GECKOS, LIZARDS, AND CHAMELEONS. 99 



Since then several other Australian lizards, many 

 of the American Teguexius, and Old - World 

 Monitors have also been shown to adopt, for 

 short distances, the same method of escape. 

 It has been contended that this habit has been 

 directly inherited from those extinct giants, 

 the Dinosaurs (chap, ix.), but of course this view 

 cannot be seriously entertained. 



Although the number of different kinds of 

 lizards which have their abode in the tree-tops 

 is legion, there can be no donbt but that this 

 habitat is not to be regarded as their ancestral 

 home. They are, as their structure shows, 

 essentially terrestrial animals. Furthermore, it 

 is interesting to notice that, with the vast 

 majority of species, no special adaptation to 

 an arboreal mode of life has taken place. 

 Strangely enough, the struggle for existence 

 seems to have prevented specialisation in this 

 direction in all save a few exceptional cases. 

 The majority of these tree-dwelling species 

 seem, on the contrary, to be exceptionally 

 versatile. Climbing with ease, leaping with 

 marvellous precision, and escaping pursuit, 

 when necessary, by daring plunges into the 

 rivers, and thus avoiding capture, by swimming 

 to a place of safety. 



The Common Iguana (Iguana tuberculata) may 

 serve as a case in point. This species inhabits 

 the forests of South and Central America, choos- 

 ing those trees which border and overhang creeks 

 and rivers. When alarmed, no matter what the 

 height of the tree, they jump boldly down into 

 the water below. 



