282 



behind than in front, held down by the incurved postero-lateral angles. Thoracic 

 sternum broad, its last segment atrophied. 



Rostrum acutely triangular. 



Abdomen folded on itself, the telson, which is transversely fissured and 

 very small, is, with the symmetrical caudal swimmerets, folded under the preced- 

 ing somites. The pleura behind the first are fairly well developed. 



Byes well pigmented, the eyestalks short and stout and not dilated. 

 Antennular peduncles weak and flexed ; the lower flagellum very much shorter 

 and slenderer than the upper. 



Antennal peduncles five-jointed, the second joint with a movable acicle : the 

 flagellum of no great length. 



The mandibles, which carry an incurved 3-jointed palp, have the molar 

 process hardly apparent and the edge of the incisor process serrated. 



The exopodites of all the maxillipeds are flagellated. 



There are no epipodites on any of the maxillipeds or thoracic legs. 



The external maxillipeds are pediform with the propodite elongate. 



Chelipeds very much longer and considerably stouter than the legs : the 

 last pair of legs weak and infolded. 



In the male the first 2 abdominal somites carry paired appendages modified 

 for copulation, and rudimentary paired appendages are present on the 3rd and 

 4th somites. In the female paired appendages are present on the 3rd and 4th 

 somites. 



The eggs are large and not numerous. 



The branchial formula is as follows : — 



_ , . . . Arthrobranehise. 



Somites and their Podobranchias ^ „ Plenrobranchiie. 



I s appendages. and epipodites. Antevior . Posterior. 



VII 0=0 



viii 0=0 



IX o 



x o 



XI o 



XII o 



XIII o 



XIV o 



1 0=2 



1 0=2 



1 1=3 



1 1=3 



1 ]=3 



0=1 



Total 6 5 3 =14 (no epipodites). 



Key to the species of Uroptychus of the Indian Benthos and Oligobenthos. 



I. Carapace and chelipeds spi nose ... ... ... ... U. fusimanus. 



II. A pair of spines on the gastric region : chelipeds non-spinose ... TJ. nigricapillis. 



