THE TAIL 31 



The principal union of toes is through their connection by a 

 thin, movable membrane; this, whether small or large, is 

 called webbing. In many families of birds, the three front toes 

 have a distinct webbing at base only ; if this webbing does not 

 reach more than half way, the feet are semipalmate.'^ In the 

 ducks, terns, etc., the front toes are webbed to the claws. This 

 plan, which is so common, is called palmate}'^ A few of our 

 birds have all four toes joined by a full webbing, and for this 

 arrangement the word totipalmate " is used. Some birds with 

 more or less webbing at the base of the toes have, in addition, 

 a stiff, spreading membrane along the sides, sometimes lobed, 

 sometimes plain ; this plan is called lobate}^ In the sea ducks, 

 the front toes are palmate and the hind toes lobate ; ^^ in the 

 grebes, the front toes are lobate. Many of the snipes have a 

 narrow border along the edges of the toes, but not wide enough 

 to be called lobate ; these are said to be margined}'^ 



CHAPTER VI 

 THE TAIL 



Use. — The general office of the tail is to guide the bird in 

 flight, but it is also used for other purposes. The wood- 

 pecker climbs trees, and the chimney swift climbs and rests 

 on the sides of chimneys by its aid. 



Kinds of feathers. — The feathers of the tail, like those of 

 the wings, are of two sorts : quilUih? feathers and coverts. The 

 true tail feathers, or rectrices, are stiff, pennaceous, well-devel- 

 oped feathers having a strong quill and a broad, spreading vane, 

 with rarely any plain aftershaft, or downy portion. The 

 inner side of the vane is wider than the outer. The number 



