Boone, Crustacea, Cruises of "Ara" and "Alva" 259 



subequal in length to the fixed finger, slightly slenderer proxi- 

 mally and with the outer margin curved, the apices meeting ; an 

 elliptical hiatus exists between the fingers, each of which bears 

 on the cutting edge six teeth, the proximal of which is a low 

 molar, followed by four longer, closely spaced, cylindrical, bluntly 

 rounded distally teeth, and more widely spaced, a fifth similar 

 tooth ; the apices of the fingers are curved, acuminate teeth, that 

 of the lower finger overlapping that of the upper one. Numer- 

 ous tufts of stiff bristles occur between the teeth. The entire sur- 

 face of the great cheliped is continuously beset with coarse, 

 rough, brown spines, those on the ischium and proximal merus 

 being weak, these murications consistently increasing in size 

 distad on each joint, also in size distad on the successive articles, 

 the smaller spines of the propodus being as large as the larger 

 ones of the more proximal joints. On the distad half of the palm, 

 also on the fingers, these spines become quite large. Some on the 

 ventral-distal palm have their inferior surface grooved, file-like. 



The smaller male cheliped, when extended, reaches only to the 

 proximal end of the palm of the opposed great cheliped, the con- 

 tour of the respective joints being similar; the propodus has the 

 fingers about one-sixth to one-fifth longer than the palm, which 

 is short, not quite 1.5 times the length of the carpus and only 

 moderately inflated ; the fingers are long, slender, subequal, with 

 broad, rounded spoon-tips, the two cutting edges are each set 

 with shallow, insignificant denticles, but are furnished along 

 either side of their cutting edges with a double longitudinal series 

 of tufts of coarse bristles, these being more numerous, sieve-like, 

 on the upper side. Like the large, opposed cheliped, the surface 

 of the smaller great cheliped is entirely covered with spinose 

 murications, similarly arranged, those of the smaller cheliped 

 being correspondingly smaller. 



The female second pair of chelipeds are occasionally almost 

 equal, more frequently one is about ten per centum longer than 

 the other, distally weaker than the smaller great cheliped of 

 the male, but of similar structure. The female has the palm no 

 longer than the related carpus, the fingers being about 1.3 times 

 as long as the palm, slender, meeting throughout their entire 

 length, augmented with numerous tufts of bristles, apices spoon- 

 shaped. 



