional 

 bristles. Head distinct, without lips or bristles. Lateral 

 organs circular. Buccal capsule an elongate, thin-walled tube. 

 Oesophagus cylindrical, swollen into a bulb posteriorly. Tail 

 of male slender, with several lateral " bristle-papillae " and 

 with a knob-like termination on which the caudal gland opens. 

 A median row of preanal papillae present, extending from just 

 in front of the cloaca to the posterior oesophageal region, the 

 four most anterior papillae being tvibular and chitinized. 

 Spicules slender. A single accessory piece present. 



Hab. Soil, or brackish water. 

 Genotype : L. papilliger de Man, 1876. 



de Man, 1876, Tijdschr. Nederl. dierk. Vereen., 's Gravenhage 

 and Rotterdam, 168 ; 1884, Die frei . . . lebenden Nematoden 

 der Niederl. Fauna, 81. 



