304 



Records of the Indian Museum. 



[Vol. VIII, 



lengths of the merus, carpus and chela are respectively as 13, 15 

 and 10. The dactylus is almost exactly equal in length to 

 the palm. 



The second peraeopods may attain a monstrous size in males ; 

 the two limbs may be equal in length or markedly unequal, but 

 as a rule show varying degrees of inequality in large individuals. 

 In very large specimens the greater of the two legs extends 

 beyond the apex of the scale b}' the whole of the chela and 

 carpus. The second peraeopods of eight large specimens yield the 

 following measurements : — 



The whole limb (fig. 21) is closely covered with minute 

 prickles and these become upstanding spinules on the inferior sur- 

 faces of the ischium and merus. The palm is devoid of setae, but 

 both fixed and movable fingers are strongly fluted and, in the 

 hollows between the ridges, are numerous pits from which tufts of 

 coarse hair arise (fig. 22). In living specimens these hairs always 

 retain a quantity of fine mud. The grooving of the fingers is 

 much more marked than in Palaemon dayanus, Henderson, and 

 by this feature alone P. hendersoni is readily distinguished from 

 its allies. The palm is flattened, the depth being scarcely more 

 than three-quarters of the breadth. In large males the fingers are 

 toothed and may gape considerably. The fixed finger usuall}' 

 bears two teeth in its proximal half, while the dactylus also has 

 two, situated distally of those on the opposite edge. The distal 

 tooth of the fixed finger is frequently broad at the apex with two 

 or more tubercles upon it. 



The third peraeopods reach a trifle be3^ond the apex of the 

 antennal scale, the fourth almost to the end of the antennular 

 peduncle and the fifth a little beyond the eye. All three pairs are 

 beset with small prickles, most strongly developed on the posterior 

 surfaces of the ischium and merus, and bear also scattered hairs. 

 On the posterior and postero-internal aspects of the propodus are 



