72 LACERTILIA. 
18. Sceloporus ornatus. 
Sceloporus ornatus, Baird, Proc. Ac. N. Se. Phil. x. p. 254; Cope, Proc. Am. Phil. Soc. 1885, p. 396. 
Hab. Mexico, Patos in Coahuila (Couch, U. S. Nat. Mus.), Nuevo Leon (W. Taylor). 
From forty-eight to fifty scales in a series along the middle of the back. Scales 
with feeble keels. The large supraoculars divided. Hind limb as long as the dis- 
tance of the vent from the collar; fourth toe rather shorter than the head. Sixteen 
or seventeen femoral pores. Greenish; blackish along the middle of the back, with 
light small spots; a rather broad and complete black collar edged with light green 
across the neck. Male with the throat and sides of the abdomen blue. 
An (adult ?) male specimen is 26 lines long without tail. 
19. Sceloporus rubriventris, sp. n. (Tab. XXXII. fig. C.) 
Hab. Mexico, Omilteme in Guerrero (H. H. Smith). 
Forty-eight or fifty scales in a series along the middle of the back. Dorsal scales 
with a small terminal spine, their keels forming lines which converge towards the 
median line. The larger supraoculars in a double row; two canthal scutes. Hind 
limb rather shorter than the distance between vent and collar; fourth toe longer than 
the head. From sixteen to eighteen femoral pores. Greenish-bronze coloured, marbled 
above ; ablack band from the tympanum above the collar-fold and shoulder, a black line 
from the eye to the tympanum. Both sexes with the throat and a broad band along each 
side of the abdomen orange-coloured, the middle of the abdomen being greenish. 
An adult male is 24 inches long without tail. 
This very distinct form is allied to S. microlepidotus, but has larger scales and 
a different coloration of the abdomen. 
20. Sceloporus microlepidotus. 
Sceloporus microlepidotus, Wiegm. Herpet. Mex. p. 51; Bocourt, Miss. Sc. Mex., Rept. p. 194, 
t. 18 bis. figg. 18, 18 a-d; Cope, Proc. Am. Phil. Soc. 1885, pp. 170, 379, 384, 397; Boul. 
Cat. Liz. li. p. 232. 
Sceloporus dispar, Baird. & Gir. Proc. Ac. N. Se. Phil. vi. p. 127. 
Hab. Mexico, Ventanas and Ciudad in Durango (Forrer), Colima (U. S. Nat. Mus.), 
Guanajuato, Puebla (Dugés, Mus. Brit.), Oaxaca (Boucard), Orizaba (Mus. Brit.), 
Jalapa (Hoge), Tezuitlan (Ferrari-Perez), Zacualtipan (Cope), Popocatepetl in pine 
forests 9000 feet (F. D. G.), Mirador, Vera Cruz (Sartorius, U.S. Nat. Mus.). 
From sixty-two to sixty-eight scales in a series along the middle of the back; dorsal 
scales not mucronate, in series converging towards the median line. Supraoculars 
small, in several series. Hind limb rather shorter than the distance of the vent from 
the collar; fourth toe rather longer than the head. From fourteen to eighteen 
