LIX.] OF SELBORNE 
One thing is remarkable— that, after some years, the ohl holes 
are forsaken and new ones bored ; perhaps because the old habi- 
tations 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 
liave seen fleas, bed-fleas {Pidex iTvitans), 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-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 nidifi- 
cation, 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 some- 
times they are fed with lihdlidm (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 ])ercliers ; 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 inclosures, they 
are frequently dispossessed of tlieir 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 ajiproaches 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-martin and swallow, and 
withdraw about Michaelmas. 
