78 REPTILES AND BIRDS. 
The under part of the body is furnished with a single row of large 
plates. The Rattlesnake owes its name to a remarkable peculiarity 
in its structure ; the extremity of the tail is furnished with horny 
cells, articulated one into the other. When the animal is irritated it 
causes its tail to vibrate, which produces a sound like the dry husks 
Fig. r9.—Northern Rattlesnake. 
of beans which still retain their seeds being shaken by the wind, thus 
giving warning of the proximity of this terrible enemy. The sibilant 
rattle of these appendages is not very loud, but it may be heard /en 
paces off. : 
Rattlesnakes feed on small mammals, or upon other reptiles. 
They are oviparous ; and, for some time after they are hatched, the 
young are said to seek a refuge in the mouth of their mother. W ood- 
land or prairie are selected by them, according to the species they 
