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PICTURES OF BIRD LIFE. 
economy, inasmuch as the tail-feathers are very hard, and terminate in points, 
so as when pressed against the bark to assist the bird in climbing or maintaining 
its place on a tree. Yarrell points out a further peculiarity in the Woodpecker’s 
structure—the small-sized keel of its breast-bone. The advantage of a narrow 
shallow keel is immediately apparent on looking at a representation of the skeleton 
in a climbing position. The low keel, allowing the bird to place its body close 
to the tree, brings its centre of gravity in a perpendicular line before the points 
of support, and thus materially diminishes the labour of, and the strain upon, 
the muscles of the legs and thighs. Birds of this family are found almost all 
over the world, except in the Australian region, being evidently required in the 
order of nature wherever large forests exist. Their plumage is very varied; the 
young have, in some of the species, a plumage peculiar to themselves. Although 
the mission of the Woodpeckers is undoubtedly to clear trees of noxious insects, 
Mr. Darwin points out, as instances of changed habits, that in North America 
t 
there are Woodpeckers which feed largely on fruit, and others with long wings 
which chase insects while flying. On the plains of La Plata, too, where hardly 
a tree grows, another Woodpecker ( Colaptes ), possessing all the essential points 
in the structure of the family, does not climb trees, and makes its nest in a 
bank ; but in other wooded districts it returns to the usual tree-climbing habits 
of the family. As a caution to hasty inferences in the structure and colour of 
birds, the same naturalist acutely observes that “ if Green Woodpeckers alone had 
existed, and we did not know that there were many black and pied kinds, I 
dare say that we should have thought that the green colour was a beautiful 
adaptation to conceal this tree-frequenting bird from its enemies.” The colours of 
all the birds comprising this family are, however, well adapted to the shades and 
hues of the woodlands in which they are chiefly found. 
Our Woodpeckers are four-toed, but there is a very common species (Ficus 
tridactylus ) inhabiting the vast forests of the north of Europe, Asia, and America 
which only possesses three toes. Its plumage is beautifully pied in black and 
white, the top of the head being, in the male, of a golden-yellow colour, but in 
the female silvery-white variegated with fine black streaks. Insects and their larvae 
and fruit form its food. The large Ivory-billed Woodpecker (F. principalis ), which 
may be regarded as the typical bird of the family, is a native of Brazil and Mexico. 
There are also beautiful Woodpeckers in India. 
Having now given a sketch of the Woodpecker family, we can turn our 
attention to the British members of it. Several others have been called British, but 
