THE DOWNY WOODPECKER 



food of woodpeckers is obtained from solid wood, Nature 

 has provided most of them with a stout beak having a 

 chisel-shaped point which forms an exceedingly effective 

 instrument. But the most peculiar and interesting point 

 in the anatomy of these birds is the tongue. This is more 

 or less cylindrical in form and usually very long. At 

 the anterior end it generally terminates in a hard point, 

 with more or less barbs upon the sides. Posteriorly the 

 typical woodpecker tongue is extended in two long, 

 slender filaments of the hyoid bone which curl up around 

 the back of the skull and, while they commonly stop be- 

 tween the eyes, in some species they pass around the eye, 

 but in others enter the right nasal opening and extend to 

 the end of the beak. In this last case the tongue is prac- 

 tically twice the length of the head. Posteriorly this organ 

 is inclosed in a muscular sheath by means of which it can 

 be extruded from the mouth to a considerable length, and 

 used as a most effective instrument for dislodging grubs or 

 ants from their burrows in wood or bark. Hence, while 

 most birds have to be content with such insects as they 

 find on the surface or in open crevices, the woodpeckers 

 devote their energies to those larvae or grubs which are 

 beneath the bark or even in the heart of the tree. They 

 locate their hidden prey with great accuracy, and often cut 

 small holes directly to the burrows of the grubs." ^ 



Mr. Forbush calls attention to the wonderfully con- 

 structed bead of a woodpecker "which is built so that it 

 can withstand hard and continuous hammering. The skull 

 is very thick and hard. Its connection with the beak is 

 strong, but at the same time springy, and somewhat jar- 



2 Bulletin No. 37, U, S. Dept. of Agriculture, Biological Survey. 



[67] 



