TRILOBIDAE 85 



26. Krampia Ditlevsen, 1921. 



Cuticle apparently unstriated, with a few rather fine bristles 

 anteriorly. Head somewhat distinct, truncate, with four ( ? ) 

 rounded, somewhat swollen lips, and with a crown of stout 

 bristles. Lateral organs unknown. Buccal capsule funnel- 

 shaped. Oesophagus gradually swollen behind, and with 

 chitinoid thickenings externally at the level of the buccal 

 capsule. Male without accessory piece, supplementary organs 

 or caudal papillae. Female genital tube single, anterior. 



Hab. Marine. 



Genotype : K. acropora Ditlevsen, 1921. 



Ditlevsen, 1921, Vid. Medd. Naturh. Foren., Copenhagen, 

 Ixxiv, 57. 

 I 27. Leptogastrella Cobb, 1920. 



Cuticle finely striated, with bristles in cervical and caudal 

 regions. Lateral alae absent. Head with three or six lips 

 and a crown of eighteen to twenty bristles. Lateral organs 

 inconspicuous. Buccal cavity wide and funnel-shaped. 

 Oesophagus without posterior bulb. Caudal end of male 

 without supplementary organs or papillae. The spicules 

 slide in tubular accessory pieces. Testis and female genital 

 tube single, anterior, outstretched. Caudal glands and 

 spinneret present. 



Hab. Marine (in mud). 



Genotjrpe : L. 2idlucida Cobb, 1920. 



Cobb, 1920, Contr. Sci. NematoL, ix, 249 and key. 



28. Margonema Cobb, 1920. 



Cuticle unstriated, without bristles or lateral alae. Head 



' not distinct, with three double lips but without bristles. 



I Lateral organs spiral. Buccal cavity large, continuous ■^fith 



lining of oesophagus. Oesophagus without bulb. Male 



with thirty to forty supplementary organs close together, and 



i a few scattered subventral caudal bristles. Accessory pieces 



I with posterior processes. Testis single, anterior, outstretched. 

 Female genital tubes paired, opposed, outstretched. Caudal 

 glands and spinneret present. 



Hab. Marine. 



II Genotype : M. ringens Cobb, 1920. 



Cobb, 1920, Contr. Sci. NematoL, ix, 248 and key. 



29. Xenolaimus Cobb, 1920. 



Cuticle coarsely striated, without bristles but with twelve 

 longitudinal alae. Head protrusible, with a cuticular collar. 

 Six thick, somewhat digitate lips and a crown of cephalic 



