226 IGUANIDA. 
spot anterior to brachium, a broad band connecting the latter with 
the former, and the latter of each side, across posterior gular 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, pl. vii. fig. 8; Baird, U.S. Mex. Bound. Surv., Rept. p. 5, 
pl. xxix. figs. 4-6; Bocourt, Miss. Sc. Mex., Rept. p. 174, pl. xviii. 
fig. 2; Cope, Proc, Am. Philos. Soc, xxii, 1885, p. 395. 
Tropidolepis spinosus, Gray, Griff. A. K. ix. Syn. p. 43; Dum. & 
Bibr. iv. p. 804. 
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. he 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 grey 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 oon oe eesa aes 25 Hind limb........ 72 
Width of head .... 22 AA a cece Araset beet 135 
Body's cawerscns ess 80 
Mexico. 
