I9 X 5-] Fauna of the Chilka Lake : Crustacea Decapoda. 261 



In the species here described the lateral process of the antennular paduncle is 

 distally rounded, there is no exopod on the first peraeopods, the second peraeopods 

 are comparatively long and reach to the carpus of those of the first pair and there is 

 no appendix interna on the pleopods. In these particulars the species agrees with 

 echinulatus (M. Sars) and with bispinosus (Westwood, = nanus, Kröyer), the latter of 

 which may be taken as the type of Stebbing' s Philocheras. 1 



Pontophilus hendersoni, sp. nov. 

 (Plate XIII, fig. 8.) 



In general appearance this species bears a close resemblance to P. bispinosus 

 (Westwood) . 



The rostrum is broad, parallel-sided, and bluntly rounded apically ; it is deeply 

 channelled longitudinally, the margin forming a raised rim which is contained laterally 

 round the orbits. 



In dorsal view, the carapace including the rostrum) is a little longer than broad. 

 Situated in the mid-dorsal line near the rostral base there is small, sharp, forwardly 

 directed spine, which does not, as in many other species, form the termination 

 of a median carina. On either side behind the middle of the orbit, there is in 

 the anterior third of the carapace a blunt longitudinal ridge, which posteriorly sinks 

 imperceptibly to the general level of the carapace, but anteriorly terminates abruptly 

 in the same latitude as the median spine. A feeble groove defines the upper limit of 

 the branchial chamber and is continued forwards as a shallow depression towards the 

 base of the antennae. This depression is bounded beneath by a blunt ridge which is 

 coterminous anteriorly with the acute antennal spine. There is no hepatic spine. 

 The branchiostegal spine is large and sharp; it is flanked by a short carina and 

 extends far beyond the level of the rostrum (pi. xiii, fig. 8). 



The thoracic sterna are broad posteriorly. The last four are furnished with 

 blunt carinae in the middle, each of which terminates anteriorly in a short spine. In 

 front of them a long and sharp spine projects forwards between the bases of the first 

 legs. 



The eyes are deeply pigmented; their shape, including the stalks, is almost 

 globular. The basal segment of the antennular peduncle does not bear spines either 

 ventrally or at its outer distal end ; its lateral process is subquadrate in outline and 

 is not pointed anteriorly; the second segment is considerably longer than the third ; 

 the greatly swollen outer flagellum of the male is about one and a half times the 

 length of the peduncle (text-fig. 25Ô). The antennal scale is about two and a quarter 

 times as long as broad (text-fig. 25a). The outer margin is almost straight and ter- 

 minates in a large spine which reaches as far forwards as the rather sharply angled 

 apex of the lamella. 



The ultimate segment of the outer maxillipede is broadly rounded apically and 

 scarcely reaches beyond the distal end of the scale. 



1 Stebbing, Marine Invest. S. Africa, I, p. 48 (1902). 



