's RIJKS MUSEUM VAN NATUURLIJKE HISTORIE — LEIDEN. ill 



are flattened in the present form and fringed with long hairs at the 

 margins; the meropodites are armed with a single spine at the posterior 

 border and likewise fringed at both sides. 



Only a single specimen, a female, has been found, „clinging to the 

 floats of a fisherman's net in the K. Ichamutty above Bongong in the 

 Jessore District" (Alcock I.e., p. 409). The author supposes that the shape 

 of the legs enables the animal to swim. 



The following key will serve to distinguish between the species of the 

 present genus. 



1. Carapace very much convex in longitudinal and transverse direction. 



Exognath of external maxillipeds as broad as or slightly broader than 

 ischiognath. Walking legs short, with sparse and very short hairs. 



Surface of carapace deeply furrowed 2. 



Carapace much less convex, especially in transverse direction. Exognath 

 of external maxillipeds distinctly broader than ischiognath. Walking 

 legs longer and somewhat more slender, fringed with long hairs. 

 Surface of carapace finely punctate and regions scarcely or not at 

 all indicated, the cervical groove only being present . . . . 3. 



2. Surface of carapace roughly granulate. Palm of cheliped likewise with 



rounded granules, partly arranged in two longitudinal rows at outer 



surface P. granulosus A. Milne-Edwards 



Surface of carapace punctate. Palm of cheliped smooth, punctate, with 

 two very inconspicuous longitudinal folds at outer surface. 



P. subglobosus n. sp. 



3. Walking legs not flattened; meropodites not hairy, with several teeth 



along posterior border near distal end; dactyli conical, short. 



P. deianira de Man 



Walking leg3 flattened, at least the terminal joints; meropodites hairy 



along both margins, with a single tooth at posterior border near distal 



end ; dactyli flattened, as long as preceding joints. P. fluviatilis Alcock. 



EXPLANATION OF PLATE XL 

 Fig. 1. Pyxidognathus subglobosus n. sp., cT, magn. V/ 2 - Fig. la, external maxil- 



liped, magn. 3. Fig. 16, right chela, outer view, magn. 3. Fig. lc, front 



view of animal, magn. 2. 

 Fig. 2. Pyxidognathus granulosus A. Milne-Edwards, 9? magn. 1 y 2 . Fig. 2 a, front 



view of animal, magn. 2. 

 Fig. 3. Pyxidognathus deianira de Man, <ƒ, magn. 3. Fig. 3a, right chela, outer 



view, magn. 2. Fig. 36, the same, inner view, magn. 2. Fig. 3c, external 



maxilliped, magn. 2. 



