1898.] A. Alcock — Carcinological Fauna of India. 79 



gent, straight, with a prominent tubercle at the angle of junction with 

 the anterolateral. 



Front moderately broad, (less than a third the greatest width of 

 carapace) deflexed, 3-lobed, the middle lobe prominent and bilobulate, 

 the edges of all thickened. 



Orbital margins entire, the upper margin thickened and forming* 

 a well-marked blunt tooth at its junction with the antero-lateral margin. 

 Eyes on short thick stalks. 



Antennules folding obliquely, almost transversely : inter-antennu- 

 lary septum broad. 



Basal joint of antennas long, flat, running up into an oblique cleft 

 between the margin of the front and the infra-orbital plate ; the 

 antennary flagellum very small, less than half the diameter of the orbit 

 and lodged in the said cleft. 



Merus of the external maxillipeds with its anterior border very 

 oblique. 



Chelipeds massive, smooth, unequal in both sexes; the fingers 

 bluntly pointed, those of the larger cheliped with a single pair of 

 molariform teeth, those of the smaller cheliped with a blunt cutting- 

 edge. 



Legs smooth, sub-cylindrical. 



Abdomen of male six- jointed — the 3rd and 4th somites fused with 

 obliteration of sutures, the 5th somite also immovably adherent to the 

 4th. Large crabs. 



Key to the Indian species of Carpilius. 



1. Carapace with definitely disposed large red blots ... C. maculatus. 



2. Carapace irregularly marbled with red ... ... C. convexus. 



1. Carpilius maculatus, (Linn.) 



Cancer ruber, Rumph, Amboinsche Rariteitkamer, p. 18, pi. x. fig. 1. 



Cancer saxatile, Seba, Thesaurus, III. 47, pi. xix. fig. 12. 



Cancer maculatus, Linn. Syst. Nat. (xii.) p. 1042 : Fabricius, Ent. Syst. II. 447, 

 and Suppl. p. 338 : Herbst, Krabben, I. ii. 135, pi. vi. fig. 41, and I. ii. 263, pi. xxi. 

 fig. 118, and III. iv. 8, pi. lx. fig. 2 : Desmarest, Consid. Gen. Crust, p. 104. 



Carpilius maculatus, Milne Edwards, Hist. Nat. Crust. I. 382, and in Cuvier 

 Regne Animal, Crust, pi. xi. fig. 2 : De Haan, Faun. Japon., Crust, p., 7 (name only): 

 Dana, U. S. Expl. Exp., Crust, pt. I. p. 160: Stimpson, Proc. Ac. Nat. Sci. Philad. 

 1858, p. 32: Alph. Milne Edwards, in Maillard's Tile Reunion, Annexe F, p. 3, and 

 Nouv. Arohiv. du Mus. 1. 1865, p. 214 and IX. 1873, p. 175 : Heller, Reise Novara, 

 Crust, p. 9 : Hess, Archiv. fur Naturges. XXXI. i. 1865, pp. 133 and 171 : Hoffmann, 

 in Pollen and Van Dam, Faun. Madagasc, Crust, p. 3 ; Richters in Mobias Meeresf. 

 Maurit. p. 145 : F. Muller, Verh. Ges. Basel. VIII. 1886, p. 473 : Miers, Challenger 

 Bracbyura, p. Ill: de Man, Archiv. f. Naturges. LIII. 1887, i. p. 231, and Zool. 



