i6 2 NATURE-STUDY 



of its cage. Give it some large insects and frogs to eat. It is 

 interesting to see it eat frogs, which are generally seized and 

 eaten alive. The snake does not chew its food, but swallows 

 it whole. By a curious dislocation of the jaws at the back, 

 allowing the mouth to distend widely, it can swallow a frog 

 of larger diameter than itself. The snake secretes a large 

 amount of saliva, which flows over the frog and makes it 

 more easily swallowed. The two halves of the lower jaw 

 are hinged together in front and are separately movable 

 backwards. This arrangement is very useful in swallowing 

 small animals. 



Perhaps another interesting habit of the snake will be ob- 

 served, the shedding of the skin. Our skin is constantly 

 coming off in minute scales or shreds, rubbed off by the 

 clothing and in the bath, but it is being renewed con- 

 tinually from beneath. So it is with snakes, except that peri- 

 odically they shed their skin whole. Sometimes a very per- 

 fect sheath is left in the shedding. 



Snakes' eyes are always staring, for they cannot close or 

 move them. They are covered with a transparent skin and 

 have no lids. 



Snakes live in burrows, crevices, and under litter, or in the 

 holes left in the earth by decayed tree roots. 



Non- venomous snakes, on the whole, are useful creatures, 

 and destroy insects, frogs, and small mammals, such as mice, 

 moles, shrews, rats, etc. On the other hand, they do more or 

 less harm in killing the useful toad, and in destroying the 

 eggs and young of birds. 



There are many common species of snakes in this country. 

 As stated above, the only poisonous snakes are the rattle- 

 snake, copperhead, moccasin, and the little coral snake. 



