104 ZYGODACTYLI. PICUS. WooprEcker. 
feeds chiefly upon the insects that live in the bark, or that 
form their receptacles by boring the decayed wood of trees ; 
which last it is well enabled to reach by the aid of its strong 
and wedge-shaped bill, penetrating without difficulty to the 
nidus of the larva. Its long vermiform and extensile tongue 
is also of service in extracting the smaller insects from the 
crevices of the bark, where they so often lie concealed. This 
singular instrument, in addition to a glutinous substance con- 
stantly exuding from its surface, 1s armed at the point with 
sharp reflected bristles, acting like the barbs of an arrow in 
preventing the escape of its prey. The above description 
shews the tongue to be well adapted fcr the capture of the 
ant, an insect of which the green woodpecker is particularly 
fond, and on which account it is oftener seen on the ground 
than the other species. Under a deficiency of its usual food, 
it will eat nuts. It scales the trunks and branches of trees 
with facility and swiftness, either in an upright or a spiral di- 
rection; but none of the species that frequent this country 
are able,. as has been asserted, to descend, as well as to as- 
cend, with equal readiness. When they wish to descend, it 
is effected by moving backward, as I have repeatedly ob- 
served. ‘This peculiarity of motion seems to be the conse- 
quence of the structure of the bird, in which the preponder- 
ance is thrown considerably forward. 'The legs of this bird 
are short and strong 
5? 
the form of the claws, it is enabled to maintain a firm hold in 
and, by the disposition of the toes, and 
a perpendicular direction, in which position it is materially 
assisted by the stiff-deflected tail-feathers. It lays its eggs in 
trees, perforating a round hole, sometimes of considerable 
depth ; for which purpose it selects those in a decaying state, 
proach of changes of weather than our own. That domestic animals ex- 
hibit sometimes irritability, and sometimes heaviness, previous to such 
changes, is very evident. Our observations on the feathered tribe are of 
“course more limited; but such influence has heen remarked in the habits 
of domestic pigeons, and in rooks, and I have before noticed a similar effect 
in my account of the Golden Kagle. 
