1906.] IN MEXICAN LIZARDS. 335 



C. semifasciatus with, C. sericeits without frenocular. The dis- 

 tinctly feeble collar, only polygenes on the forearm, and the high 

 number of pores, combined with the peculiar dorsal pattern, 

 justify us to treat these specimens as a distinct subspecies, 

 especially since they differ so I'emarkably from the other kinds of 

 Gnemidophorus of closely neighbouring districts, e. g., C. melano- 

 sthetus of Parras, C. gidaris gidaris and var. meeki of Monterey, (fee. 



Onemidophorus septemvittatus Cope. 



Based upon one female specimen from Eldorado Oovuity, 

 California. Length 110 mm., which, for a female, indicates a 

 very large kind of Gnemido'phorus. 



Supraoculars 4. Collar composed of large scales. Humerals in 

 6 rows. Posterior side of forearm, according to figure, with 5 

 mostly very large scutes in a row, surrounded by granules. 

 Femorals in 7 rows. Pores 16/18. 



Coloration. — Under parts all yellowish, with a few black specks 

 on the sides of the throat. Upper parts light olivaceous brown, 

 with 7 longitudinal broad black stripes, three on each side and 

 one in the middle, &c. From Cope's long description I gather 

 the following, if translated into the language employed in the 

 present paper : — There are 6 pale stripes, separated by black 

 fields and a black mid-field. Towards the lower back and upon 

 the rump the stripes 2 and 3 ai'e broken into spots by the gradual 

 encroaching of the black pigment from the neighbouring fields, 

 which themselves have but few and small field-spots, restricted to 

 the anterior half of the body.. 



To judge from this solitary specimen, it seems to belong rather 

 to the G. communis of the gidaris-gvo\\]i. 



Cnemidophorus scalaris Cope. (Text-figs. 68 & 76.) 



19 specimens fi-om Chihuahua, near the City. Field Museum 

 of Natural Histoiy. 



Length 50-95 mm. ; 95 mm. only one male, while three or four 

 other males come near 90 mm. This is consequently a small and 

 slender species, inhabiting the arid plains with their spai-se 

 vegetation of Mesquite and Fouquieria shrubs. Yuccas and 

 Opuntias. Hitherto recorded only from Chihuahua. 



Supraoculars 4, mostly with only one row of elongated granules 

 behind. 



Collar sharply marked and composed of moderate scales. In 

 only one specimen is the posterior margin of the fold formed 

 by a complete row of granules, while in one other the granules 

 are restricted to the lateral third of the collar. 



Himierus. — 3 or 4 large rows of scales cover the front, then 

 follow 2 or 3 shorter and somewhat smaller rows ; about 6 in 

 all, or only 5, in which case the first or first and second rows are 

 extra large. But 8 rows cannot possibly be counted in these 

 specimens, as stated by Cope for his ssalaris from Chihuahua. 



