196 NATURAL HISTORY. 
CHAPTER XIX. 
REPTILES—continued. 
f 323. Tue order of Lizards comprises a great variety 
of animals exhibiting some of the characteristics of the 
Crocodile tribe mingled with some which are peculiar to 
the Serpents. They resemble the former in their long 
body, tapering off in a tail; but, instead of the large bony 
plates of the Crocodiles, they have the small scales of the 
Serpent tribe; and, though they usually have four feet, 
in some of them there is but one pair, and in others the 
feet are so short, and so covered up by the skin, that the 
animal looks entirely like a snake. There is much vari- 
ety in the habits of this order. Some are more or less 
aquatic ; some are terrestrial, digging holes in the ground 
as places of retreat; and others are wholly arboreal. 
Their colors have a relation to their habits; the ground 
Lizards being brown and speckled, while the tree Lizards 
have bright colors, green predominating. When the sun 
wakes up the latter to activity, their quick movements 
make the play of their brilliant colors very beautiful. 
The principal families in this order are the following: 1. 
The Chameleons. 2. The Geckos. 3. The Iguanas. 4. 
The Monitors. 5. The true Lizards. 6. The Snake Liz- 
ards. 7. The Naked-eyed Lizards. 
324. The Chameleons are distributed through the 
warmer parts of the Old World, but are not found in the 
New. They are distinguished from the other families 
by very marked peculiarities. Their bodies are flattened 
sideways, and there is a sharp ridge along the length of 
the back. Of the five toes of each foot, two are directed 
backward, so that the animal can grasp firmly the branch- 
es of trees in climbing. Its tapering tail is also prehen- 
sile, and is used in its arboreal mode of life as the Spider 
