CHAMELEON. FAMILY GECKOTID^l. 557 



to understand, however, by what arrangement this can be 

 effected ; or how all the shades of colour, which the Chameleon 

 presents, can be given by the mixture of two only. These 

 curious animals are arboreal in their habits ; traversing the 

 twigs and branches in a slow and cautious manner, with the aid 

 of the grasping powers of the feet and tail ; and occasionally 

 darting out their tongues at insects that come within their reach, 

 with such rapidity that the movement is scarcely perceptible. 

 They are very inanimate in their appearance, often remaining in 

 precisely the same position for many hours together ; and they 

 can exist for several months without food. The lungs are large, 

 and are connected (as in Birds) with air-cells that lie among the 

 muscles and beneath the skin ; hence the appearance of the 

 animal varies greatly, according as these cavities are full or 

 empty, being sometimes full and bloated, and the next minute, 

 lean and shrunken. 



493. The GECKOTID^E, or Geckos, are Lizards of small size, 

 but of repulsive aspect ; their bodies being flattened, and their 



'Fin. 331 GECKO. 



colour lurid. Many of the species are considered as poisonous 

 by the inhabitants of the countries in which they are found ; 

 and some even assert that they infect every substance over which 

 they walk ; but both these opinions are, to say the least, very 

 doubtful. From the peculiar structure of their toes ( 467), 

 they are capable of running along the smoothest surfaces, of 

 creeping up walls, and even of traversing ceilings, like a fly, 



