chap, x Instinct 161 



of an z. To seize between the points of the mandibles at 

 the very instant of striking, seemed a more difficult opera- 

 tion. I have seen a chicken seize and swallow an insect at 

 the first attempt ; most frequently, however, they struck 

 five or six times, lifting once or twice before they succeeded 

 in swallowing their first food." Again, " The art of scrap- 

 ing in search of food, which, if anything, might be acquired 

 by imitation, for a hen with chickens spends the half of her 

 time in scratching for them, is nevertheless another indis- 

 putable case of instinct. Without any opportunities of 

 imitation, when kept quite isolated from their kind, chickens 

 began to scrape when from two to six days old. Generally 

 the condition of the ground was suggestive ; but I have 

 several times seen the first attempt, which consists of a sort 

 of nervous dance, made on a smooth table." Another 

 experimenter " hatched out some chickens on a carpet, 

 where he kept them for several days. They showed no 

 inclination to scrape, because the stimulus supplied by the 

 carpet to the soles of their feet was of too novel a character 

 to call into action the hereditary instinct ; but when a little 

 gravel was sprinkled on the carpet, and so the appropriate 

 or customary stimulus supplied, the chickens immediately 

 began their scraping movements." 



Another instance of the first class of instincts is the fear 

 said to be shown by many animals for their natural foes ; 

 but on this point we find a certain conflict of evidence. 

 Thus kittens are said to show disgust at a dog, and, while 

 still blind, at a hand that has touched and smells of a dog, or 

 to tremble with excitement at the smell of a mouse. A chicken 

 or young turkey will show evident signs of fear at hearing 

 the cry of a hawk. Ants of various species that are mutually 

 hostile recognise an enemy, and fight ; but, on the other 

 hand, there are observations to the effect that, if taken young 

 enough, ants of several such species may be brought up 

 together as a happy' family. 



The instinctive tameness or wildness of many animals 

 towards man is probably the effect of intelligence and infor- 

 mation given to one another ; as is the avoidance of the 

 same kind of trap, after a short experience of its properties, by 



M 



