When, with its thick, palatable flesh, it is cooked and placed on the
table, it is known as the "drumstick"--a favorite part of the fowl with
hungry boys, vying, in their minds, with the "white meat" of the breast.
This important segment of the limb is composed of two bones, the larger
of which is called the tibia, the smaller the fibula. At its lower end
the tibia forms what is known as the ankle joint by articulating with
the next long bone, which is commonly called the tarsus, although the
proper name would be really metatarsus. It is not often that this bone
is covered with flesh, and therefore it seldom finds its way to the
table. Properly speaking, it is the larger part of the bird's foot,
reaching obliquely upward and backward from the roots of the toes to
the heel. If you will lift yourself upon your toes, holding your heels
in the air, you will be able to form a correct idea of what the bird is
doing whenever it stands or walks or perches.
The toes are fastened by means of well adapted joints to the lower end
of the tarsus, and form what is popularly regarded as the bird's foot.
When spoken of separately, these toes are called digits, and when
spoken of collectively, they are called the podium. They are composed
of small bones called phalanges or internodes, which are jointed upon
one another like the several parts of the human fingers. The digits
can be spread out for walking purposes, or bent around so as to clasp
an object. The outer bone of each digit almost always bears a nail or
claw, which is sometimes very strong and hooked, as is the case with
the birds of prey, while in other species it is only slightly curved
and is not meant as a weapon of offense or defense, but chiefly to
enable the bird to "scratch for a living."
How do the birds, in perching and roosting, retain their hold so long
on a limb without becoming weary? They do not need to make a conscious
effort to do this, but are held by the mechanical action of certain
muscles and tendons in the leg and foot. Of course, the bird can also
control these muscles by an act of its will, but a large part of their
action is automatic. In some species there is a muscle called the
ambiens, which has its rise in the pelvis, passes along the inner side
of the thigh, whence its tendon runs over the apex of the angle of the
knee joint, and down the leg till it joins the muscles that flex the
toes. Now when the bird's leg is bent at the joints,
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