Carcinolugical Fauna of India. 217 



5. On either side of the gastric region are two white spots, instead 

 of two red and white ocelli. 



6. The body is somewhat smaller, the carapace in the average 

 adult male measuring 25 by 23 millim., and in the average adult female 

 26 by 24 millim. 



In the Museum Collection are 2 adult males, 4 egg-laden females, 

 2 young males, and a young female, from the Coromandel Coast. 



The structural and colour differences hold good irrespective of age 

 or sex, and 1 therefore think that De Haau's separation of this species 

 from the preceding is justified. 



48. Leucosia longifrons, De Haan. 



? Cancellus anatum secundus, Rumph, Amboin. Rariteitkamer, I. 27, pi. x. fig. B. 



? Araneus marinus, Seba, Thesaurus, III. 46, pi. xix. figs. 4, 5. 



Leucosia longifrons, De Haan, Faun. Japon. Crust, p. 132, pi. xxxiii, fig. 4 : 

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

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



? Leucosia urania,, Guerin, Icon. R. A. Crust., pi. vi. fig. 4 (nee Herbst). 



Leucosia polita, Hess, Archiv fur Naturges. XXXI. i. 1865, pp. 155 and 172, pi. 

 vi. fig. 14; (and ? Haswell, Cat. Austral Crust, p. 120); fide de Man, Zool. Jahrbiich. 

 Syst. etc., II. 1892, p. 585. 



Leucosia ornata, Miers, Trans. Linn. Soc, Zool., (2) 1. 1875-79, p. 236, pi. xxxviii. 

 figs. 7-9. 



Leucosia urania, de Man, Journ. Linn. Soc, Zool., Vol. XXII. 1888, p. 197 (nee 

 Herbst). 



Carapace bluntly rhomboidal, about nine-tenths as long as broad : 

 its surface perfectly smooth and devoid of hair : its antero-lateral bord- 

 ers finely beaded, and strongly sinuous, owing to the prominence of the 

 edge of the well-defined hepatic region : its true postero-lateral border 

 beaded only as far as the level of the first pair of legs (2nd pereiopods) : 

 its thickened milled epimeral border is visible, dorsally, only in its post- 

 erior third when the carapace is held, without any inclination, straight 

 in front of the observer's eyes: its posterior margin short, gently 

 curved, and finely beaded, with the deflexed surface below it quite 

 smooth. 



The thoracic sinus is no longer recognizable as the puckered mouth 

 of a simple pterygostomian invagination: it is now a roughly Y-shaped 

 cavity, the tail of the Y being defined by a line of 6 or 7 large pearly 

 granules continuous with the milled epimeral edge of the carapace, the 

 concavity of the fork of the Y being defined by the convex crenulated 

 edge of the pterygostomian region, and the outer limb of the Y being 

 a good deal longer than the inner. 



The hepatic regions are strongly convex dorsally, their convexities 

 being quite independent of the general convexity of the carapace. 



222 



