142 BIRDS OF THE COUNTRYSIDE 



birds find their way by the exercise of intelligence, acting 

 upon instinct alone, but that the wonderful sense of 

 direction, germinally implanted as an instinct, depends 

 for its effective practice upon the qualities of the birds 

 themselves. The impulse to spring migration, for in- 

 stance, has been suggestively called a " constitutional 

 home-sickness," and the species which feel it most 

 acutely and employ all their wits and energies to making 

 a success of it will be those that survive and prosper. 

 The fact that some species puffins for example- 

 depart and arrive with a punctuality that seems 

 automatic does not affect the argument. For on the 

 one hand they have achieved this punctuality by an 

 experimentalism extending over thousands of years in 

 the past, and sea-birds are much hardier and more 

 independent of weather conditions on the other. And, 

 even though migration works almost like clockwork 

 nowadays, there are still mistakes, confusions and 

 failures remediable by learning the consequences. 

 Migration, again, is a method of " peace by negotiation," 

 a way out of the intensified struggle for subsistence 

 brought .about by over-population. 



The " survival of the fittest " means no more nor 

 less than the urge and pressure of God knocking sense 

 into hippopotami, men, water-lilies, blue-tits, spiders 

 and roses. Learn the sense to do this and avoid that, 

 and you shall live ; refuse to learn, and take the con- 

 sequences. 



Along the beach (which is all shingle and sorry 

 walking) I met with a new and uncommon species 

 here the greater black-backed gull a fine sight as 

 he flew close down by the sea, which was dead calm. 

 On the cliffs to the south of the village I watched half 

 a dozen kestrels. They would launch themselves 

 straight out from the edge of the cliff, turn abruptly 

 back, and then wheel sporting to and fro, up and down 

 the cliff-face. Their light reddish-brown matched the 

 coloration of the cliff so perfectly that when hard 

 against it they would magically disappear and as 

 suddenly re-emerge against the sky or a darker portion 

 of the cliff. Probably a young brood, exercising with 



