Opisthophthalmus in the British Museum. 217 



gular piece, the two grooves mentioned under 

 a being obsolete. 



'. Ocular tubercle just behind the middle of 

 the carapace ; penultimate segment of the 

 first three pairs of legs not spined exter- 

 nally ; vesicle granular WaMbergi (Thor.). 



'. Ocular tubercle far behind the middle of the 

 carapace ; penultimate segment of legs of 

 first three pairs spiny externally. 

 a 5 . Vesicle distinctly granular below (inter- 

 ocular area of carapace smooth, last ab- 

 dominal sternite weakly granular in $ ) . . nitidiceps, sp. u. 

 b b . Vesicle smooth below, at most granular 

 quite at the base. 

 a 6 . ( 2 •) Tail short, 3 or 3s times as long 

 as the carapace, which is about as long 

 as the first, second, and third caudal 

 segments ; hand of chela thicker, 

 heavier, and less hairy ; genital oper- 

 culum not divided. 

 a 1 . Last abdominal sternite roughened, 

 at least mesially, with irregular 

 granulation ; inferior surface of the 

 first caudal segment with roughened 

 keels. 

 a s . All the terga distinctly granular ; 

 interocular area finely so ; last 

 abdominal sternite granular 

 throughout ; colour darker, max- 

 illos of first and second legs deep 



black pufjnax, Thor., $ . 



b\ Terga and interocular area entirely 

 smooth, or, at most, finely granu- 

 lar ; last sternite mesially rough- 

 ened; colour paler, maxillary 



processes not blackened ylabrifrons, Pet., $ . 



b 1 . Last abdominal sternite not granu- 

 lar, at most punctured ; inferior 

 keels of first caudal segment smooth 

 (each marked with two punctures). 

 u n . Interocular area rugose inferior 

 median keels of first caudal seg- 

 ment strong ; colour entirely 



blackish calvus, L. Koch, 2 ■ 



b'\ Interocular area polished, smooth ; 

 inferior median keels of first 

 caudal segment weak ; colour 



reddish brown latimanus, C. Koch, $? . 



V s . ( S ■) Tail from 4 to 4| times the length 

 of the carapace ; hand much thinner 

 and more hairy. 

 a 10 . Sterna of abdomen smooth, the last, 

 at most, granular laterally. 

 n 11 . Tail narrow, compressed; den- 

 ticles of upper keels on segments 



