IGUANIDAE 



529 



most species can change colour to a great extent. More than a 

 hundred species are known, of which we mention only one, very 

 common in the Southern United States. 



A. carolinensis of the South-Eastern United States and of 

 Cuba is beautiful golden green on the whole upper surface ; the 

 sular sac becomes vermilion when inflated ; when flaccid, it is 

 white with occasional red lines and spots. The under parts are 

 white. In cold weather and in confinement this little lizard, 

 which is scarcely 6 inches in length, appears dark brown, 

 sometimes with a white line along the back. The changes of 

 colour are very sudden. They are ' thoroughly arboreal, leaping 

 from leaf to leaf like Tree-frogs. 



^=, ANCUIDftE. IHIl ISUANIDAE. i:-- ZONURiDAE. 



Fig. 130.— Map showing the distribution of Anguidae, Iguanidae, and Zonuridae. 



In AnoUs, Polychrus, Hoplurus, Ghalarodon, Liosaurus, and a 

 few others, the posterior ribs are much elongated and imbedded 

 in the abdominal muscles, often reaching the medioventral line, a 

 feature elsewhere known in the Geckos only. 



Polychrus. — The body is laterally compressed, covered with 

 small scales, but devoid of crests. The digits are likewise com- 

 pressed, with keeled lamellae on the under surface and with 

 four large scales at the base of each claw. Both sexes have 

 femoral pores. The male possesses a small gular sac. A few 

 species in Tropical America. 



P. marmoratus in South America, where it is often called the 



Chameleon on account of its power of changing colour. The tail 



is nearly three times as long as the head and body, and is covered 



with keeled scales. The general colour of this arboreal creature, 



VOL. vin 2 ^ 



