LIZARDS. 113 



to them, as shown by their great abundance and their 

 varied kinds at Para and in the Aru Islands places 

 which are nearly the antipodes of each other, but which 

 both enjoy the fine equatorial climate in perfection, and 

 are alike pre-eminent in the variety and beauty of their 

 insect life. 



Three peculiar forms of lizard may be- mentioned 

 as specially characteristic of the American, African, and 

 Asiatic tropical zones respectively. The iguanas of 

 South America are large arboreal herbivorous lizards 

 of a beautiful green colour, which renders them almost 

 invisible when resting quietly among foliage. They 

 are distinguished by the serrated back, deep dew-lap, 

 and enormously long tail, and are one of the few kinds 

 of lizards whose flesh is considered a delicacy. The 

 chameleons of Africa are also arboreal lizards, and they 

 have the prehensile tail which is more usually found 

 among American animals. They are excessively slow in 

 their motions, and are protected by the wonderful power 

 of changing their colour so as to assimilate it with that 

 of immediately surrounding objects. Like the majority 

 of lizards they are insectivorous, but they are said to be 

 able to live for months without taking food. The 

 dragons or flying lizards of India and the larger Malay 

 islands, are perhaps the most> curious and interesting of 

 living reptiles, owing to their power of passing through 

 the air by means of wing-like membranes, which stretch 

 along each side of the body and are expanded by means 

 of slender bony processes from the first six false ribs. 

 These membranes are folded up close to the body when 

 not in use, and are then almost imperceptible ; but when 

 open they form a nearly circular web, the upper surface 



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