Aristotle's History of Animals In Ten Books · Aristotle
CHAPTER VIII.
1. Birds also have many parts like the animals described above. For all these have a head, neck, back, and under parts of the body, and something resembling a breast. They have two legs, and thus resemble men more than other animals, except that the joints bend backwards like those of quadrupeds, as I said before. They have neither hands, nor fore-feet, but wings; herein they differ from all other animals. Again, the hip is like a thigh, large and united as far as the middle of the abdomen, so as to look like a thigh, when it is separated from the rest of the body; and the thigh where it is joined to the leg is another part. The class of birds with crooked claws have the largest thigh, and stronger breasts than others. 2. All birds have claws and many divisions of the foot; in most of them the toes are quite separate; but the swimmers have their feet covered with a web, but even these have distinct and jointed toes. All birds that fly high in the air have four toes; and, generally, these are placed three forwards, and one backward, like a heel; a few birds have two toes turned forwards and two backwards, as the bird called jynx.[37] This bird is somewhat larger than the spize,[38] and is variegated in appearance. The formation of its toes is peculiar, and so is that of its tongue, which is like a serpent's. This it can project from its mouth, as much as the width of four fingers, and draw it in again. Like a snake it can turn its neck quite round, whilst the rest of its body is perfectly still. It has large claws, like those of the colius,[39] and it hisses with its voice.
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