Occasional Papers of the Museum of Zoology 3 



Last ventral plate with sides convex, more strongly so caudad, 

 the caudal margin wide and nearly straight. Anterior legs with 

 tarsi uniarticulate. Anal legs with only the femur (prefemur of 

 Verhoeff) furrowed above, the furrow deepest distally; succeeding 

 joints merely flattened above or the tibia shortly furrowed or 

 notched at distal end. Femur, tibia, and metatarsus flattened 

 along mesal side, or the second and third of these joints somewhat 

 concave along this surface. Femur and tibia each with numerous 

 spinules along dorsomesal surface and along the ventromesal 

 surface, the median region of mesal surface entirely free from 

 them, a tooth toward distal end of ventromesal series as in 

 heathi Chamb.; the ventral surface of femur also with numerous 

 spinules excepting a narrow naked stripe just ectad of the ven- 

 tromesal spinous band; tibia with fewer ventral spinules than 

 femur, the naked space more extensive. Metatarsus with a ven- 

 tral series of four teeth, the first tarsal joint with two. Coxo- 

 pleurae truncate caudally; each with two spinules along caudal 

 border and one farther forward toward ectal border. 



Length, 13 . 5 mm. 



British Guiana: Demerara River, east trail along river bank, 

 collected in very damp clay beneath ground litter of rotten twigs 

 and leaves, F. M. Gaige, August 11, 1914. One specimen, the 

 type, M.C.Z., 2173. 



Apparently most nearly related to the Brazilian C. heathi 

 Chamber lin, which it resembles in the furcate paired sulci of the 

 first segment, etc. It is a larger form in which the last dorsal 

 plate is not so angular caudalh^ and the last ventral plate with 

 caudal margin essentially truncate instead of rounded. The anal 

 legs with tibia and metatarsus not furrowed above, and with 

 spining different; e.g., the spinules along dorsomesal surface of 

 femur and tibia which are absent in heathi, the more numerous 

 ventral spinules of ventral surface with the naked space between 

 them and mesoventral ones, especially on tibia, etc. 



