1897.] 



LIZARDS OF THE GENUS SCELOPORUS. 



511 



sometimes tinged with rusty or orange on the throat and the 

 sides of the belly ; thi-oafc sometimes marbled with grey. 



Hah. This species appears to be distributed over the greater part 

 of Mexico, in the mountains up to 9000 feet. 



21. SCELOPOEUS HETEEOLEPIS. 



Sceloporus heteroleins, Bouleng. Proc. Zool. Soc. 1894, p. 731, 

 pi. xlviii. fig. 4. 



Head-shields smooth ; frontal transversely divided, in contact 

 with the interparietal, or separated from it by a small azj'gous 

 shield ; interparietal as long as broad, or broader than long ; 

 parietals small, sometimes indistinct ; one or two more or less 

 irregular series of transversely enlarged supraoculars, the series 

 surrounded by smaller scales ; two canthal scales ; anterior border 

 of ear with a denticulation formed by three or four pointed scales. 

 Dorsal scales very unequal in size, irregular, some nearly smooth, 

 others strongly keeled ; a pair of vertebral and a dorso-lateral 

 series of large strongly-keeled scales form sorts of crests along 

 the body ; 4-5-75 scales along the median line between the inter- 

 parietal shield and the base of the tail, 10-13 corresponding to 

 the length of the shielded part of the bead. Lateral scales 

 imbricate, small, directed obliquely upwards and backwards. 

 Ventral scales small, smooth, mostly bicuspid. 56-68 scales 

 round the middle of the body. 



The hind limb reaches the shoulder or the ear ; tibia as long as 

 the shielded part of the head ; the distance between the base of 

 the fifth toe and the extremity of the fourth exceeds the distance 

 between the end of the snout and the posterior border of the ear. 

 14 to 19 femoral pores on each side. 



Caudal scales as large as largest dorsals, strongly keeled, spinose. 

 Males with enlarged postanal scales. 



Coloration very much as in S. mierolepidotus. Grreyish or pale 

 brown above, with indistinct darker and fighter blotches and 

 symmetrical blackish markings in the form of transverse or angular 



34* 



