LIZARDS. 15 



v?uch a degree of specialization as the Chamafileon. The tongue, 

 eyes, limbs, tail, skin, lungs are modified in a most extraordinary 

 manner to serve special functions in the peculiar economy of 

 these animals. They lead an exclusively arboreal life : each of 

 their feet is converted into a grasping hand, by m-eans of which;,, 



Fig. 11. 



Common Chamseleon. 



assisted by a long prehensile tail, they hold to a branch on which 

 they are sitting, so fast that they can be dislodged only with 

 difficulty. Their movements are slow and awkward on the 



Fi-. 12. 



Hand of Chamseleon. 



ground, and stiil more so in the water, where they are nearly 

 helpless. The tongue (fig. 11) is exceedingly long, worm-like, 

 with a club-shaped viscous end ; they shoot it out with incredible 

 rapidity towards insects, which remain attached to it, and are thus 

 caught. The eyes are almost entirely covered by a thick lid, pierced 

 with a small central hole, and not only can be moved in any direc- 



