420 REPORT OF NATIONAL MUSEUM, 1898. 



characters: Interorbital space narrower; occipital spines implanted 

 obliquely; occipital tubercles smaller, and consequently more numer- 

 ous; trihedral scales of all parts of the body more bristling; and the 

 gular scales feebly keeled and not eutirely smooth. (Bocourt.) 



The erect direction of the occipital spines of this species distiuguishes 

 it from the others of the orhiculare group. 



No specimens of the Phrynosoma houcardii are in the U. S. National 

 Museum. M. Bocourt's specimens came from the "Plateau of Mexico," 

 without further specification of locality. 



PHRYNOSOMA SOLARE Gray. 



Phrynosoma solare Gray, Cat. Liz. Brit. Mus., Ist ed., 1845, p. 229. — Van Den- 



BUUGii, Proc. Cal. Acad. Sci., IV, 1894, p. 45fi. 

 rhrynosoma regale Gihard, Herpet. U. S. Expl. Exp. (Ch. Wilkes), 1858, p. 406. — 



GiKAKi) (Baird), Kept. U. S. Mex. Bouud. Surv., 1859, p. 9, pi. xxviii, figs. 



1-3.— Bocourt, Miss. Sc. Mex., Rept., 1874, p. 235; 1870, pi. xii, lig. 12.— 



BOULENGER, Cat. Liz. Brit. Mus., II, 1885, p. 245. 



Outline of muzzle from above broadly rounded ; in profile abruptly 

 descending without conspicuous angle with front, nor prominent lip 

 border. Nostrils presenting anteriorly only, the nasal plates sepa- 

 rated by a row of scales from the series of the can thus rostralis, which 

 pass externally to them. Temporal region considerably expanded. 

 Posterior superciliary angle produced horizontally. Four occipital 

 horns of subequal length, the external pair slightly divergent, and all 

 directed backward 45°. Each horn depressed, and with the basal por- 

 tions marked with flat tubercles. Only three prominent temporal 

 scales, and all of these produced into horns, which are flat and recurved 

 to the acute tips. The posterior, which is the longest, is not equal to 

 the external occipital. Temporal row of scales not produced to below 

 the orbit, but a row of protuberant scales above it reaches the same 

 point. Scales of top of head flat, tubercular. Two transverse rows 

 of conic scales, of four scales each, posterior to the occipital, the exter- 

 nal of the posterior row the largest. No angle or row of larger scales 

 connecting the posterior superciliaries. A well-developed keystone 

 plate. Infralabials eight on each side, all prominent except tlie ante- 

 rior three, the seventh largest and as long as the anterior temporal 

 spine, the eighth smaller and spiuiform. No subrictal. Enlarged 

 gulars in a single row, with acute apices, the posterior not enlarged. 

 Two rows of spines on the side of the neck, the superior shorter and 

 more bunchy. 



Dorsal scales flat, the median much larger than the lateral, keeled, 

 and with small, round tubercles on the plane portions. Four spaced 

 rows of larger keeled scales on each side of the middle line, those of 

 the external rows much smaller than those of the median. These 

 extremities are scarcely free, but those of the penultimate row are 

 most prominent, especially anteriorly, where the external row is 

 wanting. Lateral fringe continued to above humerus from groin, its 



