670 Bulletin American Museum of Natural History [Vol. XL VI 



Phrynosoma platyrhinos Girard 



Phrynosoma platyrhinos Girard, 18.52 pp. 361, 363, PL vn, figs. 1—5; Stejnegek and 



Barbour, 1917, p. 60. 



Range. — Washington and Idaho, south through Utah and Nevada to south- 

 eastern California, northeastern Lower California and southwestern Arizona. 



Lower Californian Records.- — San Felipe, Meek, 1905, p. 12 



A specimen in the Biological Survey collection comes from Pozo 

 San August in (U. S. N. M. No. 35791). This locality extends the range 

 of this form considerably to the south, the only previous record from 

 Lower California being that of Meek from San Felipe Bay. 



Phrynosoma solare Gray 



Phrynosoma Solaris Gray, 1845, p. 229. 



Phrynosoma solare Stejneger and Barbour, 1917, p. 60. 



Range. — Northeastern Lower California, southwestern Arizona and Sonora. 



Lower Californian Records. — Las Animas Bay, Van Denburgh, 18946, p. 456. 



The distribution of P. solare is remarkable for the wide gap between 

 the Lower Californian record (opposite Angel de la Guardia Island) and 

 the area of relative abundance of this species at the border of the Mexi- 

 can Plateau in Arizona. It appears to be absent from the Colorado 

 Desert, and thus forms one of the best examples of what I have called 

 attention to (above) as peripheral distribution, bordering the Colorado 

 Desert. 



Key to the Species of Phrynosoma in Lower California 



1. A single marginal (lateral) fringe of elongate scales 2. 



Two or three complete marginal fringes 3. 



2. Nostrils within the lines of the canthi rostrales P. platyrhinos. 



Nostrils on the lines of the canthi rostrales P. cerroense. 



3. Three closely set lateral fringes; tail flattened. (Not recorded from Lower Cali- 



fornia, but probably entering the northeastern area.) P. m'callii. 



Two lateral fringes; tail round distally 4. 



4. Four large subequal occipital spines in line with the temporals P. solare. 



Occipital spines unequal, not in line with the temporals 5. 



5. Subrictal spine broadly expanded at base, its anterior border overlapping the 



last spine of the sublabial series 6. 



Subrictal not overlapping the last of the sublabials, nearly in line with them ... 7. 



6. Scales of mid-dorsal line keeled, pointed and strongly imbricate; scales of front 



rugose P. nelsoni. 



Scales of vertebral line smaller, rounded and less imbricate; scales of front 

 convex and smooth .P. blainvillii blainvillii. 



7. No slender elongate postrictal spine P. coronation. 



A slender elongate postrictal spine, about as long as the subrictal 8. 



8. Lower of the two lateral fringes weak; occipital spines slender P. jamesi. 



Lower lateral fringe strongly developed; occipital spines short and stout. 



P. schmidli. 



