3 02 



REPTILES. 



tongue. The food of the chameleon consists of insects, and it will remain 

 motionless, stationed upon a branch, until the unconscious prey comes within 

 reach, when in a moment the tongue is darted forth, and the insect is caught 

 and swallowed. Their power of changing colour is wonderful, accurately 

 imitating the tints of the leaves and branches around them; so that their 

 presence is not discoverable except upon close inspection. 



The Crocodiles (Crocodifas), sometimes classed as a distinct Order under 

 the name of Loricata, are the giants of the reptile race, some of them attain- 

 ing the length of twenty-five feet ; and as they are strong, ferocious, and cun- 

 ning, they may rank among the most formidable animals. In their general 

 form they agree with the lizards, but they are distinguished by several im- 

 portant characters. 



FIG. 330. CROCODILE. 



Of these, the most tangible and obvious is that the whole back part of the 

 neck, body, and tail is clad with distinct series of bony plates, embedded, 

 as it were, in the substance of the skin, and covered externally with a thick 

 cuticle. These dermal bones are exceedingly strong, and they altogether form 

 a panoply of defence capable of resisting the attacks of the most powerful 

 enemies. The bones of the head in the crocodile are more consolidated than 

 those of most reptiles ; the lower jaw is prolonged behind the base of the skull, 

 and this structure causes the upper jaw to seem moveable. There is in each 

 jaw a single row of teeth, which are conical in form. A cavity at the root of 

 each tooth serves as a case or sheath for the germ of the tooth destined to 

 replace it; and each being thus gradually pushed out by a successor ready to 

 supply its place, the mouth of the crocodiles presents at all ages its formidable 

 array of pointed teeth in undiminished number. The tongue is flat, and free 



