REPTILES OF THE PACIFIC COAST. 89 



the direct rays of the sun and must be sought on the 

 shady sides of the granite, into whose crevices it quickly 

 disappears when approached too closely. 



Genus 13. PHRYNOSOMA. 



Phrynosoma, WIEGM., Isis, 1828, p. 367; Batrachosoma, FITZINGER, 

 Syst. Kept., 1843, p. 79 (type coronatum); Anota, HALLOW., 

 Proc. Ac. Nat. Sci. Phila., 1852, p. 182 (type m'callii); Dolio- 

 saurus, GIRARD, U. S. Explor. Exped., Herp., 1858, p. 407. 



The body is very broad, greatly depressed, without 

 dorsal crest, but usually with a lateral fringe. The head 

 is covered with small subequal scales and bears bony 

 spines on the occipital and temporal regions. The tympa- 

 num is either distinct or partially or entirely scaled. The 

 dorsal scales are very irregular in size and shape. Series 

 of femoral pores and one or more transverse gular folds 

 are present. The tail is short. Males have enlarged 

 postanal plates. 



SYNOPSIS OF SPECIES, 

 a. Nostrils opening on or almost on the Hues joining the supraorbital 



ridges with the end of the snout. 



b. Gular scales small, nearly equal-sized; a series of enlarged scales 

 below, but not much larger than, the lower labials; occipital spines 



very short P. douglassii. p. 90. 



b 2 . Several longitudinal series of enlarged pointed gular scales; a series 

 of very large spinose plates below the lower labials; head-spines 

 large, 

 c. Head-shields convex and almost smooth. 



P. blainvillii. p. 91. 

 c 2 . Head-shields flat, with numerous ridges and granulations. 



P. frontale. p. 93. 



a *. Nostrils opening well above the lines joining the supraorbital ridges 



with the end of the snout; a series of very large shields below the 



lower labials; gular scales small, equal or with one row of enlarged 



scales on each side. 



d. One series of small peripheral spines; six to twelve femoral pores; 



no narrow dark median dorsal line P. platyrhinos. p. 98. 



d 2 . Two or three series of peripheral spines; eighteen to twenty femoral 

 pores; a narrow dark median dorsal line. 



P. m'callii. p. 100. 



