THE DARWINIAN THEORY OF INSTINCT. 589 



from time to time fresh food to her young, and remembers very ex- 

 actly the entrance to her cell, although she has covered it with sand, 

 so as not to be distinguishable from the surrounding surface. Yet M. 

 Fabre found that if he brushed away the earth and the underground 

 passage leading to the nursery, thus exposing the contained larva, the 

 parent insect " was quite at a loss, and did not even recognize her own 

 offspring. It seemed as if she knew the doors, nursery, and the pas- 

 sage, but not her child." 



Lastly, instinct is always similarly manifested under similar circum- 

 stances by all the individuals of the same species. And, it may be 

 added, these circumstances are always such as have been of frequent 

 occurrence in the life-history of the species. 



Now, in all these respects instinct differs conspicuously from every 

 other faculty of mind, and especially from reason. Therefore, to gather 

 up all these differentice into one definition, we may say that instinct is 

 the name given to those faculties of mind which are concerned in con- 

 sciously adaptive action, prior to individual experience, without neces- 

 sary knowledge of the relation between means employed and ends 

 attained ; but similarly performed under similar and frequently recur- 

 rinof circumstances by all the individuals of the same species. 



Such being my definition of instinct, I shall now pass on to con- 

 sider Mr. Darwin's theory of the origin and development of instincts. 



Now, to begin with, Mr. Darwin's theory does not, as many sup- 

 pose that it does, ascribe the origin and development of all instincts 

 to natural selection. This theory does, indeed, suppose that natural 

 selection is an important factor in the process ; but it neither supposes 

 that it is the only factor, nor even that in the case of numberless in- 

 stincts it has had anything at all to do with their formation. Take, 

 for example, the instinct of wildness, or of hereditary fear as directed 

 toward any particular enemy — say man. It has been the experience 

 of travelers who have first visited oceanic islands without human in- 

 habitants, and previously unvisited by man, that the animals are desti- 

 tute of any fear of man. Under such circumstances the birds have 

 been known to alight on the heads and shoulders of the new-comers, 

 and wolves to come and eat meat held in one hand while a knife was 

 held ready to slay them with the other. But this primitive fearless- 

 ness of man gradually passes into an hereditary instinct of wildness, 

 as the special experiences of man's proclivities accumulate; and, as this 

 instinct is of too rapid a growth to admit of our attributing it to nat- 

 ural selection (not one per cent of the animals having been destroyed 

 before the instinct is developed), we can only attribute its growth to 

 the effects of inherited observation. In other words, just as, in the 

 lifetime of the individual, adjustive actions which were originally in- 

 telligent may by frequent repetition become automatic, so in the life- 

 time of the species, actions originally intelligent may, by frequent 

 repetition and heredity, so write their effects on the nervous system 



