APPENDIX C. — REPTILES. 345 



the scales to which it makes allusion becomes now a generic charac- 

 ter. Thus the species included in the genus Uta are, generally 

 speaking, of a smaller size than the scelopori proper. 



Uta stansburiana, Baird and Girard. 



Pl. V. Fig. 4-6. 



Spec, char.— Tail slender, elongated, and conical, provided with large scales 

 arranged in verticils ; a subgular fold in addition to the pectoral one. 



This species is one of the handsomest and most graceful among 

 the small saurian forms peculiar to North America. In its general 

 aspect it recalls to mind the cnemidophori, having, like the latter, 

 the body covered with small polygonal scales, while on the tail 

 the scales are large, elongated, and verticillated. The proportions 

 in length between the body and tail, and the fold under the throat, 

 are likewise similar in both Cnemidophorus and Uta. But when we 

 compare the shape and structure of the head in the two, we detect 

 differences which are not merely generic, but cause them to belong 

 to different families. The upper surface of the head is covered 

 with small and polygonal scales, as in Sceloporus, CrotapJiytus, and 

 Holhroohia; its shape is rather rounded than conical or elongated, 

 and is broad and flattened, while it is narrower and higher than 

 broad in cnemidophori and allied genera. The body is subfusi- 

 form, the tail slender, conical, and nearly one and a-half times the 

 length of the body and head together. 



The occipital plate is polygonal and comparatively large; three 

 or four superciliaries, the vertical and frontal plates, are a little 

 larger than the many others by which they are surrounded. 

 The nostrils are very conspicuous, and approximated to the end 

 of the snout; they are situated interior to the prolongation of the 

 superciliary ridge, and composed of elongated and narrow plates. 

 The rostral plate is narrow, and is scarcely to be seen when viewed 

 from above, but much more conspicuous than in Holhroohia when 

 looked at in front. The plates lining the margin of the jaws are 

 quadrangular, elongated, and much narrower on the upper than 

 on the lower jaw. Under the chin, three or four pairs of polygonal 

 scales are considerably the largest. Between the latter and those 

 on the margin of the lower jaw two other rows may be seen, com- 

 posed of scales a little larger than the subgular ones. The audi- 

 tory aperture is moderate, surrounded by irregular folds of the 

 skin which extend under the throat; from its anterior edge pro- 



