OCR Text |
Show APPENDIX C.- REPTILES. 345 the scales to which it makes allusion becomes now a generic character. Thus the species included in the genus Uta are, generally speaking, of a smaller size than the scelopori proper. UTA BTANSBURIANA, Baird and Girard. PL. V. Pio. 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 m 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, Crotaphytut, and Holbrookia; 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 Holbrookia 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, composed of scales a little larger than the subgular ones. The auditory aperture is moderate, surrounded by irregular folds of the skin which extend under the throat; from its anterior edge pro- |