VERTEBRATA: REPTILIA. 553 



is naturally a sluggish animal, but it catches its food, consist- 

 ing of insects, by darting out its long, fleshy, and glutinous 

 tongue an operation which it effects with the most extra- 

 ordinary rapidity. 



The tail in the Chameleons is round and prehensile, the 

 body compressed, and the skin like shagreen. The tongue' 

 is long, vermiform, club-shaped in front, and very extensile. 

 The toes are adapted for the arboreal life and scansorial habits 

 of the animal, being so arranged as to form two equal and 

 opposable sets. The lungs are excessively voluminous. The 

 Chameleons are exceedingly sluggish and slow in their move- 

 ments, and are confined to the warmer parts of the Old 

 World. 



The last group of living Lizards which requires notice is 

 that of the Rhynchocephalia, a group comprising only the 

 curious genus Hatteria or Sphenodon, which is so aberrant in 

 its characters that this section may well be regarded as a sub- 

 order of Lacertilia. Only one species (If. punctata) of this 

 genus is known, and it inhabits New Zealand. 



In this singular form (fig. 307) the vertebrae are amphiccelous, 



Fig. 307. Side view of the skull of Hatteria punctata, the lower jaw being removed. 

 (After Gunther.) 



and some of the ribs bear " uncinate processes " similar to those 

 of Birds. The quadrate bone is not movable, and is united by 

 suture with the skull. The teeth are completely amalgamated 

 by anchylosis with the jaws, and are developed in the mandible, 

 praemaxillae, maxillae, and in a longitudinal series upon the 

 palatine bones. The praemaxillary teeth are two in number, 

 and are of large size and scalpriform in shape. The serrated 

 edge of the mandible is received in the groove between the 

 palatine teeth and the cutting edges of the maxillae, the alveolar 

 borders of which are hard and as highly polished as the teeth 

 themselves, the function of which they discharge when the 



