82 CROTAPHYTUS COLLARIS. 



form. There is a range of nineteen femoral pores mider each thigh, well 

 developed, and with a row of scales larger than common before them. 



The tail is more than twice the length of the body, thick, and flattened at 

 its base, but soon tapers, becomes cylindrical and very small; it is covered with 

 oblong-quadrate plates, larger than those on the body, verticillated, smooth on 

 the anterior half, carinated on the posterior to the tip. The vent is transverse, 

 rather semicircular, with a depression behind it, and a row of larger scales. 



Colour. The head above is uniform dusky brown, tinged with a greenish or 

 purplish hue. The neck beneath is pale; "at the sides it is fulvous, more or less 

 varied with bright vermilion-red" in life, with two deep black bands extending 

 across the shoulders between the anterior extremities, and a broad yellowish- 

 white band between them. The body above is slate-colour, tinged with green 

 or purple, and with five or six dusky, broad bands, tinged with purple, alternating 

 with narrow fulvous bars, each with a series of yellow spots, which are also 

 scattered in the darker parts of the back. The bands on the body disappear 

 altogether in the very old animal, and the whole superior surface is then of a 

 uniform slate-colour, tinged with purple, and studded with light coloured spots. 

 The sides are greenish-yellow; the abdomen is silver-white in the preserved 

 specimen, and clouded at the throat. The extremities and tail are marked with 

 alternate bars of dusky and fulvous. 



Dimensions. Length of head, 1 inch 2 lines; breadth of head over temporal 

 muscles, 1 inch 2 lines; length of body to vent, 3 inches; of thigh, 1 inch; of leg, 

 1 inch 1 line; of tarsus and toes, 1 inch 8 lines; length of tail, 8 inches; total 

 length, 12 inches. 



Habits. I am imacquainted with the habits of this reptile. 



Geographical Distribution. It inliabits the south-western portions of the 

 United States, as Arkansas and Louisiana, near the confines of Texas. 



