78 INSTINCTS. 



lety for the general preservation of the species ; a kind of 

 patriotism ; a solicitude, lest the butterfly race should cease 

 from the creation. 



Lastly, the principle of association will not explain the 

 discontinuance of the affection when the young animal 

 is grown up. Association, operating in its usual way, 

 would rather produce a contrary effect. The object would 

 become more necessary by habits of society ; whereas 

 birds and beasts, after a certain time, banish their off- 

 spring ; disown their acquaintance ; seem to have even no 

 knowledge of the objects which so lately engrossed the 

 attention of their minds, and occupied the industry and 

 labour of their bodies. This change, in different animals, 

 takes place at different distances of time from their birth ; 

 but the time always corresponds with the ability of the 

 young animal to maintain itself ; never anticipates it. In 

 the sparrow tribe, when it is perceived that the young 

 brood can fly and shift for themselves, then the parents 

 forsake them forever ; and though they continue to live 

 together, pay them no more attention than they do to other 

 birds in the same flock, * I believe the same thing is true 

 of all gregarious quadrupeds. 



In this part of the case the variety of resources, expedi- 

 ents, and materials, which animals of the same species are 

 said to have recourse to, under different circumstances and 

 when differently supplied, makes nothing against the doc- 

 trine of instincts. The thing which we want to account 

 for is the propensity. The propensity being there, it is 

 probable enough that it may put the animal upon different 

 actions according to different exigencies. And this adapt- 

 ation of resources may look like the effect of art and con- 

 sideration, rather than of instinct; but still the propensity is 

 instinctive. For instance, suppose what is related of the 

 wood-pecker to be true, that, in Europe, she deposits '^her 

 eggs in cavities, which she scoops out in the trunks of soft 

 or decayed trees, and in which cavities the eggs lie con- 

 cealed from the eye, and in some sort safe from the hand 

 of man ; but that, in the forests of Guinea and the Brazils, 

 which man seldom frequents, the same bird hangs her 

 nest to the twigs of tall trees ; thereby placing them out of 

 the reach of monkeys and snakes, i. e. that in each situa- 

 tion she prepares against the danger which she has most 

 occasion to apprehend ; suppose, I say, this to be true, and 



* Goldsmith's Nat. Hist. vol. iv. p. 244. 



