326 OBSERVATIONS ON BIE.DS. 



SWALLOWS, CONGKEGATING AND DISAPPEABANCE OF.* 

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

 it is not easy to say how the kirundines 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 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. 



September 13, 1791. The congregating flocks of Tiirun- 

 dines 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 emigra- 

 tion, 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 bat- 

 tlements 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. f 



November 3, 1789. Two shallows were seen this morning 

 at Newton Vicarage House, hovering and settling on the 

 roofs and out-buildings. None have been observed at Sel- 

 borne since October 11. It is very remarkable, that after 



* A correspondent informs me that he has observed that when a large 

 number of swallows have congregated in the neighbourhood of Liverpool, they 

 have suddenly disappeared, but, upon a strong gale of wind arising, they have 

 as suddenly reassembled till the gale was over. ED. 



f On the 2nd and 3rd of December, 1842, several swallows were seen 

 flying about some of the towers of Windsor Castle ; the thermometer then was 

 48, and the wind S.S.W ED. 



