I 



TRILOBIDAE 83 



Cobb, 1894, Proc. Linn. Soc. N.S.W., Sydney, viii, 

 409. 



20. Axonolaimus de Man, 1889. 



Syn. Conolaimus Filipjev, 1918. 



Cuticle unstriated, but with bristles. Head with a crown of 

 four bristles. Lateral organs large, elliptical imperfectly 

 divided by a longitudinal crest. Buccal capsule fusiform, in 

 two parts, the anterior enlarging posteriorly, the posterior 

 diminishing. Oesophagus swollen posteriorly. Caudal end 

 of male without alae or preanal papillae, but with several 

 bristles on the ventral surface of the tail. An accessory piece, 

 with two stout posterior processes, present. Female genital 

 tubes paired, outstretched. Caudal glands present. 



Hab. Marine (in sand). 



Genotype : A. [Anoplostoma] spinosus (Biitschli, 1874). 



Biitschli, 1874, AbJi. Senckenb. Ges., Frankfurt a. M., 273; 

 de Man, 1889, Mem. Soc. Zool. France, ii, 3. 



Conolaimus angustilaimus, according to Filipjev (1918, 

 Trav. Lab. Zool, Stat. Biol. Sebastopol, Ser. II, No. 4, 323), 

 differs from Axonolaimus in the shape and position of its 

 lateral organs, which are more circular in outline and situated 

 very far forward. From Filipjev's figures it appears probable 

 that these differences are largely due to different states of 

 contraction in the mouth region. 



21. Scaptrella Cobb, 1917. 

 The only diagnosis of this genus is contained in the legend 

 to a figure and a " formula." It is said to have the general 

 appearance of Axonolaimus, but to differ from it in having 

 " jointed mandibles," circular lateral organs, a single ovary, 

 and only " faint " accessory pieces. Cuticle coarsely striated. 

 Head with twelve bristles. Testes paired, opposed, out- 

 stretched (?). Female genital tube single, anterior, out- 

 stretched. Spinneret present. 



Hab. Not given. 



Genotype : S. cincta Cobb, 1917. 



Cobb, 1917, Contr. Sci. Nematol, v, 119. 



22. Polylaimium Cobb, 1920. 

 Cuticle very finely striated, apparently without bristles or 

 lateral alae. Head with three or six lips, and without bristles. 

 Lateral organs large, circular. Buccal capsule tubular, 

 elongate, with a narrower anterior and a wider posterior 

 portion. Oesophagus with a very small, elongate or pyriform 

 posterior bulb. Caudal bristles absent. Genital tubes paired, 

 opposed, refiexed. Caudal glands and spimieret present. 

 Apparently hermaphrodite. 



