REVIEW— ILLUSTRATIONS OF INSTINCT. 
689 
supposition is incorrect, since it is known that, in a more advanced 
period of the season, when this particular instinctive propensity is 
declining, the pair will return to the forsaken nest, and employ it 
as originally intended.” 
“ An animal feels the want of food through an instinctive im- 
pression principally arising from the state of the stomach ; and the 
complicated sensation thence arising, a mixture of the impression 
of pleasure and pain, impels it to exertion for obtaining a supply, 
of which the nature and taste are ascertained with little inquiry. 
But there are other sensations of the stomach still more painful, 
and for which there is a relief in nature, but towards which there 
appears to be no propulsive tendency : so widely different is the 
instinct arising from a natural want and a morbid action. Nor is 
there any exception to this among wild animals, as has been sup- 
posed, where the feeling arises from a derangement of any organ 
besides the stomach. A sick animal will, it is true, find out a 
plant that is not its usual food, and devour it ; but this occurs only 
when the disorder is confined to the stomach. There is no in- 
stinctive craving in derangements of other organs ; and, in its 
nature, this of the organ of digestion can only be compared to that 
similar feeling in man, which leads him to drink freely in a fever, 
or to accommodate a weak or irregular stomach b} r fanciful craving 
for food.” 
“ The organs of taste and smell, from causes hitherto unknown, 
are gratified with different odours and impressions in different crea- 
tures; and therefore we need not feel surprised if, in beings so 
differently organized, the objects sought after to satisfy the craving 
of hunger should greatly differ. And as, among men, one indi- 
vidual prefers the salt and another the sour, so we may observe in 
one pasture the sheep nibbling the short grass, the cow preferring 
the long and coarse, the horse searching out the fine and tender, 
and the ass passing the whole of these by, to shew its preference 
for the sprouts of furze. It is from a similar variation of taste 
that the tiger seeks for blood, and the bear for roots and honey, — 
the fox for birds, the weasel for eggs ; until, at last, we find that 
there is not a substance in the animal or vegetable world that is 
not the selected food of some creature, — a source of supply and 
happiness to some sentient being. And even the most filthy and 
loathsome things are a delectable treat to some of the creeping 
families, which, by devouring the putrid matter, play their part in 
purifying creation from what would annoy others, and, perhaps, 
generate disease and death.” 
“ It is by an instinct common to all wild animals that the hare 
and rabbit, the cat, fox, rat, and mole, endeavour to escape from 
their enemies; but it is a modification of this action arising from 
VOL. XX. 4 Y 
