THE WOODPECKER'S TOOLS: HIS TAIL 89 



one third the length of his whole body measured 

 from the tip of the bill to the tip of the tail. 

 Probably this is the proportion most convenient 

 for his work. 



All woodpeckers' tails agree in one particular : 

 they are rounded at the end. At first sight we 

 would say that some are but slightly rounded 

 and others very deeply graduated ; but as nearly 

 as I can determine this is at least partly an optical 

 illusion, explained by the great difference in the 

 shape of the feathers making up the tail, which 

 in some, as the flicker, are very broad and ab- 

 ruptly pointed, and in others taper gradually to 



Middle tail feathers of Flicker, Ivory-billed Woodpecker, and 

 Hairy Woodpecker. 



the end and are very narrow for their length. 

 The larger birds naturally appear to have longer 

 tails, and the effect of narrow feathers is to 

 make the tails appear longer and more sharply 

 graduated than they really are. This diagram 



