for their support. That they can retire to rest, and sleep away these uncomfortable periods, as bats do, is a matter rather to be suspected than proved; or do they not rather spend their time in deep and sheltered vales near waters, where insects are more likely to be found? Certain it is, that hardly any individuals of this genus have at such times been seen for several days together.
Sept. 13th, 1791. The congregating flocks of hirundines on the church and tower are very beautiful and amusing! When they fly off together from the roof, on any alarm, they quite swarm in the air. But they soon settle in heaps, and preening their feathers, and lifting up their wings to admit the sun, seem highly to enjoy the warm situation. Thus they spend the heat of the day, preparing for their emigration, and, as it were, consulting when and where they are to go. The flight about the church seems to consist chiefly of house-martins, about 400 in number; but there are other places of rendezvous about the village frequented at the same time.
It is remarkable that though most of them sit on the battlements and roof, yet many hang or cling for some time by their claws against the surface of the walls, in a manner not practised by them at any other time of their remaining with us.
The swallows seem to delight more in holding their assemblies on trees.
November 3rd, 1789. Two swallows were seen this morning at Newton vicarage-house, hovering and settling on the roofs and out-buildings. None have been observed at Selborne since October 11th. It is very remarkable, that after the hirundines have disappeared for some weeks, a few are occasionally seen again; sometimes, in the first week in November, and that only for one day. Do they not withdraw and slumber in some hiding-place in the interval? For we cannot suppose they had emigrated to warmer climes and so returned again for one day. Is it not more probable that they are awakened from sleep, and like the bats, are come forth to collect a little food? Bats appear at all seasons through the autumn and spring months, when the thermometer is at 50°, because then phalænæ and moths are stirring.
These swallows looked like young ones.—White.
