CHAPTER XIII: THE IGUANAS 



Large Species That May he Recognised by Their Fine Scalaiion atid 



Spine-like Crest 



The true Iguanas are represented in North America by 

 two species that barely come witliin the limits of this work. 

 One inhabits Lower California; the other extends northward 

 from Mexico into southern Arizona. 



Distribution of the Iguanas. — The large and powerful lizards, 

 comprising several genera and known collectively as Iguanas, 

 occur in tropical South America, Central America, Mexico and 

 the West Indies. 



Cyclura and Metopoceros are restricted to the West Indies; 

 Conolophus and Amblyrhynchus occur in the Galapagos Islands; 

 the species of Ctenosaura inhabit Central America, Mexico and 

 the extreme southwestern portion of the United States. The 

 genus Iguana has the most extensive distribution, ranging from 

 Mexico into Brazil. 



General Structure. — Most of the species are of very large 

 size — some growing to a length of six feet. The body is heavily 

 built, the head is large and blunt, with powerful jaws, and the 

 tail is long. Most characteristic is the scalation of the body. 

 The scales are minute, but upon the back is a crest of large, flat 

 spines. 



The Spiny-tailed Iguanas — Genus Ctenosaura: Two species 

 of this genus are the only Iguanas occurring in North America 

 proper. The genus may be popularly defined by the structure 

 of the tail. The appendage is covered with rings or whorls of 

 large, spiny scales. As may be appreciated, such a scalation is 

 really formidable and the tail is employed as an offensive weapon, 

 in dealing quick, lashing blows. The feet are provided with 

 long toes and strong claws and these lizards are very agile climbers, 

 in fact, partially arboreal in habits. 



Ctenosaura is composed of six species. 



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