ORDER VII. RUMINANTIA.
(Ruminating Animals.)
The distinctive characters of the animals of this Order are so strongly marked as to have been recognised in very early times. Even at the era of the Deluge we find a certain number of animals separated from the rest as "clean;" and at the giving of the Law these are defined in the following terms:—"Every beast that parteth the hoof, and cleaveth the cleft into two claws, and cheweth the cud,—."[1] The Camels, it is true, exhibit some deviation from the common characters, forming the link of connexion with the order we have just relinquished; but with this trifling exception the cloven-footed Ruminants constitute a group of Mammalia remarkably compact, natural, and well-defined.
Each of the feet is terminated by two toes, encased in two hoofs, sharp-pointed, and presenting a flattened surface to each other, as though a single rounded hoof had been cleft. Behind the hoofs, there are two small spurs, which are the rudiments of lateral toes.
The faculty of rumination, or chewing the cud, is the most remarkable possessed by these animals: the vegetable food, swallowed almost as taken into the mouth, is returned after a while to undergo a second mastication, so as to fit it for a more perfect digestion. In connexion with this power we must mention the complex character of their stomachs, which are four in number, each having a distinct structure and function; and the first three of which are so disposed that the food can enter at the will of the animal into either of them, the gullet terminating at the point of communication.
The first stomach or paunch (rumen) is, in the full grown animal, the largest of all, but not so in the new-born young. It is externally divided into two bag-like appendages at its extremity, and it is slightly separated into four parts internally. The interior surface is beset with innumerable flattened warts (papille). The mass of herbage, rudely bruised by the teeth, is received into this stomach, whence it is transmitted to the second, called the honey-comb bag (reticulum). This is small and globular, and may be considered as an appendage to the paunch, but is distinguished from it by the laminæ which stand up from its inner surface, dividing the whole into elegantly-arranged hexagonal cells, like those of a honey-comb. The food is here arrested, moistened, and compressed into small pellets, which are successively returned to the mouth to be rechewed, an operation usually performed during the repose of the animal, and evidently attended with much enjoyment.
Thus completely masticated, it again passes through the œsophagus, and is received by the third stomach, called the manyplies (psalterium), the inner coat of which is also set with lamine, but running down longitudinally parallel with each other, so close and numerous as to resemble the leaves of a book. In the sheep there are about forty of these leaves, and in the ox as many as a hundred.
Thence the food passes into the fourth stomach, commonly known as the red (abomasus), which is of considerable size, of a lengthened pear-like form, and having a hairy inner surface, with many large longitudinal wrinkles. This is the seat of digestion, properly so called: in the sucking young, it is the largest of the four.
The mode of acting of this complicated organ, Blumenbach has explained. The first three stomachs are connected with each other, and with a groove-like continuation of the gullet (æsophagus), in a very remarkable way. The latter tube enters just where the paunch and the second and third stomachs approach each other; it is then continued with the groove, which ends in the third stomach. This groove is therefore open to the first stomachs, which lie to its right and left. But the thick prominent lips which form the margin of the groove admit of being drawn together, so as to form a complete canal, which then constitutes a direct continuation of the gullet into the third stomach. The functions of this very singular part will vary according as we consider it in the state of a groove or of a closed canal. In the first case, the grass is passed, after a very slight mastication, into the paunch, as into a reservoir. ‘Thence it goes in small portions into the second stomach, from which, after a further maceration, it is forced into the gullet and thus returned into the mouth. On being again swallowed, the groove is shut, and the morsel of food is thereby conducted into the third stomach. During the short time that it probably remains between the folds of this di- vision, 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 remark- able 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 in this respect is more indebted to the Ruminantia, than to the whole animal kingdom besides. Their milk also, both in a crude state and in the form of butter and cheese, forms an important article of human diet; and their fat, (which becomes very solid when cold,) their horns, hides, hair, or wool, and bones, are all turned to useful account in the arts of civilized life. Some of the genera emulate, if they do not surpass, even the Equidæ, as beasts of burden and of draught.
The species of this order are widely scattered all over the world, with the exception of Australia. They are arranged in five families, Camelidæ, Moschidæ, Cervidæ, Capradæ, and Bovidæ.
- ↑ Deut. xiv. 6.