THE REPTILES 193 
adapt themselves to their new surroundings, become tame, 
and feast on flies, ants, and other insects, which they cap- 
ture by the aid of their long tongue. The horned toads 
are perfectly harmless creatures, but when irritated some- 
times perform the remarkable feat of spurting a stream of 
blood from the eye toward the intruding object for a dis- 
tance of several inches. This has been regarded by some 
as a zoological fable; but there are many who have watched 
the horned toad in its natural state and in captivity, and 
they assure us that it is a fact. 
In the hot deserts of Arizona and Sonora is another 
peculiar species of lizard known as the Gila monster (Helo- 
derma) (Fig. 115), having the distinction of being the only 
poisonous lizard known. Further protection is afforded 
by bony tubercles on the head and by scales over the 
remainder of the body, all of which are colored brown or 
various shades, of yellow, giving the animal a peculiar 
streaked and blotched appearance. 
182. Distribution of the snakes—The snakes are much 
more common than the lizards. All over the United States 
one meets with them, especially the garter- or water-snakes. 
Of less wide distribution are the black-, grass-, and milk- 
snakes, and a number of less known species, all of which 
are perfectly harmless and often make interesting pets. 
Some of them when cornered show considerable temper, 
flatten the head and hiss violently, and Amitate poisonous 
forms, but venomous snakes are comparatively few in num- 
ber in northern and eastern United States. In the south- 
ern portions of the country they become more abundant. 
Along the streams and in the swamps the copperheads, and 
especially the water-moccasins, often lie in wait for frogs 
and fish. Both these species are especially dreaded, as they 
strike without giving any warning sound, but the name 
and bad reputation of the moccasin is often, especially in 
the South, transferred to perfectly harmless water-snakes. 
On higher ground are the rattlesnakes (Crotalus), once 
