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their nest in porches, gateways, and galleries. Gilbert
White mentions one that built for two years together in the
handles of a pair of shears, which were reared against an
outhouse; and another that made its nest on the wings and
body of a dead owl.

The House Martin (H. urbica) has the whole of the upper
part of the body black, with the exception of a patch of white
above the tail, while the under part is of a pure white,
slightly tinged with grey in the female. It builds its nest
under a projecting roof if possible; and when unable to do
this, constructs a dome to keep off the rain. Jesse mentions
a martin which built its nest, and reared its brood, on the
knocker of the hall-door at a gentleman’s house in Warwick-
shire. When the door was opened, the bird quitted its nest
for a short time, but returned when the door was closed.
In some parts of the country the house martin rears three
broods in the year, laying four or five eggs each time. In
the intervals the house sparrow sometimes takes possession
of the nest, and the former owner is said to build her in,
as she cannot forcibly eject the intruder. The eggs are
white, inclining to dusky at the thicker end. The martin
generally migrates in October.

The Sand Martin (H. riparia) is the smallest of the

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