1911] Bryant: Horned Lizards of California and Nevada 23 
EXTERNAL CHARACTERISTICS 
Diagnostic Characters: Head broader than long; nostrils at 
the end of the superciliary ridge; occipital horns very short, 
being in some cases mere tubercles; supratemporal horns pro- 
jecting farther posteriorly than the occipital; head plates irregu- 
lar in size and shape, and usually convex and granulated; sub- 
labials not much larger than infralabials, the last three or four 
Fig. C. Skull of Phrynosoma douglassi douglassi (Zool. Dept.).  dent., 
dentary; fron., frontal; jug., jugal; max., maxillary; nas., nasal; nasal op., 
nasal opening; occ. h., occipital horn; orb., orbit; par., parietal; pin. for., 
pineal foramen; prefron., prefrontal; premaz., premaxillary; postorb., post- 
orbital; supraoce., supraoccipital; supratemp., supratemporal; supratemp. 
op., Supratemporal opening; temp. h., temporal horn. X 2. 
enlarged and pointed; a conical rictal scale present; gular scales 
small and equal in size; body with one row of peripheral spines ; 
back and tail with several rows of large, keeled, spiny scales set 
among smaller scales and granules; abdominal scales small and 
smooth; tail slender and rounded toward tip; tympanum usually 
visible but sometimes covered with seales; femoral pores in long 
series almost meeting medially. 
Description: The horns are very rudimentary, reduced to 
blunt, conical tubercles, and flattened and grooved, those of the 
supratemporal elements projecting beyond those of the occipital 
region (pl. 3, fig. 7). The two occipital spies are widely sep- 
arated at the base. An enlarged scale alone gives evidence of 
