NATURAL HISTORY. IV 3 



" The tres, devouring caterpillars burn : 

 Parch' a was the grass, and blighted was the corn." DRYDEN. 



tall trees upon which it feeds, and also to bend the neck when 

 drinking from springs, and other places where water is found ? 



517. Wliy has the dromedary a hump upon its back ? 



This hump is an accumulation of a peculiar species of fat which 

 is not liable to be acted upon by the great heat to which the animal 

 is exposed. It consists chiefly of stearine, or hard fat. It is, in 

 fact, a store of nourishment beneficently provided against the day of 

 want, to which the animal in a wild state is often exposed, and from 

 which he is not entirely exempted in a state of domestication. 

 The dromedary or camel can exist for a long period upon this 

 hump alone, without any other food ; and it does not die of want 

 until the hump has been entirely absorbed, and applied to the 

 nourishment of the system. 



518. Animals which exist chiefly upon vegetable matter, and which are subject 

 to seasonal vicissitudes in their supply of food, all make accumulations of fat on 

 some part of their bodies, as a provision against the failure of the supply of food ; 

 and their tendency to this habit is exactly in proportion to the need they have for it. 

 The parts of the body iu which this accumulation is made, and the consistency of the 

 accumulated substance, are both very important points in the geographical distribu- 

 tion of animals. If the animal winters in cold latitudes, the accumulation r ( fat is 

 generally distributed over the surface, and the substance is of a soft auJ oily 

 nature. If, on the other hand, it inhabits warm latitudes, t ie accu- 

 mulation is chiefly composed of a crystalli/able fat, and is generally suuated on 

 some part of the animal where it is least likely to interrupt its labour and progress. 



519. Why is the formation of the stomach of the camel and flu 

 dromedary admirably adapted for enabling the animal to Idb, long 

 journeys over parched deserts ? 



Because the stomachs of these animals are capable oi retaining 

 large quantities of water unchanged for a considerable length of 

 time. A number of distinct sacs are observed to lie between the 

 membranes of the second stomach, and to open into the stomach 

 near the top by small square apertures. Through these orifices, 

 after the stonr.ich is full, the annexed bags are filled : ai* 



