CONGREGATING OF BIRDS. 169 



the motive for the proceeding, may it not arise 

 from the helplessness of their state in such rigorous 

 seasons ; as men crowd together, when under 

 great calamities, though they know not why ? 

 Perhaps approximation may dispel some degree 

 of cold ; and a crowd may make each individual 

 appear safer from the ravages of birds of prey and 

 other dangers. 



If I admire when I see how much congenerous 

 birds love to congregate, I am the more struck 

 when I see incongruous ones in such strict amity. 

 If we do not much wonder to see a flock of rooks 

 usually attended by a train of daws, yet it is 

 strange that the former should so frequently have 

 a flight of starlings for their satellites. Is it 

 because rooks have a more discerning scent than 

 their attendants, and can lead them to spots more 

 productive of food ? Anatomists say that rooks, 

 by reason of two large nerves which run down 

 between the eyes into the upper mandible, have 

 a more delicate feeling in their beaks than other 

 round-billed birds, and can grope for their meat 

 when out of sight. Perhaps, then, their associates 

 attend them on the motives of interest, as grey- 

 hounds wait on the motions of their finders, and 

 as lions are said to do on the yelping of jackals. 

 Lapwings and starlings sometimes associate. 



XII. 



As a gentleman and myself were walking on 

 the 4th of last November round the sea-banks at 

 Newhaven, near the mouth of the Lewes river, 

 in pursuit of natural knowledge, we were surprised 

 to see three house swallows gliding very swiftly 

 by us. That morning was rather chilly, with the 



