of 



the first summer to mqt the increasing weight of 

 the growing body. 



Where there are peculiar uses made of the tail, as 

 with the chimney swifts and woodpeckers, there is a 

 peculiar order of moulting. In most birds the tail is 

 a kind of balance or steering-gear, and not of equal 

 importance with the wings. Nature, consequently, 

 seems to have attached less importance to the feath- 

 ers of the tail. They are not so firmly set, and they 

 are hardly of the same quality or kind; for if a wing 

 feather is once broken or lost, after the moult, it must 

 go unmended until the annual moulting time comes 

 round again ; whereas, if a tail feather is lost through 

 accident, it is made good, no matter when. How 

 do you explain that? I know that old theory of the 

 birds roosting with their tails out, and so, through 

 generations of lost tails, those feathers now grow, 

 expecting to be plucked by some enemy, and so have 

 only a temporary hold. Perhaps. 



The normal, natural way, of course, is to replace a 

 lost feather with a new one as soon as possible ; but 

 in order to give .extra strength to the wing feathers 

 nature has found it necessary to check their frequent 

 change, and so complete is the check that the annual 



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