THE WOODPECKERS TONGUE. 451 
borders of large forests. Insects and their larvee form their nourish- 
ment; which they seek in the trunks and clefts of trees. ‘Their 
tongue is wonderfully suited for this purpose. It is very long, 
and, by a peculiar mechanism, can be projected out far enough to 
reach objects three or four inches away. The beak is terminated 
by a horny point bristling with small hooks. In many species it is 
overlaid with a sticky humour, secreted. by two voluminous glands, 
the effect of which is to catch 
the insects which it touches. 
Whenever the bird darts this 
tongue into the crevices, it 
draws it out more or less laden 
with insects. If it perceives 
an insect that it cannot reach 
by means of this organ, it has 
recourse to its strong beak : 
striking the tree with redoubled 
blows, it cuts the bark, breaks 
an opening, and seizes the 
coveted prey. It often also ~ 
taps with its beak to sound LAs NN ANN 
a tree, and assure itself that {| a eS 
there is no recess in the in- A 
terior which would serve as a 
refuge for its prey. If the 
trunk is hollow, it examines 
all parts to find an entrance 
to the cavity. When it has 
discovered it, it introduces its 
i 
4 \ 
PAL h\ 
Ay! i 
Fig. 177.— Downy Woodpeckers. 
- 
tongue ; and if the canal is not aN i 
large enough to permit it to + i Ne 
D : : vi Mi ‘ ett 
explore the hiding-place with 
success, it increases the size of 
the aperture. It is not only 
to seek for food that Woodpeckers make holes in trees, but also to 
form secure hiding-places for their nests. Some species, it is true, 
select the anfractuosities which they find, but others hollow out their 
resting-places according to their tastes. When such is the case, they 
select soft-wood trees, such as willow, aspen, &c. The cavity which 
they bore to where the nest is placed is generally so oblique and so 
deep that perfect darkness must surround them. This is doubtless a 
measure of security against small mammals, especially the rodents, 
