94 [June, 



Wiegmann, is unicolor ; and the plates upon the head cannot be said to 

 he ruguloso carinatis, for they are for the most part smooth in bi-seriatus. 

 It wants the white lateral line beneath the spots which is observed in scalaris, 

 Wiegmann. The arrangement of the plates upon the head appears to characterize 

 this species very well, being uniform, with unimportant exceptions, in all the 

 specimens brought by Dr. Heermann. 



Var. A. azureus. Body uniformly blue above, mingled with brown, the 

 the blue color predominating; on the sides greenish with a metallic lustre ; head 

 brownish above ; two large blue blotches upon abdomen, one on each side ; rest 

 of under surface silvery white with bluish tints, especially about the chin ; scales 

 large and strongly carinated, not denticulated posteriorly; tail stout at the base, 

 much less tapering than in bi-seriatus; the plates of the head correspond pre- 

 cisely with those of the latter animal. 



Dimensions* Length of head, neck and body to vent, 3 2-8ths inches ; of tail 

 3 5-Sths inches ; of anterior extremities 1 inch ; of anterior foot to extremity of 

 longest toe 6-8ths inch ; of posterior foot to extremity of longest toe 1 2-8ths 

 inch ; total length 6| inches. 



Habitat. Associated with bi-seriatus. 



Var. B. variegatus. Body light ash color, with transverse brownish bands 

 and markings coalescing with each other, so as to give the whole a marbled 

 appearance ; head above ash color mingled with brown ; extremities ash color, 

 with transverse bands of brown ; under surface silvery grey without bluish spots 

 or blotches ; 17 femoral pores, remarkably large ; tail stout, thick at the base. 



Dimensions. Length of head neck and body 4h inches ; greatest breadth of 

 head 1 inch ; length 1 inch ; tail mutilated, circumference at base 1 2-8ths inch ; 

 length of anterior extremities If inch ; of loot to extremity of longest toe f inch ; 

 of posterior extremity 2 inches ; of foot, posteriorly, to extremity of longest toe 

 1 inch. 



Habitat. Same. 



CNEMIDOPHORUS, Dum. and Bib. 



Gen. Char. Nostrils in the nasal plate near its posterior border ; two supero- 

 nasals ; palate without teeth, with a shallow, triangular notch, posteriorly ; 

 scales smooth. (Dum. and Bibron.) 



Cnemidophorus undtjlatus,* nob. 



Sp. char. Body of moderate size ; tail very long ; head brownish above ; upper 

 part of body with three or four longitudinal bands of black with irregular mar- 

 gins ; interspaces yellowish, with a tinge of red in some specimens ; sides mar- 

 gined with black and white or light yellow ; tail black and light yellow, present- 

 ing numerous transverse rows of rhomboidal carinated scales ; upper part of 

 extremities same color as sides of body; under surface silvery grey, with a 

 number of minute black spots upon the abdomen, throat and chin ; tail round, 

 moderately thick at base, tapering to a point ; 20 pores very distinct ; 8 rows 

 scales upon the abdomen. 



Dimensions. Length of head 1 inch ; greatest breadth posteriorly half an inch ; 

 of head, neck and body 3k inches ; of anterior extremities % inch ; of foot to ex- 

 tremity of longest toe half an inch; of posterior extremities 1 inch ; of foot to 

 extremity of longest toe 1 inch ; of tail 7 inches ; total length 111 inches. 



Habitat. Near Fort Yuma, in San Joachim Valley. 



Gen. observ. Cnemidophorus perplexus, according to Profs. Baird and Girard, 

 has seven longitudinal yellowish lines along the back ; in all the specimens above 

 described, five in number, there are but four. Profs. Baird and Girard state that 

 in some specimens of Cnemidophorus tigris, " four longitudinal yellow stripes 

 may be seen extending from the occiput to the base of the tail, and occasionally 

 a little distance on the latter. In the young state the black patches predominate, 

 unite, and form as it were the ground color, and the yellow constitutes irregular 

 small spots." Vide Sta?isbury's Report, Appendix C. p. 339. 



From the undulating longitudinal dark lines along the back. 



