160 SAND-MARTENS. 



One thing is remarkable, that, after some years, the old 

 holes are forsaken, and new ones bored ; perhaps because the 

 old habitations grow foul and fetid from long use, or because 

 they may so abound with fleas as to become untenantable. 

 This species of swallow, moreover, is strangely annoyed with 

 fleas ; and we have seen fleas, bed-fleas, (pulex irritans, *) 

 swarming at the mouths of these holes like bees on the stools 

 of their hives. 



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-marten 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 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 libellultz, (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-martens 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-martens. 



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 congre- 

 gating with their congeners in the autumn. Undoubtedly 

 they breed a second time, like the house-marten and swallow, 

 and withdraw about Michaelmas. 



Though, in some particular districts, they may happen to 



* Our author is wrong in supposing these insects to be the common. 

 *>ed-flea ; it is the swallow-flea, (pulex hirundinis of Stephens,) by which 

 they are infested. ED. 



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