TRILOBIDAE 87 



Biitschli, 1873, Nova Acta k. Leop.-Car. Akad. Naturf., 

 Dresden, xxxvi, 67; de Man, 1880, Tijdschr. Nederl. dierk. 

 Vereen., Leiden, 31-33 ; 1884, Die frei . . . lebenden Nema- 

 toden d. Niederl. Fauna, 79 ; Micoletzky, 1922, Arch.f. Naturg., 

 Abt. A, Ixxxvii, 195. 



33. Anonchus Cobb, 1913. 



Cuticle finely striated, without bristles or lateral alae. 

 Head with four bristles. Lateral organs spiral. Buccal 

 capsule tubular, unarmed. Oesophagus without posterior 

 bulb. Caudal end of male with twenty tubular supplementary 

 organs. Four to five caudal bristles present. An accessory 

 piece present. Testis and female genital tube single, anterior, 

 reflexed. 



Hab. Fresh water. 



Genotype : A. monohystera Cobb, 1913. 



Cobb, 1913, Journ. Washington Acad. Sci., iii, 444 and key. 



34. Araeolaimus de Man, 1888. 



Syn. Spira de Man, 1877, nee Bastian, 1865. 



Cuticle unstriated, but usually with small submedian bristles. 

 Head without lips, but with a crown of four bristles. Lateral 

 organs spiral. Buccal capsule a rather short, slender tube, 

 narrowing gradually behind. Oesophagus gradually expanded 

 behind. Ocelli sometimes present. Caudal end of male 

 without papillae. Two strongly- curved spicules, and an 

 accessory piece with two posterior processes, present. Female 

 genital tubes paired, opposed. Caudal glands and spinneret 

 present. 



Hab. Marine. 



Genotype : A. [Spira] bioculatus (de Man, 1877). 



de Man, 1877, Tijdschr. Nederl. dierk. Vereen, 's Gravenhage 

 and Rotterdam, 107; 1888, Mem. Soc. Zool. France, i, 14; 

 Filipjev, 1922, Act. Inst. Agronom. Stauropol., i (Zool.), (16), 

 176. 



34a. Subgenus Araeolaimoides de Man, 1893. 



Subgen. of Araeolaimus. The t3rpe of this subgenus differs 

 from that of Araeolaimus in the apparent absence of a buccal 

 capsule and in the oval enlargement of the oesophagus behind 

 the ocelli. 



Genotype : A. microphthalmus de Man, 1893. 



de Man, 1893, Mem. Soc. Zool. France, vi, 86 ; Filipjev, 1922, 

 Act. Inst. Agronom. Stauropol., i (Zool.), (16), 175. 



