418 Mr. R. I. Pocock on neio 



The species of the genus Tltyus here recorded from Ecuador 

 may be recognized by the following table : — 



a. Base of pecten bearing a smooth rounded 



prominence at the base of the series of 



teeth (§). 



a^. Conspicuously variegated black and 



yellow. 



ci^. Humerus and brachium of chela not 



strongly mottled Avith black, almost 



entirely pale eciiadorensis, Kraep. 



(From Loja.) 

 b^. Humerus and brachium heavily infus- 



cate zariima;, nov. (Sub- 

 specific form from Zaruma.) 

 6'. Mostly a uniform blackish colour ; not 

 variegated. 

 a^. Tail slender, its intercarinal spaces very 

 ■weakly granular, its crests also weak; 

 sterna weakly granular ; hand narrow, 



but strongly keeled Bosenbe7\(/i, sp. n. 



(Cachavi.) 

 ¥. Tail thick, fourth and fifth segments 

 wider than first ; the intercarinal 

 spaces coarsely and thickly granular ; 

 the upper keels of segments 2 to 5 

 denticulate ; hand broader, weakly 



keeled spinatus, sp. n. (CuenQa.) 



h. Base of pecten without smooth rounded lobe, 

 at most with an angular projection of the 

 shaft (cT). 

 «*. Strongly variegated black and yellow . . ecundorcn^is, Kraep. 



(The forms from Loja and Zaruma dis^tiii- 

 guished as under «'- and b'-.') 

 b^. Not strongly variegated. 



a\ Uniformly black ; sterna weakly gran- 

 ular ; gramiles of caudal keels few and 

 large, median lateral keel complete on 

 second segment; hand narrower, its 

 width much less than half the length 



of movable digit timendus, sp. n. 



(Cachavi.) 

 i\ Legs and chelje paler than trunk and 

 tail ; sterna thickly and rather coarsely 

 granular ; granules of caudal keels 

 weak and numerous ; scarcely a trace 

 of median lateral keel on second seg- 

 ment ; hand very broad, its width 



almost half the movable digit jMu/ilator, .sp. n. 



(Cachavi.) 



