OBSERVATIONS ON BIRDS. 283 



before ; from whence, then, could these few birds come, if not from 

 some hole or cavern where they had laid themselves up for the winter 1 

 Surely it will not be asserted that these birds migrate back again from 

 some distant tropical region, merely on the appearance of a fine day or 

 two at this late season of the year. Again, very early in the spring, 

 and sometimes immediately after very cold severe weather, on its 

 growing a little warmer, a few of these birds suddenly make their 

 appearance, long before the generality of them are seen. These 

 appearances certainly favour the opinion of their passing the winter in 

 a torpid state, but do not absolutely prove the fact ; for who ever saw 

 them reviving of their own accord from their torpid state, without 

 being first brought to the fire, and as it were, forced into life again ; 

 soon after which revivification they constantly die. MARKWICK. 



SWALLOWS, CONGREGATING AND DISAPPEARANCE OF. 



During the severe winds that often prevail late in the spring, it is 

 not easy to say how the hirundines subsist ; for they withdraw them- 

 selves, and are hardly ever seen, nor do any insects appear for their 

 support. That they can retire to rest, and sleep away these uncom- 

 fortable 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 1 Certain 

 it is, that hardly any individuals of this genus have at such times been 

 seen for several days together. 



September 13, 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 3, 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 11. 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 



