588 BANK SWALLOW. 
them, but frequently snatch them from the tops of grasses or other 
plants on which they have alighted. They also seize small aquatic 
insects ; but, although I suspect that they disgorge in pellets the 
harder parts of these, I have no proof, obtained from actual observa- 
tion, that they do so. 
The holes perforated by this species for the purpose of breeding 
require considerable exertion and labour. They are usually bored at 
the distance of two or three feet from the summit of the bank or sur- 
face of the ground, to the depth of about three feet, but sometimes to 
that of four or even five. They are near each other or remote, accord- 
ing to the number of pairs of swallows that resort to the place, and 
the extent of the bank. In one situation you may find not more than 
a dozen pairs at work, while in another several hundreds of holes may 
be seen scattered over some hundreds of yards. On the bluffs of the 
Ohio and the Mississippi there are many very extensive breeding- 
places. While engaged in digging a sand-bank on the shore of the 
Ohio, at Henderson, for the purpose of erecting a steam-mill, I was 
both amused and vexed by the pertinacity with which the little winged 
labourers continued to bore holes day after day, whilst the pickaxes 
and shovels demolished them in succession. The birds seemed to have 
formed a strong attachment to the place, perhaps on account of the fine 
texture of the soil, as I observed many who had begun holes a few . 
hundred yards off abandon them, and join those engaged in the newly 
opened excavation. Whether the holes are frequently bored horizon- 
tally or not I cannot say, but many which | examined differed in this 
respect from those described by authors, for on introducing a gun-rod 
or other straight stick, I found them to have an inclination of about 
ten degrees upwards. The end of the hole is enlarged in the form of 
an oven, for the reception of the nest, and the accommodation of the 
parents and their brood. 
_ When the birds have for a while examined the nature of the bank, 
they begin their work by alighting against it, securing themselves by the 
claws, and spreading their tails considerably so as, by being pressed 
against the surface, to support the body. The bill is now employed in 
picking the soil, until a space large enough to admit the body of the 
bird is formed, when the feet and claws are also used in scratching out 
the sand. I have thought that the slight ascent of the burrow contri- 
buted considerably to enable the bird to perform the severe task of dis- 
ee ee 
u 
