I9I5-] 



Fauna of the Chilka Lake : Crustacea Decapoda. 



285 



from 7 to 9 forwardly directed teeth. On either side the carapace is rather thickly 

 clothed with pkunose setae. A cervical groove {e of Boas' terminology) is distinct, 

 the orbits are semicircular, the infero-orbital angle bluntly rounded and the ptery- 

 gostomian obtusely pointed. 



The eyes are very long and slender and extend beyond the antennular peduncle 

 for a distance equal at least to the length of the last segment of the latter. The 

 stalks are broad at the base, but very narrow in the middle, expanding slightly at 

 the distal end. Each bears a row of setae on the inner margin towards the end of 

 the proximal third of its length. 



The basal segment of the antennular peduncle reaches to half the length of the 



CO. 



Fig. 2^. — 0gyridcs siriaticauda, sp. nov. 



Carapace and anterior appendages, a. Dorsal view. b. Lateral view. 

 The fine setae on the carapace are not shown. 



eyestalks. The lateral process has two ridges, the lower, which corresponds to the 

 outer margin of the process in normal forms and the upper, which is nearly vertical 

 and lies close to the outer edge of the eyestalk. Each of these ridges terminates ante- 

 riorly in a strong spine ; the tips of the spines are on a level and reach to about three 

 fifths the length of the segment. The second segment of the peduncle is rather more 

 than half the length of the first and the third about half the length of the second. 

 The flagella are of the same length, about as long as the peduncle. 



The basicerite of he antenna bears a single external spine; the carpocerite is 

 very long, reaching to the last segment of the antennular peduncle. The autennal 

 scale reaches only to the middle of the second segment of the peduncle ; it is about 



