Chapter I

1. Of the parts of other animals some are common to them all, as I have said before, and some belong to particular classes, and they agree and differ in the manner often before mentioned. For almost all animals which differ in kind, have also their parts different in form, and there are some which have only a proportionate resemblance, but differ in kind, and others agree in kind, but not in form, and many parts belong to some which others have not. Viviparous quadrupeds have a head and neck, and all the parts of the head, but they differ from each other in their forms. The lion has one bone in the neck, but has no vertebræ, and when laid open its internal parts are like those of a dog.

2. Viviparous quadrupeds have fore-legs instead of arms, and in all quadrupeds, especially those which have the fore-feet much divided, they are analogous to hands, for they use them as hands, and the left legs are less at liberty than in men, except in the elephant, and this animal has the toes less perfectly jointed, and its fore-legs much larger than the hind ones; it has five toes, and short ankles to its hind legs. It has a trunk of such a nature and length as to be able to use it for a hand, and it drinks and eats by stretching this into its mouth; this also it lifts up to its driver, and pulls up trees with it; with this organ it breathes as it walks through the water. The extremity of the proboscis is curved, but without joints, for it is cartilaginous.

3. Man is the only ambidextrous animal. All animals have their chest analogous to man, but not similar to his, for he has a wide chest, and theirs is narrow: no animal but man has pectoral mammæ; the elephant has two mammæ, but not on the breast, though they are in that direction.

4. All animals, excepting the elephant, bend both their fore and hind legs in contrary directions, and also contrary to the way in which a man's limbs are bent. For in viviparous quadrupeds, except the elephant, the joints of the fore-legs are bent forwards, and those of the hind-legs backwards, and they have the hollow part of their circumference opposite to each other: the elephant is not constructed as some have said, but is able to sit down, and bend his legs, but, from his great weight, is unable to bend them on both sides at once, but leans either to the right side or the left, and sleeps in this position, but its hind legs are bent like a man's.

5. In oviparous quadrupeds, as the crocodile, lizard, and such like, both the fore and hind legs are bent forwards, inclining a little to the side, and likewise also in other animals with more than four feet, except that the middle joint of their last pair of legs is always doubtful, and is rather bent towards the side. And man also has both the flexures of his limbs in the same direction, and those of his arms and legs contrary to each other, for he bends the arm backwards, except that the external part of the arm is a little inclined inwards, towards the side; the legs bend forwards.

6. No animal bends the joints both of its fore and hind legs backwards. The flexure of the cubitus and fore-leg is in a contrary direction to the flexure of the shoulder in all animals, and the flexure of the knee is contrary to that of the hip; so that since man bends his joints in the contrary direction to many animals, those which have such joints as man's also bend them in a contrary direction to many animals. Birds bend their limbs in a direction similar to that of quadrupeds, for being bipeds, they bend their legs backwards, and have wings instead of arms, or fore-legs, and these bend forwards.

7. The seal is like a maimed quadruped, for immediately beneath the scapula it has feet like hands, as are also those of the bear, for they are five-fingered, and each of the fingers has three joints, and a small claw: the hind feet are five-fingered, and each of the fingers has joints and claws like those upon the fore-feet; in shape they are very like the tail of a fish.

8. The movements of animals, whether they have four feet or more, are in the direction of the longer diameter of their bodies, and thus also they stand, the commencement of motion is always on the right side of their bodies. The lion and the camel, both the Arabian and Bactrian, walk with the hind-foot following the fore-foot on the same side, and this means that the right foot is not put before the left, but follows it.