246 USEFUL BIRDS. 
draws back his head and body to the greatest possible dis- 
tance from the tree, and then strikes with all his force, send- 
ing his strong beak powerfully into the wood. The skull of 
the typical Woodpecker is very thick and hard. Its connec- 
tion with the beak is strong, but at the same time springy, 
and somewhat jar-deadening. The membrane which sur- 
rounds the brain is very thick and strong. 
Maurice Thompson says that no person can doubt, after 
an examination of Woodpecker habits, that the birds are 
hard of hearing. He apparently believes that the continual 
concussion has deadened this sense. However this may be, 
it has not interfered with the bird’s sight, which seems pre- 
ternaturally keen. 
The bill is shaped somewhat like a stout chisel, and is used 
as one. It strikes out small chips, and so drills its way, if 
necessary, even to the 
heart of the tree; but 
the most highly spe- 
cialized organ of the 
Woodpecker is its 
tongue, which serves 
as an accessory to the 
bill in bringing to 
Fig. 103.—Skull and tongue of Woodpecker. light the deep-lurkin g 
(From Samuels.) - 
enemies of the tree. 
The subjoined cut of the Woodpecker’s skull (Fig. 103) 
shows the tongue slightly protruding from the open beak. 
Ordinarily the tongue lies in the depression of the lower 
mandible. It is slender, nearly round, and its upper sur- 
face is covered with very minute 
spines, directed backward ; its tip 
is as hard as horn, with many 
strong barbs, which make of it @ pig i904, —spearlike tongue-tip 
weapon more effective in its way — of Downy Woodpecker, much 
C enlarged. 
than a fish spear. The machinery 
for thrusting it forth is most perfect. The bone of the 
tongue, called the hyoid, has two branches which pass down- 
ward and backward from the lower jaw, up and around the 
back of the head, and over the top of the skull, where they 
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