224 IGUANIDE. 
parietals ; two large auricular scales. Dorsal scales larger than 
ventrals, weakly keeled, shortly mucronate; about forty-three scales 
between the occipital shield and the base of the tail; ten scales cor- 
respond to the shielded part of the head ; ventrals smooth, bicuspid; 
fifty scales round the middle of the body. The adpressed hind limb 
reaches 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 slightly exceeds the distance between the end of the snout 
and the posterior border of the ear. Seventeen (or fifteen) femoral 
pores. Caudal scales a little larger than dorsals. Olive above; a 
black, light-edged collar ; two light bands on the side of the neck, 
the upper from the eye and continuous with the anterior border of 
the collar, the lower commencing at the tip of the snout and passing 
through the ear; gular region and sides of belly blue; chin and 
middle of belly greenish-white. (Male above bluish-black ; dorsal 
scales all with yellow centres.) 
millim. millim. 
Total length ...... 163 Fore limb........ 32 
HCA ie avice wa ov 17 Hind limb........ 45 
Width of head .... 15 Wail Sone dA geet ereie 95 
BOAY: caswastie cere es 51 
Arizona ; North-western Mexico. 
a Q. Ciudad, Mexico. Hr. A. Forrer [C.] 
. Sceloporus ornatus. 
Sceloporus ornatus, Baird, Proc. Ac. Philad. 1858, p. 254; Cope, 
Proce. Am, Philos, Soc, xxii. 1885, p. 396. 
Dorsal scales in about sixty-four transverse series, with but slight 
carination, mucronation and denticulation. Femoral pores twelve. 
A well-marked black cervical collar, complete above and margined 
with yellowish. Colour dark green above, nearly black towards the 
median line; back with small yellowish spots. 
Coahuila, N. Mexico. 
7. Sceloporus dugesii. 
Sceloporus dugesii, Bocourt, Miss. Sc. Mex., Rept. p. 188, pl. xviii. 
fig. 7; Cope, Proc. Am. Philos, Soc. xxii. 1885, p. 396. 
intermedius, A. Dugis, La Naturalesa, iv. 1876, p. 29, pl. i. 
figs. 21-32. 
Head-shields smooth ; supraoculars scarcely enlarged transversely ; 
two canthal scales ; occipital as long as broad, much larger than 
the parietals ; anterior border of ear with a denticulation formed by 
four pointed scales, which are not larger than those preceding, 
Dorsal scales a little larger than ventrals, broader than long, keeled, 
obtuse, not denticulated, converging to the middle line posteriorly ; 
forty-four to forty-eight scales between the occipital shield and the 
