Birds of Pennsylvania. 



123 



Order Pici. Woodpeckers. 



Family PICIDiE. Woodpeckers. 

 [Although Woodpeckers make no eiforts to build nests as other birds 

 generally do, they nevertheless prepare with great care and labor 

 equally suitable receptacles for their eggs and young. Woodpeckers 

 lay their eggs,* which are white, and usually number from four to six^ 

 on chips and bits ot rotten wood in cavities which they excavate with 

 their powerful and chisel-like or wedge-shaped bills, in the dead limbs 

 or trunks of trees. These holes or nesting places — often times dug to 

 a considerable depth — at the mouth are often just sufficiently large 

 to permit the birds to readily pass in and out ; from the entrance 

 downward the diameter of these wooden burrows increase in size. 

 The tongue of all our Woodpeckers, with one exception, viz : the 

 Yellow-bellied, is capable of being protruded beyond the point of the 

 bill to a considerable extent. The cornua or horns of the tongue ex- 

 tending backward, curl up over the back of the skull, and rest in 

 slight depressions designed for their reception ; these horns are en- 

 veloped in muscles by the action of which the tongue is thrust out. 

 This singular arrangement can easily be demonstrated by simply 

 taking hold of the end of the tongue of a Flicker we will say, and as 

 you move it backward and forward i)lace a finger on the top of the 

 bird's head, and at once a peculiar, worm like movement will be dis- 

 covered as the horns run back and forth between the skin and bony 

 covering of the head, beneath your finger. The end of the tongue in 

 Woodpeckers, other than the species above mentioned, is generally 

 furnished on either side with little barbs, very similar in appearance 

 to those found on small fish-hooks. In the Yellow-bellied Wood- 

 pecker the horns of the hyoid bone extend only to the base of the 



* The following measurements will show the average size of species which usually breed in this 

 State : Hairy Woodpecker, about 1 inch long and a little less than % wide. Downy Woodpecker, 

 about .80 of an inch long by about .03 wide. Pileated Woodpecker, about 1.25 of an inch long by 

 1 inch wide. Red-headed Woodpecker, a little over 1 inch long and about .85 of an inch in width. 

 Flicker, about 1.10 long and .90 wide. 



