7. This is the nature of the stomach of animals with horns, and no teeth in the upper jaw. But they differ from each other in the form and size of these parts; and because the œsophagus is sometimes united to the middle, and sometimes to the side of the stomach. Most animals which have teeth in both jaws have but one stomach, as the man, dog, bear, lion, and the wolf. The thos[72] has all its intestines like a wolf. All these have but one stomach, to which the bowel is united. But in some of these the stomach is larger, as the hog and the bear; that of the hog is marked with a few smooth lines. In other animals the stomach is less, not indeed much larger than the intestine, as the dog, lion, and man. In the forms of their bowels other animals are divided into two classes, resembling these types; for in some the stomach resembles a dog's, in others a hog's, both the greater and lesser animals in the same way; and the stomachs of various animals differ in size, form, thickness, thinness, and the position of the junction of the œsophagus. [72] Felis onza, perhaps also canis aureus. 8. And the nature of the bowels differs in the before-named animals, those, namely, which have not, and those which have teeth in both jaws, in size, thickness, and folding. The intestines of the ruminants are all large, and so are the animals themselves; there are a few small animals of this class, and there is no horned animal which is very small. And some have appendages to the intestines, for none of the animals with teeth in both jaws have straight intestines. There are enlargements in the bowels of the elephant, which give it the appearance of having four stomachs; in these the food is detained, and apart from these there is no receptacle for the food. Its intestines are very like those of the hog, except that the liver is four times greater than that of the ox, and other parts also; the spleen is small in proportion to its size. 9. The stomach and intestines of oviparous quadrupeds bear a similar proportion to each other, as in the land and marine tortoise, the lizard, and both kinds of crocodiles,[73] and similar quadrupeds; for they have one simple stomach, in some it is like that of the hog, in others like that of the dog. [73] Crocodilus niloticus and Lacerta stellio. 10. The class of serpents in almost every part of their body resemble the saurians, which have feet, and are oviparous, if we add to their length, and take away the feet; for snakes are covered with scales, and have their upper and lower parts like saurians, except that they have no testicles, but, like fish, two passages united in one, and a large and cloven uterus, but in other respects their intestines are so like those of saurians, except that from their elongated figure their intestines are long and narrow, that they might be mistaken for them, from their similarity.