330 Carcinological Fauna of India. 



into the form of an L, ^^^^ liorizoutal limb of which is lodged iu a special 

 trench in the first segment of the sternum. 



Carapace much broader than long, broadest behind. Front narrow, 

 nearly vertically deflexed. Orbits small, circular, widely communicat- 

 ing with the antennular fossae. The antenuules fold transversely. 

 Anteniise small, standing in the orbital hiatus. 



Epistome well-defined. Buccal cavern with the sides slightly 

 convergent anteriorly. The external maxillipeds have coarse palps, 

 which, when folded, fill the rather broad space that exists between the 

 ischiopodites : the merus is subquadrilateral, with the antero-external 

 angle rounded off, and the palp articulates with its antero-internal 

 angle: the exognath is not concealed. 



Chelipeds unequal in the male, shorter but more massive than the 

 legs. 



Only three pairs of legs, the funrtli pair entirely absent. 



Sternum extremely broad. Abdomen of the male very narrow. 

 The efferent ducts of the male sex open on tlie 4th sternal segment 

 inside the fossa into which the abdomen fits. 



82. Lambdophallus sexpes, n. sp. 



Resembles Hexapus sexpus, De Haan, with a specimen of which I have compared 

 it, bat differs in numerous important characters. 



Carapace subquadrilateral with the anterior angles broadly rounded 

 oft', much broader than long, convex fore and aft and anteriorly deflexed, 

 nearly flat from side to side, the gastric and cardiac regions well 

 defined, the surface uniformly finely granular under a lens. 



Front nearly vertically deflexed, its edge square-cut but grooved or 

 notched in the middle line, its breadth about a fifth the greatest breadth 

 of the carapace. 



Orbits freely communicating with the antennular fossa; : eyestalks 

 immovable and very short, eyes small but well pigmented. 



Antennules large, folding transversely ; the inter-antennular septum 

 narrow if complete. 



Epistome lozenge-shaped, well defined: the sides of the buccal 

 cavern converge slightly fiom behind forwards : the ischiopodites of the 

 external maxillipeds are rather narrow and leave between them a widish 

 gap, which, howevei', is filled by the flagella. 



There is a deep crescentic groove across the pterygostomian region, 

 just in front of the bases of the chelipeds, and there are several close-sefc 

 oblique scorings near the antero-lateral angles of the buccal cavern. 



Chelipeds in the male unequal, more massive than the legs, the 

 larger one not li times the length of the carapace : under the lens their 



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