24 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 89 



dition not known to occur in any other member of the order. Lateral 

 or ventral striae not extending beyond the tips of the legs. 



Last segment with the entire margin thickened, including the apex, 

 which equals or just exceeds the valves. 



Anal valves meeting in a deep groove, the margins not compressed. 



Gonopods somewhat intermediate between those of Rhinocricus 

 and Microspiroholiis, but other characters point to closer relationship 

 with the latter genus. 



APOROBOLUS CRUSOI, n. sp. 



One male and six females were collected February 20, 1932, at 

 Man-of-War Bay, Tobago, the site of Robinson Crusoe's shipwreck. 



Description. — Length of the largest specimen, a female, 20 mm, 

 width 2 mm. Number of segments 35 to 38. 



Fig. 12. — Aporobolus criisoi. a, antenna; b, gonopod, anterior view; c, gonopod, 

 posterior view. 



Living color white with a black stripe along the middle of the dorsum 

 and another along each side. 



Head with a short, deep furrow on the vertex ; clypeus with four 

 fovea on each side ; ocelli rather large, 15 to 19 in number and arranged 

 in three series ; antennae deepset on the sides of the head, the cardo 

 of the mandibles broadly and deeply excavated for their reception, 

 basal joint long and thick, equaling or slightly exceeding joint 6 in 

 both dimensions (fig. 12, a) ; sense cones four. 



First segment with the sides narrowed, slightly emarginate in front 

 and back just above the lateral margin. Anterior margin with a strong 



