184 Mr. G. A. Boulenger on new 



grey, the throat usually with a dark grey network'; anal region 

 and lower surface of hind limbs bright yellow in the males. 



ruillim. 



Total length 238 



Head 20 



Width of head 14 



Body 03 



Fore limb 30 



Hind limb 51 



Tail 155 



Numerous specimens from Oarao, 8000 feet, Huaras, 

 10,000 feet, and Recuay, 11,000 feet. 



Distinguished readily from the preceding species by the 

 granular patches on the sides of the neck. 



Tropidurus Thomasi. 



Upper head-scales smooth ; a series of four to seven trans- 

 versely enlarged supraoculars ; occipital very large, broader 

 than long, at least as broad as the supraocular region ; nostril 

 above the canlhus rostralis ; ear-opening with a fringe of 

 long pointed scales; temple granulate. A strong curved 

 antehunieral fold, nearly meeting its fellow on the throat; 

 latter with more or less . distinct cross folds ; sides of neck 

 minutely granulate, strongly plicate. Body depressed, with 

 a more or less distinct fold along the side, and a vertebral 

 series of enlarged tectiform scales, forming a low crest on the 

 nape ; dorsal scales very small, juxtaposed, feebly keeled, 

 smaller still, granular, and smooth on the sides; ventrals 

 larger, imbricate, smooth. The hind limb reaches the ear or 

 between it and the antehumeral fold. Tail about once and a 

 half as long as head and body, rounded or feebly compressed, 

 with a low serrated dorsal ridge ; caudal scales much larger 

 than dorsals, keeled and shortly mucronate. Grey above, 

 dotted with blackish and yellowish white, the dots having a 

 tendency to forming transverse series; antehumeral fold 

 black ; throat and breast black in the males. 



millim. 



Total length 165 



Head 15 



Width of head 13 



Body 51 



Fore limb 27 



Hind limb 45 



Tibia 99 



Several specimens from Eton, coast of Peru. 



