470 ]\Ir. R. I. Pocock on some new or 



CheJce granular and crested as in T. ecuadorensis ; hand 

 wider than brachium; movable finger with 14 rows of teeth. 

 Pectinal teeth 17-18 



Total lengtli G5 niillini., cara])ace 6, tail 37. 

 Loc. Loja, 2000 ni. (P. 0. Simons). 



Family Chactidae. 

 Genus Megacormus, Karsch. 

 Megacormus seginentatus, sp. n. 



Colour a tolerably uniform reddish brown ; terga with traces 

 of three pale spots, one median and one at each lateral angle ; 

 legs yellow, variegated with deep brown. 



Closely allied to Al. granosus, but differing in iiaving the 

 shaft of the pectines very distinctly segmented, consisting of 

 an apical, a median, and two large basal sclerites. 



Pectinal teeth 4. 



1'otal length 33 millim. 



Loc. Atoyac in Vera Cruz (A. Diighs). 



Genus Plesiochactas, nov. 



Allied to Megacormus^ Karsch, but with the carapace broad 

 and squarely truncate in front ; the stigmata elongate and 

 slit-like, not with the ends strongly curled round as in Mega- 

 cormus, and with distinct '' fulcra " on tlie pectines. 



Type P. Dugesi, sp. n. 



Plesiochactas Dugesi, sp. n. 



Colour nearly black, varied with yellowish red ; terga with 

 a pair of large yellow spots on the posterior border ; coxfe 

 and legs yellowish red^ the cox^ clouded, the legs strongly 

 ringed with black. 



Carapace as long as caudal segment l + 2 + | of 3, a little 

 longer than fifth, coarsely granular; terga coarsely granular, 

 the posterior terga finely and closely granular as well ; 

 sterna and cowce completely smooth, densely punctured, the 

 last sterna only weakly granular, with a median and a pair of 

 lateral abbreviated crests. 



Tail with crests evenly and coarsely granular, the inter- 

 vening spaces sparsely granular, except on the upperside, 

 which has a densely granular median patch ; vesicle granular, 

 fusiform, elongate. 



Chelae with strongly granular crests, intervening spaces 

 sparsely but rather coarsely granular ; brachiura with a few 



