I9I7.J 



S. Kemp : Notes on Crustacea Decapoda. 



2^1 



The species is described from fifteen specimens, most of which 

 are exceedingly small. They were dredged in the Bidyadhari 

 river near Chingrighatta on the outskirts of Calcutta in October 

 and December 1914. They were found in very foul water which 

 gave specific gravities of i"0045 ^^^ i'oo6o on the two occasions 

 on which the locality was visited. 



The types bear the number 9744/10 Zool. Surv. Ind. 



Genus Hymenicoides^ nov. 



The carapace is nearly circular in outline, sunken, with the 

 usual grooves sharply defined and the lateral margins upturned. 

 The rostrum is altogether absent. The epistome is of moderate 

 length and the buccal cavern is bounded anteriorly by a sharp 

 ridge. The external maxillipedes are slender, gaping widely in the 

 middle line and leaving visible parts of the underlying appendages. 



Fig. 16. — Hynienicoides cavteri, gen. el sp. nov. 

 Anterior part of carapace, seen from below. 



The merus is much longer than the ischium and is more than 

 two and a half times as long as wide ; the dactylus is styliform 

 and of abnormal length, reaching the posterior limit of the buccal 

 cavern when normally flexed (text-fig. 16). The chelipedes in both 

 sexes are stouter than the legs. In the abdomen of the male the 

 terminal segment is trilobate and the sutures of all the segments 

 are distinct. 



This genus is related to Rhynchoplax and Halicarcinus, but 

 differs from both in the absence of the rostrum and in the great 

 length of the dactylus of the external maxillipedes. It resembles 

 Rhynchoplax in the slenderness of the basal segments of the exter- 

 nal maxillipedes and Halicarcinus in having all the segments of the 

 male abdomen distinct. 



Type and only known species, — Hymenicoides carteri , sp, 

 nov. 



