Carcinologiml Fauna of hulia. 351 



angles, atid ure more or less sinuous and oblique: tbe eyestalks are 

 very long and are formed as in Ocypoda, but nre mucb slenderer: tbe 

 eyes, thougb chiefly ventral in aspect, arc always terminal. 



Tlie small atitennular flagelbi, wbicli are not bidden under tbe 

 front, fold obliquely. Tbe antenna?, wbicb stand free a(. tbe inner 

 angle of tbe orbits, bavo well developed flngella. 



Epistome, tbougb short, quite distinct. The lateral borders of the 

 buccal cavern are convex outwaids, sometimes so mucb so as to give 

 tbe cavern a subcircular outline. The externa! maxillipeds have a long 

 iscliium and a jsboit and somewhat oblique merus with tbe coarse 

 flagcllum jointed to its anteio-exteinal angle: they close the buccal 

 cavern except for a chink anteriorly. 



The chelipeds differ greatly in tbe sexes. In the female they are 

 equal, are shorter and slenderer than the legs, and have broad-tipped 

 spoon-shaped lingers. In the male one of tbe cbeliiieds resembles 

 tiiose of tbe female, but the other is of relatively gigantic proportions, 

 the Iiand alone being often as big and heavy as all the rest of the 

 animal. 



The legs are stout and end in very sbarj) dactyli, and the meropo- 

 diies of at least tbe 2nd and 3rd pairs are foliaceous : these two jjairs 

 are a little longer than the other two, being about twice the lengtii of 

 the carapace. 



As in Ocypoda, the branchial cavity is capacious, and its lining 

 membi'ane thickened and vascular, with a fleshj' lobe, shaped like a gill- 

 plume, projecting into the space between the tips of tbe last two gill- 

 plumes : also, between tbe basal joints of tbe 2nd and 3rd pairs of legs, 

 there is an orifice, tbickly protected by bairs, leading towards tbe 

 bianchial cavity. 



The abdomen of the male is narrow : in botb sexes of all tbe Indian 

 species it consists of seven separate segments. 



Distribution : all tbe warmer I'cgions of tbe globe, from tbe Atlantic 

 coasts of America eastwards (including the Mediterranean basin) to tbe 

 Pacific coasts of America again. 



The species of Gelasimus are, like the Ocypodes, grogai-ious, and live in warrens 

 in the mud-flats of tropical and subtropical estnarios. Their intelligence, like that 

 of the Ocypodes, is of a high order. 



In one species, at any rate (Gelasimus annulipes), the males, which are greatly 

 in excess of the females, use the big and beautifnlly-colonred cheliped, not only for 

 fighting with each other, but also for "calling" the females. I have described my 

 own observations on these points in the Administration Report of the Mm-ine Survey of 

 India for 1891-92 — reprinted, as an extract, in the Annals and Magazins of Natural 

 History for 1893. 



The fact that the males greatly outnumber, and therefore are more 



693 



