132 
THE NATURAL HISTORY 
[LETT. 
Now as to the business of food : as these animals are actuated 
by instinct to liunt for necessary food, they should not, one 
would suppose, crowd together in pursuit of sustenance at a 
time when it is most likely to fail ; yet such associations do 
take place in hard weather chiefly, and thicken as the severity 
increases. As some kind of self-interest and self-defence is no 
doubt the motive for tlie proceeding, may it not arise from the 
helplessness of their state in such rigorous seasons ? just 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 p>rey and other dangers. 
If I admire when I see how much congenerous birds love to 
congregate, I am the more struck when I see incongenerous 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 motive of interest, as greyhounds wait on the motions 
of their finders ; and as lions are said to do on the yelpings of 
jackals. Lapwings and starlings sometimes associate. 
Selborne, Feb. 8, 1772. 
