266 BIRD WATCHING 



signal, and that these are followed by those nearest 

 to them, and so on till the whole are in motion, then 

 two other difficulties arise, neither of which seems 

 easy to get over. For, in the first place, the birds do 

 not, in many cases, appear to rise in this manner, 

 but, as in the instances here given, simultaneously, 

 or, at least, with a nearer approach to it than any 

 process of spreading, such as here supposed, would 

 seem to admit of; and secondly, it is difficult to 

 understand how, if this were the case, any bird or, 

 at least, any few birds could fly up without putting 

 all the others in motion. Yet, as I have mentioned, 

 birds in twos or threes, or in small parties, were con- 

 stantly rising and flying from one place to another 

 in the assemblage of which they formed a part, whilst 

 the vast majority remained where they were, on the 

 ground. This fact offers an equal or a still greater 

 difficulty, if, dismissing the idea of there being a 

 recognised leader, we suppose that any bird may, for 

 the moment, become one by taking the initiative 

 of flight, or otherwise. And even if we assume that 

 any of these explanations is the correct one, in the 

 case of a whole body of rooks taking sudden flight, 

 or directing their flight to any particular place, or 

 with any special purpose, what are we to think when 

 half, or a certain number of the band does one thing, 

 and the other half another, each, apparently, with 

 equal spontaneity? We are met here with the same 

 difficulties and perhaps in a still higher degree as 

 in the case of the flocks of small birds at the stacks 

 in winter. 



"If rooks follow and obey a leader, one might 

 expect them to do so habitually, at least in their 



