1728 THE PIC A RI AN BIRDS 



and the protrusion of the tongue is caused by the action of a certain muscle 

 diminishing the curve in which the extremities of the tongue bones lie when 

 the tongue itself is withdrawn. In only two American genera of the family 

 is this remarkable structure absent. The bill in all the woodpeckers is strong 

 and chisel shaped, and is thus admirably adapted for hewing holes and prizing 

 off bark to capture insects, the viscid secretion on the tongue being of great 

 use in the latter function, but in the ground-haunting species the bill is less 

 powerful. 



There is very little variation in the habits of the members of this family, 

 nearly all climbing trees, in the stems of which they bore out holes for their 

 nesting place, the direction of the aperture being at first horizontal and then 

 descending to a depth varying from a few inches to several feet. No nest is 

 formed, the eggs, which are always glossy white, or pinkish white, being 

 deposited on the chips which are accumulated by the birds during the excavation of 

 the hole. They vary from two to seven or eight in number, but the average clutch 

 is four or five. The young are hatched naked and blind, and in this state they 

 remain for some time, although they soon become vigorous, the clamor with which 

 they greet their parents, when the latter bring food to the nest, being proverbial. 

 They soon learn to climb to the mouth of the hole, and even sleep in a hanging- 

 position. The tenacity with which the claws grasp the bark of a tree is often illus- 

 trated even in death, for sometimes a woodpecker, when fatally wounded by shot, 

 automatically grips the trunk with such vigor as to remain suspended. The 

 geographical range of the woodpeckers includes the whole of America, Africa, 

 Europe, and northern and tropical continental Asia, although no species are found 

 to the eastward of Celebes, the group being entirely unrepresented in Australasia 

 and the Pacific islands. The only fossil representative of the group hitherto 

 described appears to be one from the Tertiary strata of the Uinta mountains, in the 

 United States, and hence named Uintornis; but how close this comes to existing 

 forms does not admit of determination. 



Constituting a single family, the woodpeckers may be subdivided into two 

 minor groups, namely, those with stiffened tails, and those with soft tails. As with 

 other climbing birds, such as the creepers and woodhewers, among the Passerines, 

 the stiffened tail is an accessory to ascending trees. In the present group it is the 

 shaft or stem of the feathers which is stiffened and elastic, the ends of the same 

 being generally narrowed to a point, and the webs often showing signs of wear and 

 tear, as the tail is constantly dragged along the rough bark of a tree, or is used as a 

 support for the body of the bird, when the latter hammers away at the bark to pro- 

 cure its insect food. In some instances the tail feathers assume a more remarkable 

 shape, the hardened webs being turned inward from their outer edges, so as to 

 make a kind of hollow half tube, this being particularly observable in the imperial 

 woodpecker. The tail of some of the larger kinds of woodpeckers must, in fact, 

 work havoc among the insects on the bark of a tree when the bird is climbing up, 

 and we have seen the tail of a rufous woodpecker, in which the feathers were 

 covered with the heads of ants on the under side, numbers of the insects being 

 attached to the tail feathers of the bird. 



