370 Carcinploglcal Fauna of India. 



Chelipeds about twice as long as the carapace : tympanum on the 

 innei* surface of the arm large, that on the outer surface of the arm 

 small : fingers about as long as the palm, without any enlarged 

 teeth. 



First 3 pairs of legs about the same length as the chelipeds, the 

 4th pair shorter : the merus of all much dilated and with large well- 

 defined tympana, all of which, except only tlie one on the dorsal surface 

 of the last pair, are longitudinally subdivided by a fine ridge : the 

 dactylus in the first 3 pairs is about the same length as the propodite, 

 but in the last pair is considerably longer. 



In the male abdomen the first 2 segments are horizontal-linear, the 

 3rd and 4fch, though distinct, form a *' butterfly " plate, the 5th is long 

 and narrow and longitudinally grooved and gradually expands to meet 

 the 6th, which is long and broad, while the 7th is transversely 

 oval. 



In the female the abdomen is of the usual shape, but in its broadest 

 part is little more than half the breadth of the sternum. 



In the Indian Museum are 11 specimens, from Diamond Island off 

 C. Negrais in Burma. The carapace of the largest male is 45 millim. 

 long and 7 millim. broad. 



65. Scopimera crabricauda, n. sp. 



Carapace subpentagonal, the regions indistinctly indicated, the 

 surface of the mid-dorsal region is symmetrically puckered or vesicu- 

 lous ; the sidewalls and pterygostomian regions granular. 



Orbits modei'ately bi^oad and deep, the upper border oblique, the 

 lower border prominent and finely denticulate. 



External maxillipeds smooth: chelipeds and legs "frosted" under 

 the lens. 



In the male the chelipeds are more than 2| times the length of the 

 carapace and are longer and much stouter than the legs : there is a large 

 tympanum on the inner surface of the arm, and a very small one on the 

 outer surface : the dactylus is a little shorter than the palm and has 

 one large tooth. In the female the chelipeds are shorter and not much 

 stouter than the legs : the fingers are shorter than the palm, and the 

 dactylus has no large tooth. 



The meropodites of the legs are much dilated : all have tympana 

 but these are. not subdivided by any i-idge : in the first 3 paii^s of legs 

 the dactyli are a little longer, in the fourth pair considerably longer, 

 than the propodites. 



In the male abdomen the first 2 segments are linear-horizontal and 

 concealed, the 3rd and 4th form a triangular plate deeply grooved dowa. 



712 



