69 



The epistome is wide fore and aft, and is well demarcated from the buccal 

 cavern. 



Though the expiratory channels are very well-defined grooves, there are 

 no distinct crests on the endostome. 



The external maxillipeds do not close the buccal cavern in front, but fall 

 much short of its anterior margin, leaving the expiratory canals permanently 

 open. 



Chelipeds massive, somewhat unequal in the female (male unknown) : a 

 strong spine at the inner angle of the wrist. 



Legs long, stout and compressed, especially as to the merus joints : the 

 dactyli of the first three pairs are styliform : the dactylus and propus of the last 

 pair are broadly foliaceous for swimming. 



This is more closely related to Bathynedes than to any other genus, but in 

 Benthochascon the front is only three lobed, the antero-lateral borders are cut 

 into four teeth only (including the orbital angle), the slender basal antennal 

 joint is shorter, the meropodites of the first three pairs of legs are stouter and 

 more compressed, and the propus and dactylus of the last pair of legs are more 

 foliaceous ; also the carapace is longer, much flatter, and owing to the shortness 

 of the antero-lateral borders, different in shape. 



Benthochascon Hemingl, Alcock and Anderson. Plate III. fig. 2. 



Carapace about seven-eighths as long as broad, its surface very finely gra- 

 nular, its regions faintly marked as inconspicuous swellings separated by shallow 

 and inconspicuous depressions. 



The front forms a thin laminar three-lobed projection. The antero-lateral 

 borders are thin, and are not much more than half the length of the postero- 

 lateral : they are cut into four procurved teeth, of which the foremost is the 

 outer orbital angle and the largest, and the hindmost is spine-like and the longest. 

 The posterior border, between the bases of the last pair of legs, is concave. 



The eyes are large and full, their major diameter being from an eighth to 

 a sixth the breadth of the carapace : the inner suborbital angle forms a thin 

 tooth that is almost as prominent as the outer lobes of the front. 



The chehpeds in the female are about two-thirds as long again as the cara- 

 pace, and their surface is everywhere quite smooth to the naked eye, the hand — 

 of which about half is formed by the fingers — forms rather more than half 

 their entire length : the inner angle of the wrist is a large acute spine, and there 

 is a spinule on the inner upper edge of the palm just behind the finger-joint : 

 the fingers are curved, compressed, hooked at tip, and sharply toothed. 



The first three pairs of legs are nearly twice the length of the carapace, the 

 third pair being slightly the longest : they are smooth and bare. At the far end 

 10 



