Boone, Crustacea, Cruises of "Eagle" and " Ara," 1921-28 147 



small but strong ; the merus is compressed and appears to be smaller 

 than the carpus ; there is a decided, transverse, subdistal constriction 

 on the upper, outer and inner faces of the merus ; the carpus is convex 

 on its outer surface, dilated distally and in the small cheliped is about 

 as large and more swollen than the palm of the propodus, while the 

 carpus of the large cheliped is almost as large as that of the propodus. 

 The upper surface of the merus is finely tuberculate and covered with 

 short, stiff bristles; that of the carpus is coarsely tuberculate, rugose 

 and bristle-clad. The propodus of the great chela is about twice as 

 long as the carpus, the fingers comprising approximately one-half of 

 this length ; the palm is quite as high as the carapace and convex ; the 

 upper surface is coarsely and rather thickly tuberculate as is also the 

 upper half of the outer surface, the tubercles vanishing along a diag- 

 onal line extending from the base of the hinged finger to the lower 

 basal margin ; the remaining lower outer surface of the palm is devoid 

 of bristles and is covered with low, flat, scale-like tubercles. On the 

 small chela the entire outer surface of the propodus is covered with 

 bristles and tubercles. The fingers are purplish-black, those of the 

 large chela are widely gaping, except at the tip; the propodal finger 

 is stout and bears one large median tooth ; the hinged finger is longer 

 and curved and bears a small sub-basal tooth ; the fingers of the small 

 cheliped are spoon-shaped at the tip and meet for the greater part of 

 their inner faces, there being only a small gape basally and no teeth. 

 The female chelipeds are ornamented similar to those of the males. 

 The great chela of the male projects conspicuously beyond the cara- 

 pace, its width at the wrist being almost equal to one-half of the width 

 of the carapace. 



The four pairs of ambulatory legs are similar in structure, stout, 

 strong, with the upper, outer and, in a less degree, the lower surfaces 

 densely covered with short, stiff bristles. The first and second pairs 

 are subequal in length, the third pair is a little shorter, reaching to 

 not quite midway the dactyl of the second leg ; the fourth pair of legs 

 are conspicuously shorter, reaching only midway the propodus of 

 the third pair. All four pairs of legs have the meral joint long, wide 

 and flattened with a transverse subdistal constriction and the upper 

 margin finely denticulate ; the carpal joint is narrow proximally, wider 

 distally and about as long and thick as the propodal joint ; the latter 

 narrows slightly distally and is stout and convex outwardly; the 

 dactyli are about three-fourths as long as the propodi and are very 

 strong, cylindrical, curved, terminating in a strong, horny spine. 



