226 IGUANID^. 



spot anterior to brachium, a broad band connecting the latter with 

 the former, and the hitter of each side, across posterior guhir region, 

 black, which shades into blue on the sides and throat; chin light 

 green ; brachium black in front. 



From snout to vent 97 millim. 



Lower California. 



10. Sceloporus spinosus. 



Tropidolepis spinosus, Gray, Cat. p. 209. 

 Sceloporus spinosus, Wiegm. Isis, 1828, p. 370, and Herp. Mex. 



p. 50, pi. vii. fig. 3 ; Baird, U.S. Mex. Bound. Surv., Bept. p. 5, 



pi. xxix. figs. 4-6 ; Bocoitrt, Miss. Sc. Mex., Bept. p. 174, pi. xviii. 



fig. 2 ; Cope, Vroc. Am. Philos. Soc. xxii. 1885, p. 395. 

 Tropidolepis spinosus, Gray, Griff. A. K. ix. Syii. p. 43; Dum. c^ 



Bibr. iv. p. 304. 



Head-shields smooth ; a series of three or four large transversely 

 dilated supraoculars ; two canthal scales ; occipital as long as broad, 

 broader than the parietals, which are rather large ; anterior border 

 of ear with a strong denticulation formed of four or five pointed 

 scales, the two upper of which are usually larger than those pre- 

 ceding. Dorsal scales much larger than ventrals, as broad as long, 

 strongly keeled and mucronate, distinctly denticulated, forming 

 parallel longitudinal series ; twenty-eight to thirty scales between 

 the occipital shield and the base of the tail ; five or six scales (seven 

 in the young, owing to the proportionally larger head) correspond 

 to the length of the shielded part of the head ; lateral scales keeled, 

 directed obliquely upwards and backwards, graduating into the 

 dorsals and ventrals ; latter smooth, bicuspid ; thirty-six to thirty- 

 eight scales round the middle of the body. The adpressed hind 

 limb reaches the shoulder or the ear; tibia, in the adult, longer 

 than 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. 

 Seven to ten femoral pores. Caudal scales as large as or a little 

 smaller than dorsals. Male with enlarged postanal scales. Pale 

 olive or yellowish-brown above, with dark brown transverse spots, 

 and a more or less distinct, broad, lighter dorso lateral band ; head 

 frequently with fine brown transverse lines across its upper surface 

 and others radiating from the eye : lower surfaces whitish, throat 

 longitudinally streaked with gre}' or blackish ; male with a black 

 antehumeral spot usually connected with its fellow on the throat ; 

 the whole or part of the gular region, and the sides of the abdomen, 

 blue ; pectoral region and median ventral zone whitish. 



millim. millim. 



Total length 240 Fore limb 48 



Head 25 Hind limb 72 



Width of head . . . . 22 Tail 135 



Body 80 



Mexico. 



