456 OBSERVATIONS ON 



subsist: for they withdraw themselves, and are hardly 

 ever seen, nor do any insects appear for their support. 

 That they can retire to rest, and sleep away these un- 

 comfortable periods as the 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. 



September 13, 1791. The congregating flocks of 

 Hirundines on the church and tower are very beautiful 

 and amusing ! When they fly off all 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 dfty, 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 four hundred 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 New ton vicarage-house, hovering and settling 

 on the roofs and out-buildings. None have been ob- 

 served at Selborne since October 1 1. It is very remark- 

 able, that after the Hirundines have disappeared for 

 some weeks, a few are occasionally seen again ; some- 

 times, in the first week in November, and that only for 

 one day. Do they not withdraw and slumber in some 

 hiding place during the interval? for we cannot suppose 



