84 PHILOSOPHY OF ZOOLOGY. 



active little animal prepares its winter-habitation among the 

 large branches of an old tree. After making choice of the 

 place where the timber is beginning to decay, and where 

 a hollow may be easily formed, it scoops out with its teeth 

 a suitable magazine. Into this storehouse, acorns, nuts, 

 and other fruits, are industriously conveyed, and carefully 

 concealed. This granary is held sacred until- the incle- 

 mency of the weather has limited the range of its excur- 

 sions, and consequently diminished its opportunities of pro- 

 curing food. It then begins to enjoy the fruits of its in- 

 dustry, and to live contentedly in its elevated dwelling. 



III. SITUATION. 



Animals are restricted by instinctive feelings, to particu- 

 lar situations. An attentive examination of all the physical 

 conditions of the situation preferred by each species, and 

 a comparison of these with the arrangement of the organs, 

 will enable us, in many cases, to perceive the propriety, or 

 rather, the necessity of the choice. The animals which 

 reside in water, are possessed of organs of motion and re- 

 spiration, which can execute their functions only in that 

 element, in which also their most suitable food is to be ob- 

 tained. In some cases, these organs are suited to a resi- 

 dence in salt water, in others, in fresh water, still farther in- 

 fluenced by the temperature and motions which these expe- 

 rience. Again, in the animals which reside on land, we 

 observe the organs of locomotion, respiration, and percep- 

 tion, fitted only for a residence in such a situation. A va- 

 riety of other circumstances likewise exercise a powerful 

 influence, as temperature, shelter, and moisture. 



All aquatic animals, of the vertebral division, which 

 breed and sleep in the water, are restricted to a constant 

 residence in that element, and consequently can exist only 

 in those regions where it occurs. The whale, indeed, could 



