Carcinological Fauna of India. 235 



and hence forming a very abrupt angle with the anterolateral borders of 

 the carapace : it ends in 3 teeth, of which the two outer are small ami 

 deflexed and only the middle one is large and prominent. As, also, the 

 external orbital angles are inconspicuous, the front, when examined 

 without a lens, seems to end in a single sharp point, as shown in Do 

 Haan's figure. 



3. The thoracic sinus, when denuded of its hair, is a shallow cavity, 

 and the edge of the pterygostomian region that forms its anterior 

 boundary is thickened, smooth, and almost straight. 



4. The chelipeds of the adult male are less than half again as long 

 as the carapace. 



5. The inner surface of the wrist is bounded both above and below 

 by a line of granules. 



6. Colours in spirit : carapace and dorsal surface of chelipedg 

 blue-black; the carapace with two divergent crescents of dark red spots 

 in its anterior half, following the anterior boundary of the epibranchial 

 regions ; tips of arms hands and fingers sometimes nearly white, bases 

 of fingers sometimes yellow. 



17 adults of both sexes (including females with eggs) from the 

 Coromandel coast in 13 to 28 fathoms, and an adult male and female 

 from the Andamans (besides 4 adults from Hongkong) are in the Indian 

 Museum collection. 



66. Leucosia phyllochira, Bell. 



Leucosia phyllocheira, Bell, Trans. Linn. Soc. Vol. XXI. 1855, p. 291, pi. xxxi. fig. 

 5, and Cat. Leucos. Brit. Mus. p. 9. 



This species has a piriform carapace, and is distinguished from all 

 its congeners by the following characters : — 



1. The chelipeds are shorter than the carapace. 



2. The arms have their upper surface much expanded. 



3. The hands are broader than long, are foliaceous, and have both 

 their inner and outer edges strongly carinate. 



A single small specimen from Palk Straits is in the Indian Museum 

 collection. 



Onychomorpha, Stimpson. 



Onychomorpha, Stimpson, Proc. Acad. Nat. Sci., Philadelphia, 1858, p. 162. 



Carapace shaped much like a human nail, depressed, with all its 

 margins, behind the front, forming a continuous laminar brim, increasing 

 in breadth from before backwards and beneath which the true legs are 

 almost entirely concealed in flexion : the expansion of the posterior 



240 



