106 THE BOOK OF THE OPEN AIR 



nized perching place only four feet only the ledge was a little further off- 

 down a cliff, I leant cautiously over I dropped several small pieces of 

 and for ten engrossing minutes watched chalk on to a tiercel's J broad back 

 a magnificent female peregrine before before he perceived the gravity (to 

 she looked up ; and at another time him) of the situation. 



XXII 

 SUMMER VISITORS 



"Come, come is the swallow, 

 Bringing hours of fair weather, 

 Fair seasons to follow. 

 He is white on his belly, 

 But his back, it is black." 



Translated from the Greek by R. C. TREVELYAN. 



OOME authorities dignify a bird being the favoured resorts. Although 

 with the name of " British " this annual migration is one of the 

 on the single summary ground that puzzles of natural history, especially as 

 a specimen has been authenticated regards the evident system with which 

 a synonym for " shot " in the island, it is yearly carried out, a few of its 

 On this classification we can boast main principles are now well under- 

 about 400 species. On the more ex- stood, and it remains only for some 

 acting qualification that a bird must causative genius to discover the mean- 

 have attempted to rear a family here ing of the instinct which underlies it. 

 in a state of nature, we can claim about The following deductions from obser- 

 200 species ; and on the only convinc- vation show that in its working it is 

 ing classification, that which requires far more inexorable than the law of 

 an annual visit, our avi-fauna is still fashion which governs the annual 

 further reduced to about 180, of exodus from London, 

 which 36 are summer visitors, arriving It is totally independent of both wind 

 here in the spring to breed, and de- and weather in the country to which 

 parting before summer is well over to it is migrating. We have no sufficient 

 winter in some sunnier clime, Africa, observations to lay down laws as to 

 India, China, and parts of Asia Minor the weather factor in the countries 



1 Tiercel is a term used for the male peregrine ; the female, to distinguish her, is called 

 the falcon. J. W. B. 



