OF SELBORNE 149 



through that month, and some occasionally to the beginning of 

 November. This early retreat is mysterious and wonderful, since 

 that time is often the sweetest season in the year. But, what is 

 more extraordinary, they begin to retire still earlier in the most 

 southerly parts oi Andalusia, where they can be no ways influenced 

 by any defect of heat ; or, as one might suppose, defect of food.i 

 Are they regulated in their motions with us by a failure of food, 

 or by a propensity to moulting, or by a disposition to rest after 

 so rapid a life, or by what ? This is one of those incidents in 

 natural history that not only baffles our searches, but almost 

 eludes our guesses ! 



These hirundines never perch on trees or roofs, and so never 

 congregate with their congeners. They are fearless while haunt- 

 ing their nesting places, and are not to be scared with a gun ; 

 and are often beaten down with poles and cudgels as they stoop 

 to go under the eaves. Swifts are much infested with those pests 

 to the genus called hippohoscw hirundinis ; and often wriggle and 

 scratch themselves, in their flight, to get rid of that clinging 

 annoyance. 



Swifts are no songsters, and have only one harsh screaming 

 note ; yet there are ears to which it is not displeasing, from an 

 agreeable association of ideas, since that note never occurs but in 

 the most lovely summer weather. 



They never settle on the ground but through accident ; and 

 when down can hardly rise, on account of the shortness of their 

 legs and the length of their wings : neither can they walk, but 

 only crawl ; but they have a strong grasp with their feet, by 

 which they cling to walls. Their bodies being flat they can 

 enter a very narrow crevice ; and where they cannot pass on 

 their bellies they will turn up edgewise. 



The particular formation of the foot discriminates the swift 

 from all the British hirundines ; and indeed from all other known 

 birds, the hirundo melba, or great white-bellied swift of Gibraltar, 

 excepted ; for it is so disposed as to carry " omnes quatuor digitos 

 anticos " all it's four toes forward ; besides the least toe, which 

 should be the back-toe, consists of one bone alone, and the other 

 three only of two apiece. A construction most rare and peculiar, 

 but nicely adapted to the purposes in which their feet are em- 



1 [This observation of John White, chaplain at Gibraltar, is hardly confirmed 

 by Col. Irby, who says that the majority of the swifts leave by the end of August, 

 some staying on till the middle of September (Ornithology of the Straits of Gibraltar, 



p. 122).] 



