1 84 THE WONDER OF LIFE 



Even if we postulate that they know how to make a 

 journey that they have made before, and that young birds 

 serve some apprenticeship, there rises the further ques- 

 tion, Why do they launch forth at all ? The departure 

 from Alaska in autumn is obviously intelligible, they must 

 flit or starve ; but why do they leave Hawaii ? There is 

 plenty, of room and plenty of food, and some American 

 birds a stilt, a night heron, a gallinule, a goose, a short- 

 eared owl, and a buzzard which probably came as waifs, 

 like the Golden Plover, have become resident Hawaiian 

 birds. Why does not the Golden Plover become a resident ? 

 The probable answer is a purely biological one, that, as Mr. 

 Henshaw suggests, the Golden Plovers were originally 

 Arctic birds, and that they have a homing impulse, a 

 constitutional desire to return to their cradle- country, the 

 Northern paradise from which the ice once expelled them. 

 We agree with this observer in adopting the hypothesis of 

 an organic home-sickness which prompts a return at the 

 breeding season to the original headquarters or somewhere 

 in that direction. 



Retrospect. A few examples may be as effective as 

 many thousands to illustrate that quality of living creatures 

 which every one in some instance or other has had occasion 

 to admire. When we watch the literal legions of starlings 

 circling over their resting-place on Cramond Island in the 

 Firth of Forth, or the living cataract of guillemots, razor- 

 bills, and puffins that descends from one of the great bird- 

 bergs of the North when we rattle the oars in the boat, or 

 a swarm of locusts in South Africa darkening the sky with 

 a thick curtain of wings, we feel the insurgence of life. 

 When we watch the flying-fishes rise in hundreds before the 

 prow of the steamer, like grasshoppers in a meadow ; or 



