410 A. E. Verrill — Decapod Crustacea of Bermuda. 



area. Tl}e four antero-lateral spines are usually all similar in size, 

 simple, and mostl}^ acute and curved forward, but the anterior one 

 is often a little shorter than the 2d and rather obtuse; the 2d and 3d 

 are always acute, with the tips bent forward; the 4th is often smaller 

 and more conical and less acute. The surface of the carapace and 

 chelipeds is polished and shining, with no indications of hairs or 

 granulus. 



The chelipeds of the adult males are relatively large and strong, 

 subequal, with the claws gaping. The dactyl is curved, denticulate 

 only distally, with a strongly excavate tip, and it bears a strong tooth 

 about the middle; the thumb has a broader denticulate tooth toward 

 the base. In the young these teeth are absent. 



Figure 42. — Mithrax forceps, hirsutipes, adult male from Bermuda, under 

 side, about nat. size. Phot. A. H. Verrill. 



The carpus and chelae are smooth, with no tubercles except a small 

 denticle on the inside edge of the carpus ; the merus bears two 

 large acute spines on the inner niargin, and about 4 or 5 much 

 smaller, obtuse ones on the outer margin ; the upper surface may 

 have a few minute ones, or in adults a row of two or three obtuse 

 ones. The ambulatory legs are rough with small short spines and 

 long unequal stiff hairs; the dactyls are strong, incurved, with sharp 

 tips; there is a prominent articular plate at the superior distal end 

 of the propodus. 



The basal antennal i)late is wide and thick, tridentate; the outer 

 tooth, Avliich is much the largest, is broad and obtuse, its base 

 occupying about half the width of the plate; the next is not more 

 than half as large and subacute; it is separated from the still smaller 



