216 A. Alcock — Carcinological Fauna of India. [No. 2, 



elegantly to the immobile finger, along which they are usually continued 

 for some distance. The fingers are as long as the hand, and have their 

 opposed edges crenulate throughout their extent. 



The legs have stout subcylinrlrical meropodites (the trigonal origin 

 of which, however, is shown by three longitudinal rows of fine granula- 

 tion), inflated carpopodites, stout dorsal ly-sharp-edged propodites, and 

 broadly lanceolate, or palmulate, dacfcyli. 



The abdomen in both sexes consists of 4 distinct pieces, the third 

 piece in the male bearing a strong tooth in the middle line. 



Colours in spirit: carapace slate-grey with four small ocelli — two 

 on either side of the gastric region : the ocelli have broad red circum- 

 ferences and small white centres : the pearly tubercles of the up- 

 per surface of the arm have the base orange-red and the apex white : 

 the fingers have a yellowish red base, and the legs are indefinitely 

 banded with yellowish red. 



The carapace of an adult of average size, of either sex, is about 

 30 millim. long and 27 millim. broad. 



In India this species has been found only off the Malabar Coast 

 at 45 fathoms. In the Museum collection are an adult male and female, 

 and three half -grown females from the Malabar Coast, (and four adult 

 females from Hongkong.) 



47. Leucosia obtusifrons, De Haan. 



Leucosia obtnsifrons, De Haan, Faun. Japon. Crust, p. 133, pi. xxxiii. fig. 2 : Bell, 

 Trans. Linn. Soc. Vol. XXI. 1855, p. 284, and Cat. Leucos. Brit. Mus. p. 6: 

 A. Ortmann, Zool. Jahrbucher, Syst. etc. VI. 1892, p. 585. 



Differs from L. unidentata, De Haan, only in the following charac- 

 ters, adults of both sexes being compared : — 



1. The puckered mouth of the pterygostomian invagination — or 

 thoracic sinus — is still visible in all its extent as a long loop of granules 

 lying between the base of the chelipeds and the eave of the carapace ; 

 but the granules of the dorsal limb of the loop are so small as to be 

 only visible with a lens ; those of the front convexity of the loop have — 

 by a further infolding of the pterygostomian region — become partly 

 welded together and cut off to form an almost isolated ring ; while only 

 those that form the ventral limb of the loop remain as large separate 

 granules. 



2. The two rows of tubercles on the upper surface of the arm are 

 shorter, ending within the proximal half of the arm. 



3. The chelipeds, in the adult male, are less than half again as 

 long as the carapace. 



4. The dactyli of the legs are narrowly lanceolate, not palmulate. 



