50 Habit and Instinct. 



differences are emphasized through experience. A large 

 fly with clipped wings was thrown among some two-days- 

 old chicks. Only one dared approach it, and he gave the 

 danger note. Presently, however, he followed and caught 

 it, after several failures. Shortly afterwards another was 

 given them; the one who had learnt by experience that 

 the fly was harmless and nice to eat ran and caught it at 

 the second shot. "While small worms are picked up with 

 avidity, large worms are left alone by quite young birds, 

 and often evoke the alarm note. None of the chicks on 

 their fifth day dared go near a particularly large worm. 

 Bits of red-brown worsted, somewhat resembling worms, 

 were seized with eagerness and eaten with surprising 

 avidity, so long as they were not more than a couple 

 of inches long. Of a four-inch bit the chicks were afraid, 

 until one, bolder than the rest, seized it, whereupon 

 the others chased him for the prize till he escaped to a 

 secluded corner and swallowed it. On their eighth day the 

 chicks stood timidly round a lump of sugar I had thrown in 

 among them, uttering the danger note, and then ran at it, 

 pecking rapidly and withdrawing in haste. Young moor- 

 hens were at first shy of large worms, but soon ate the 

 biggest I could find. A little pheasant which would run to 

 my hand for wasp larvse placed upon the palm, one 

 morning gave the alarm note, and would not as usual jump 

 upon my fingers. Four or five of the grubs had stuck 

 together so as to form a large mass of which he was afraid! 

 Moorhen chicks were at first afraid of the common yellow 

 underwing moth and of the gammaimoth, though both were 

 eaten freely after I had given them dead moths. 



No doubt the response to the sight of a moving 

 object may look at first blush like instinctive recogni- 

 tion. Plovers seized small worms with an avidity which 

 looked like an inherited recognition of natural food, but of 



