38 University of California Publications in Zoology [Vou.9 
Phrynosoma blainvillei frontale (Van Denburgh) Bryant 
California Horned Lizard 
Phrynosoma blainvillei Gray (1839), p. 96, pl. 29, fig. 1. 
Phrynosoma coronata Holbrook (1842), pp. 97—100, pl. 13. 
Phrynosoma frontalis Van Denburgh (1894), pp. 296-298. 
Phrynosoma frontale Van Denburgh (1897), pp. 93-98. 
EXTERNAL CHARACTERISTICS 
Diagnostic Characters: Head spines usually smaller and nar- 
rower than those of P. blainvillei blainville: and very much 
erooved; small interoecipital spine present; nostrils on the lne 
joining the superciliary ridge with the end of the snout; snout 
not separated from frontal region by a prominent angle; tem- 
poral spines three to six on each side; head plates nearly equal- 
sized, flat, and covered with numerous ridges and granulations; 
sublabials, spinose and continued posteriorly by small plates; 
below the rictus a large, broad infrarictal spine followed by a 
smaller conical one; enlarged gular scales in three or more double 
rows with apices pointing outward; peripheral spines in two 
widely separated rows, the upper being the largest; back and 
tail covered with large scattered scales, which are strongly keeled 
and tubercular, set among smaller scales and granules; ventral 
scales smooth; tail conical and fringed by a row of widely sep- 
arated trihedral spines; tympanum not covered with scales; 
femoral pores in long series (12-18). 
Description: The two occipital horns and the interoecipital 
are usually narrower and smaller than those of P. b. blainvillei 
and the former are very much grooved (pl. 5, fig. 11). The horns 
of the occipital region are on a higher level than those of the 
supratemporal region. The nostrils are on the line joining the 
superciliary ridge with the end of the snout. The snout is sep- 
arated from the frontal region by a very obtuse angle. Two rows 
of peripheral spines surround the body, the smaller lower row 
being separated from the upper by several rows of scales. Three 
longitudinal rows of enlarged, pointed scales with apices outward, 
the inner rows being the smallest, are to be found on each side 
