in ANIMAL LIFE IN THE TROPICAL FORESTS 303 



inhabit the tropics, and they probably increase in numbers 

 towards the equator. A rich vegetation and a due propor- 

 tion of moisture and sunshine seem favourable to them, as 

 shown by their great abundance and their varied kinds at 

 Para and in the Am islands places which are nearly the 

 antipodes of each other, but which both enjoy the fine equa- 

 torial 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 of which is generally zoned with red 

 or yellow in a highly ornamental manner. By means of this 

 parachute the animal can easily pass from one tree to another 

 for a distance of about thirty feet, descending at first, but as it 

 approaches its destination rising a little so to reach the tree 

 with its head erect. They are very small, being usually 

 not more than two or three inches long, exclusive of the 

 slender tail ; and when the wings are expanded in the sun- 



