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



anteriorly, being finely granular : front ending in 

 a triangular projecting beak : ventral surface of 

 ischium of external raaxillipeds of female broad- 

 ly carinate up to a stout terminal tooth : — 



a. Hepatic regions each forming a strong 

 mammary bulge, dorsally, quite independent 

 of the general convexity of the carapace : 

 meropodites of true ambulatory legs perfectly 



smooth L. longifrons, 



j8. Convexities of hepatic regions hardly dis- 

 tinguishable, dorsally, from the general con- 

 vexity of the carapace : meropodites of true 

 ambi^latory legs witli some longitudinal granu- 

 lation : — 

 al. Meropodites of legs with 3 rows of 

 granules : inner edge of hand with several 



rows of granules: size under 25 millim L. neocnledonica. 



a2. Meropodites of legs with a single row 

 of granules : inner edge of hand with a 

 single row of granules : size over 35 millim. L. urania. 

 hh. Thoracic sinus shallow, the convex edge of 

 the pterygostomian region, which defines the 

 sinus anteriorly, smooth and entire : edge of front 

 sharply transverse, and sinuous : ventral surface 

 of ischium of external maxillipeds of female 



non-carinate X. haswelli. 



h. Carapace, excluding the front, as long as broad, 



its posterior margin almost straight Z. marmorea. 



2. Outer edge of hand raised into a sharp carina : pos- 

 terior margin of carapace, in the adult, straight, with 

 its external angles pronounced : — 



i. Front dorsally concave in the middle line an- 

 teriorly : — 



a. Size medium (carapace over 20 millim. long) : 

 thoracic sinus defined ventrally by a row of granules 



of which 3 or 4 are pearl-like L. pallida. 



h. Size small (carapace under 15 millim. long) ; 



thoracic sinus with at most three granules, two of 



which are very large and reniform or fungiform ... L. whitmeei. 



ii. Front convex dorsally in all its extent, produced 



beyond the orbits into a broadly triangular point as in 



L. longifrons L, coralUcola. 



II. Carapace conspicuously longer than broad, sharply 

 hexagonal, devoid of definite pubescence outside of the 

 thoracic sinus, the thickened epimeral edge visible, dorsally, 

 in all its extent when the carapace is held without any 

 inclination straight in front of the observer's eyes : front 

 ending in three sharp horizontal prongs : the thoracic 

 sinus is filled with hair, and is not defined in any part of 



