THE BONES. 
47 
by many scarcely known to exist. The great diffe- 
rence between the limbs of birds and human beings 
consists in this, that what we are apt to term the leg of 
a bird is, in fact, the part which answers to our ancle. 
This will be easily seen by a little closer examination. 
Let us look, then, at the joint b in the two figures ; 
in the human figure it is at once seen to be the 
knee, and on referring to the same letter in the leg 
of the bird, we shall find that it is the true knee 
also ; for supposing it to kneel, that is, to bend its 
leg, so that the fore part of the joint should touch 
the ground, it can only do so at the joint b, it being 
as obviously impossible from the structure of the 
joint c, that it could bend the part c d forwards, so 
as to make the front part of the joint c touch the 
ground, as it would be for us to bend the leg-bone 
forward below the knee. The remaining portion, 
then, c d of the bird's limb, when compared with 
the similar part in our own leg, ought to be called 
its ancle, and so in truth it is. This may be 
more easily understood, by referring to a very extra- 
ordinary looking bird, sometimes, though very rarely, 
seen in England, called the Stilted Plover ( Chara- 
drius himantopus), from the strange disproportion 
of its legs, a figure of which is annexed, and of 
which No. 2 may be considered as an illustration ; 
in which an inexperienced observer will at first 
sight not easily persuade himself, that c d is 
nothing more than the ancle, and the back part of 
the joint c its heel ; yet so it is, as the reader will 
at once perceive in the following figure, where the 
bird is represented in its usual, and what may be 
called, kneeling position ; the real knee, corresponding 
