HIRUNDO EUSTICA. 85 



setting in, the true migratory birds begin to appear." It is too long 

 a passage to quote. These monsoons seem to be something hke our 

 equinoctial gales. 



Those who hold the opinion that birds migrate by instinct should read 

 the convincing chapter on the way Indians travel through unknown forests 

 (Wallace's ^Natural Selection/ p. 206 et seqq,^, which proves that man 

 does not possess instinct, neither can any one find his way in an unknown 

 forest. I contend, then, that what man with intelligence is unable to do, 

 birds must fail to accomplish. But birds do migrate with success when 

 fresh from the nest (as the Nightingale and the young Cuckoo, the one 

 before its parents, the other after them), and without aid from experience. 

 No doubt ; but they are carried in the way I have indicated (not quite 

 blindly, but nearly so), like the seeds. The only alternative is a sort of 

 miraculous and unknown instinct, unique in Nature, and a factor of an 

 incredible kind. 



But a ship does not sail always with the wind ; neither does the bird. 

 The ship is ruled by the wind; so is the bird. The bird is a sailing ship. 

 Its tail is the rudder, and it is governed by the wind ; and this is how it finds 

 its way, just as the seeds find their way. 



Urged by migratory impulse (a corporeal force), the bird starts. After 

 it has set forth it is ruled, for the most part, by circumstances, of which 

 wind is the chief. I am the more convinced of this from the following 

 consideration. For perhaps forty years I have put down and made notes of 

 the dates of the capture of birds more or less rare ; and what has struck me 

 as astonishing (the result of so much labour) was the fact that when a very 

 scarce bird was taken at a particular place, on that very spot next year, at 

 the same date, or nearly, you might with high probability expect to find 



VOL. II. N 



