THE BONES. 45 



Here we see the legs both divided into three 

 parts, exclusive of the actual foot. The first from 

 A to B; the second from B to c; the third from 

 c to D. Now, without attending carefully to these 

 divisions, we might be apt to conclude, that birds 

 have one more division than human beings: but 

 this is not the case. The mistake on our parts 

 arising, from the prevailing opinion, that the part c 

 D in the bird's limb, is the part which corresponds 

 with what we usually term the leg, namely, B to c, 

 that is, from our knee to our ancle; whereas, the bone 

 B c in the limb of the bird is, in fact, its real leg- 

 bone. For its thigh we must look still higher, hidden 

 as it usually is amongst the feathers, and, probably, 

 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 



