80NGLESS BIRDS OF ORCHARD AND WOODLAND. 245 



them filled with insects about three times out of four. Dr. 

 Warren records the examination of sixty-two Humminw- 

 bird stomachs. The food contents were mainly small spiders, 

 beetles, or other insects; small worms and flies were also 

 noted, but none was specifically identified. 



WOODPECKERS. 



This family comprises a highly specialized group of birds, 

 the more typical of which are peculiarly fitted to secure their 

 food by digging into the trunks or limbs of trees, in search 

 of ants and other wood-boring insects which cut channels 

 under the bark and into the wood. The feet of most Wood- 

 peckers are four-toed, two toes being disposed in front and 

 two behind. Some species, however, have but three toes. 

 The tail is composed of stiff, hard feathers, with strong shafts. 

 These modifications of the foot and tail assist the bird in 

 climbing perpendicularly and in clinging to the bark of trees. 

 While climbing or feeding, the two pairs of toes with their 

 strong, sharp claws enable the bird to grip the bark and hold 

 on, while the strong, sharp-pointed quills of the tail serve 

 as a brace or support. The bird is thus more fully equipped 

 for climbing than a telegraph lineman. The claws and tail 

 take the place of the man's hands and spurs. But the Wood- 

 pecker's tools for drilling into the wood and extracting its 

 living food are more wonderful than its climbing apparatus. 



If any one who had never heard of a Woodpecker were to 

 be told that the bird drilled holes into the solid wood by 

 beating its head against a tree, he would be likely to regard 

 the story as fiction. Nevertheless, that is very nearly what 

 the Woodpecker actually does. The highly specialized appa- 

 ratus that will permit of such constant hammering of beak 

 and head against the trees without producing concussion of 

 the brain, or the least inconvenience or injury to the bird, 

 is certainly among the most wonderful features of bird 

 anatomy. 



A moment's reflection will convince any one that, unless 

 the Woodpecker's skull were built on an unusual plan, it 

 could not withstand such hard and continuous hammering. 

 If we watch a Woodpecker drilling, we shall see that he 



