third stomach. During the short time that it probably remains between the folds of this division, it is still further prepared for the process of digestion in the true stomach. The structure of the groove thus proves that the operation is subject to the will of the animal, and it is expressly stated of some men, who have had the power of ruminating, (instances of which are not very rare,) that it was quite voluntary with them. "I have known," continues Blumenbach, "two men who ruminated their vegetable food; both assured me that they had a real enjoyment in doing this; which has also been observed of others: and one of them had the power of doing it, or leaving it alone according to circumstances."
The importance and interesting character of this operation, which is one of the most remarkable deviations from the ordinary economy of the Mammalia, will plead our excuse for the minuteness with which we have considered it.
The incisor teeth in the lower jaw are commonly eight in number, but in the upper are wanting; a callous pad, the hardened gum, receiving the pressure of the lower cutting teeth. Canines are found in some genera only. Six molars are on each side, both above and below, the crowns of which are marked with double crescents of enamel.
In by far the greater number of genera, true horns are found, at least in the male sex, which are bony prominences, projecting, one on each side, from the frontal portion of the skull.
The food of the whole Order is exclusively vegetable, and grass and similar herbage constitutes the greatest proportion of it. Hence their flesh forms wholesome and agreeable food to man, who
