296 



Memoirs of the Indian Museum. 



[Voi,. V, 



nal scale (text-fig. 32c) is from 2*4 to 2 - 5 times as long as wide and the straight 

 outer margin terminates in a sharp spine which reaches to, or a trifle beyond, the 

 broad apex of the lamella. 



The outer maxillipedes reach to the end of the second segment of the antennular 

 peduncle and possess an epipod "en crochet." The terminal segment is stouter 

 than the penultimate and is about one and three quarter times its length. 



The first peraeopods of the female are both slender, as in A. dimorphus , and, if 

 extended, would reach, about to the end of the antennal scale; in both sexes they 

 are, however, habitually flexed at the carpo-meral joint. In the female the legs of 

 this pair are equal, or very nearly so, the carpus and ischium are almost equal in 

 length, the merus sometimes just a trifle longer. The chela is about three-quarters 

 the length of the carpus and the fingers are as long as the palm. The segments are 



Fig 32 — Athanas polymorphus, sp. nov. 



a. Anterior part of carapace, rostrum, 



etc. , in lateral view. 



b. do. in dorsal view. 



c. Antennal scale. 



d. Second peraeopod. 



e. Second peraeopod with abnormal 



segmentation. 

 /. Fifth peraeopod. 

 g. Telson. 

 h. Outer uropod. 



devoid of spines and, except for a few hairs on the fingers, are glabrous (text- 

 fig. 31a). 



In males, as has already been explained (p. 291) the legs of the first pair are 

 of three types. In Form I (text-fig. 31&) the limbs are very asymmetrical, one 

 resembling that of the female, while the other is greatly enlarged. The slender limb 

 differs, however, from that of the female in its proportional measurements, the merus 

 being almost one- third longer than the carpus, while the chela is scarcely shorter 

 than the latter segment. The large leg of Form I is very different in structure ; the 

 ischium is quite short and the merus large with its outer lower edge dilated, forming 

 a sort of recess into which the chela fits when the limb is folded. The merus is 

 about five times as long as broad and is only a trifle shorter (as 18 to 19) than the 



