XIV INTRODUCTION. 



with the noose, the arrow, or the gun. The range of Basiliscus also extends 

 northward into Southern Mexico. Crested on head, back, and tail, slender 

 and spider-like in build, in novelty of appearance it rivals the Ghlamydo- 

 saurus. In some genera, as Polychrus and Sphaerqps, the skin is to such 

 an extent unprotected by the scales or granulations as to allow the tran- 

 sient color variations to be very noticeable. 



Nine or ten genera of the family are found north of Central Mexico. 

 Only one, in a single species, Sceloporus undulatus, occurs east of the Mis- 

 sissippi. The undulated lizard ranges northward from the Gulf as far as 

 Southern Illinois and Maryland. It is common in parts of Kentucky and 

 Virginia. Phrynosoma, a viviparous genus, ranges from Mexico to Dakota; 

 it contains nine species, none of which appear East of the plains. One, 

 P. douglassii, is common in Southern Dakota. Early in August the female 

 gives birth to about eight young ones. Ants appear to form their principal 

 food, though they are not by any means limited to them. They are vul- 

 garly called "Horned Toads." The- subfamily Anoliidce is represented in 

 the Southern States by a common Saurian, the little greenish, flat-crowned, 

 slender-tailed, goitred lizard of the trees and bushes, sometimes called 

 "Chamaeleon" or "Scorpion." 



The Lacertidce belong to the old world. They are diurnal land lizards, 

 with polygonal symmetrically-arranged shields on the head, slender, forked 

 exsertile tongues, eyes provided with lids, nonimbricate scales, four limbs, 

 and long fragile tails. They are the common lizards of Europe. The 

 genus Zootoca is viviparous. 



The Teiidce are Saurians of the Western Hemisphere. Their heads are 

 covered with angular shields; and their tongues are free, notched, and 

 exsertile. The only genus representing the family in the United States 

 contains the slender, short-limbed, six-lined lizard Cnemidophorus sexlineatus, 

 of the South. Species of this genus are more numerous in the Rocky 

 Mountain district, from Montana to Mexico. Teius contains several large 

 South" American species; they are the "Tupinambis" of the Amazon basin. 

 A young individual has the teeth fixed on the inside of the jawbone, but 

 as he grows older the bone surrounds them more and more. 



The Seines, Scincidce, generally have fusiform or subcylindrical bodies, 

 and are covered with glossy scales, which are either smooth, keeled, or 

 grooved. The limbs are short, the body and tail rather long. In some 

 there are no limbs, Any ids; in others there are two, Ophiodes; and in the 



