NATURAL HISTORY OF SELBORNE. 129 



The following circumstance should by no means be omitted that 

 these birds do not make use of their caverns by way of hybernacula, as 

 might be expected ; since banks so perforated have been dug out with 

 care in the winter, when nothing was found but empty nests. 



The sand-martin arrives much about the same time with the 

 swallow, and lays, as she does, from four to six white eggs. But as 

 this species is cryptogame, carrying on the business of nidification, 

 incubation, and the support of its young in the dark, it would not be 

 so easy to ascertain the time of breeding, were it not for the coming 

 forth of the broods, which appear much about the time, or rather 

 somewhat earlier than those of the swallow. The nestlings are supported 

 in common like those of their congeners, with gnats and other small 

 insects ; and sometimes they are fed with libellulce (dragon-flies) almost 

 as long as themselves. In the last week in June we have seen a row of 

 these sitting on a rail near a great pool as perchers, and so young and 

 helpless, as easily to be taken by hand ; but whether the dams ever 

 feed them on the wing, as swallows and house-martins do, we have 

 never yet been able to determine ; nor do we know whether they 

 pursue and attack birds of prey. 



When they happen to breed near hedges and enclosures, they are 

 dispossessed of their breeding holes by the house-sparrow, which is on 

 the same account a fell adversary to house-martins. 



These hirundines are no songsters, but rather mute, making only a 

 little harsh noise when a person approaches their nests. They seem not 

 to be of a sociable turn, never with us congregating with their congeners 

 in the autumn. Undoubtedly they breed a second time, like the house- 

 martin and swallow ; and withdraw about Michaelmas. 



Though in some particular districts they may happen to abound, 

 yet in the whole, in the south of England at least, is this much the 

 rarest species. For there are few towns or large villages but what 

 abound with house-martins ; few churches, towers, or steeples, but what 

 are haunted by some swifts ; scarce a hamlet or single cottage-chimney 

 that has not its swallow ; while the bank-martins, scattered here and 

 there, live a sequestered life among some abrupt sand-hills, and in the 

 banks of some few rivers. 



These birds have a peculiar manner of flying ; flitting about with 

 odd jerks, and vacillations, not unlike the motions of a butterfly. 

 Doubtless the flight of all hirundines is influenced by, and adapted to, 

 the peculiar sort of insects which furnish their food. Hence it would 

 be worth inquiry to examine what particular genus of insects affords 

 the principal food of each respective species of swallow. 



Notwithstanding what has been advanced above, some few sand- 

 martins, I see, haunt the skirts of London, frequenting the dirty pools 

 in Saint George's Fields, and about Whitechapel. The question is 

 where these build, since there are no banks or bold shores in that 

 neighbourhood ; perhaps they nestle in the scaffold holes of some old 

 or new deserted building. They dip and wash as they fly sometimes, 

 like the house-martin and swallow. 



Sand-martins differ from their congeners in the diminutiveness of 

 their size, and in Iheir colour, which is what is usually called a mouse- 



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