72 SAURIA. — CHAM^LEONIDiE. 



One of the most remarkable features in the 

 physiognomy of the Chameleons is the peculiarity 

 of their eyes ; these are large, full, and prominent, 

 entirely covered with the common shagreened 

 integument, except a small round aperture op- 

 posite to the pupil. Unlike all other vertebrate 

 animals, their eyes act independently of each 

 other, so that one may be directed to an object 

 before, while the other remains still, or is looking 

 behind.* 



The head in the Chameleons is large, some- 

 what triangular in outline, and appears set upon 

 the shoulders without the intervention of a neck ; 

 it is very broad across the occiput, where it is 

 sunnounted by an elevated process, greatly deve- 

 loped in some of the species ; ridges also proceed 

 over the eyes, which meet at the muzzle, and are 

 sometimes much prolonged. 



The Chameleons, though constituting but a 

 single genus, comprise numerous species, which 

 are scattered over the warmer regions of the 

 eastern hemisphere, from the south of Spain, and 

 the countries bordering the Mediterranean, to 

 Australia. No species is know^n to exist in 

 America, where the genus seems to be replaced 

 by Anolis and its allies. 



* " These most singular creatures are particularly remarkable for the 

 diminished sympathy of the two sides of their whole frame, one of 

 which may be asleep and the other awake, one of one colour and the 

 other of another, &c. ; the separate movement of their eyes being 

 merel}' another phase of the same phenomenon. Hence it is 

 remarkable, that unlike most other animals, the Chameleon is totally 

 unable to swim, from the incapability of its limbs of acting in due 

 concert."— Blyth's Cuvier^ 278. 



