CROCODILIANS, LIZARDS, AND SNAKES. 425 



free apices directed posteriorly, without a circle of scales around their 

 bases. A marginal fringe of flat lanceolate scales, extending from 

 anterior to tlie groin to above the shoulder, and a lower marginal series 

 of much smaller scales along the middle part of the lateral border. 

 Between the superior row and the larger dorsal scales are several lon- 

 gitudinal folds, surmounted each with a series of oval keeled scales 

 larger than those that surround them. Superior surfaces of fore limb 

 with large keeled mncronate scales, mixed with a few of smaller size. 

 Upper surface of posterior limb with small scales, and scattered large 

 keeled spinous scales. Tail with a lateral fringe of large, flat, lanceo- 

 late scales to near the extremity; the superior surface with irregular 

 pholidosis of flat keeled scales, some with projecting apices. Scales 

 of all the inferior surfaces smooth, except those of the humerus and 

 tibia, which are weakly keeled. Keeled scales of front of humerus not 

 continued across the middle line. 



Extended hind leg reaching to axilla or middle of humerus. Tail 

 a little over twice as long as head without horns. Femoral pores 

 fifteen in each row, which is separated from the opposite one by a wide 

 interspace. 



Measurements (San Diego, California). — Total length, 147 mm. ; length 

 to vent, 92 mm.; length to gular fold, 20 mm.; length of head with 

 occipital horn, 32 mm.; length of head without occipital horn, 22 mm,; 

 width of head at temporal region, 23 mm.; length of fore leg, 43 mm.; 

 length of fore foot, 26 mm.; length of hind leg, 57 mm.; length of hind 

 fitot, 23 mm. 



Color above light brown ; head light-yellowish brown, without darker 

 markings. Temporal spines light red or pink, occipital horns mahog- 

 any brown, with reddish apices; the ridges darker than the grooves. 

 Lateral nuchal brown spots large, well sej)arated. Between these and 

 the groin on each side three dusky brown bilobate cross bands, 

 obscurely defined anteriorly; in young specimens with imperfect pos- 

 terior light border. Inferior surface of limbs and tail with a few obscure 

 crossbars. Inferior surfaces immaculate, except a few obscure dusky 

 spots on the abdomen in some individuals. 



This species inhabits the southern part of the Pacific district, that 

 is, California south of San Francisco Bay, and the upper part of the 

 peninsula of Lower California, at least as far south as San Thomas 

 (Van Denburgh). In the northern part of the Pacific district its place 

 is taken by the P. douf/lassii. No other species occupies the range of 

 the F. hlainvillei. 



Mr. Van Denburgh states that specimens from the northern part of 

 this range have the head scales less convex and more rugose than in 

 those from the southern ])()rtion of it, and he proposes to regard the 

 former as a distinct species, under the name of P. frontale. No other 

 character is advanced by Mr. Van Denburgh, so that specific distinct- 

 ness can scarcely be admitted. Perhaps a race is indicated, Irs value 

 appears, however, to be problematical, as specimens in my possession 



