SONGLESS BIRDS OF ORCHARD AND WOODLAND. 247 
either pass into the nostrils and so on in channels down 
toward the end of the upper mandible of the beak, or, turn- 
ing to one side, coil themselves about the bony part of the 
eyeball. These branches of the hyoid are enclosed in 
sheaths which fit into a groove on the top of the skull. By 
means of this apparatus the tongue may be extended so 
that, in the Hairy Woodpecker, it may reach an inch and 
a half beyond the end of the bill. The tongue is propelled 
forward at need by powerful muscles, so that when the bird 
has drilled to the burrow of a boring beetle it can open the 
beak slightly, protrude the tongue, spear the insect and 
draw: it out and into the mouth. Birds which possess such 
implements for the destruction of boring insects must be 
immensely serviceable to man, for borers are difficult for 
man to control. 
The utility of Woodpeckers is now quite generally recog- 
nized by foresters, and by entomologists who study forest in- 
sects. Dr. A. D. Hopkins, the most active and experienced 
forest entomologist in the United States, is quoted by Dr. 
E. P. Felt as asserting that Woodpeckers are the most im- 
portant enemies of spruce bark beetles, and appear to be of 
inestimable value to the spruce timber interests of the north- 
east. Dr. Hopkins also states that Woodpeckers are the 
principal enemies of the destructive sap-wood borers. 
It is sometimes argued that Woodpeckers are of little use 
as protectors of trees, since they never dig into living wood. 
This reasoning is based on an error, due to 
lack of careful observation. Nuttall speaks 
of a Flicker that dug a nest hole eighteen 
inches deep in a green sassafras. Dr. Hop- 
kins figures a section of a living tree in which 
a hole four inches long, two wide, and five 
deep had been made by Woodpeckers in their 
search for boring larve. According to the Fig.105.—A pine 
annual wood rings around the entrance of the eae 
cavity, the tree recovered and lived at least fifteen years after 
the bird captured the borers. The work of Woodpeckers on 
living trees does not ordinarily attract much notice. They 
seldom need to dig far into live trees for borers, for most 
