RUMINANTIA, in the zoological system of Curler, and of almost all recent natural ists, the name given to an order of mammalia called pecora by Linmtus, an extremely well-defined natural order, among the individuals of which the habit of rumination or chewing the cud is universal and almost peculiar. The ruminantia axe all strictly and exclusively herbivorous, and exhibit a great similarity of structure. They have no incisors in the upper jaw, the front of which is occupied by a callous pad. "The grass is collected and rolled together by means of the long and movable tongue; it is firmly held between the lower cutting teeth and the pad, the cartilaginous upper lip assisting in this; and then, by a sudden nodding motion of the head, the little roll of herbage is either torn or cut off, or partly both torn or cut."—Youatt. In the lower jaw there generally appear to be eight incisors; but the two outer are more properly to be regarded as canines, and in the canzelidm they assume the ordinary canine form. Some of the ruminantia have canine teeth in the upper jaw, and some are destitute of them. In front of the molar teeth there is a long vacant space in both jaws. The molars are six on each side in each jaw; their surface exhibits crescent-shaped ridges of enamel. The head is elongated, the neck is always of considerable length, the eyes are placed at the side of the head, and the senses of smell and hearing, as well as of sight, are extremely acute. The head is in many ruminantia armed with horns, which in sonic are found in both sexes, in some only in the male, whilst in 'others they are wholly wanting; and the absence of them characterizes varieties of some species, as the sheep and ox, in which they are ordinarily present. The horns differ very much in different families, even in their structure, some being hollow (true horns), some solid (antlers). All the four limbs are terminated by two large toes, which are hoofed. Behind the hoof are always two small spurs, rudimentary toes. The metacarpal and the metatarsal bones are united into one, called the cannon bone: The legs are rather long, and the spinal column is very flexible. The brain of the ruminantia is small, and they do not exhibit much intelli gence; nor are they distinguished by any remarkable instincts; and though easily tamed, they are scarcely susceptible of any kind of training or education. Very few, however, of the numerous species of ruminantia have been truly domesticated, and probably much is yet to be done in this way.
The ruminantia are generally gregarious; they are distributed over almost the whole world; but none are natives of Australia. They are found both in the warmest and the coldest regions. The flesh of all the rnminautia is fit to be used for human food; the fat (tallow) hardens more on cooling than the fat of other animals, and even becomes brittle. The fat, hide, horns, hoofs,•rtir, bones, entrails, blood, and almost all parts are u..,eful to man.
The intestines are long in all the ruminantia. The crecum is also long. The complex stomach, adapted to rumination, requires a more particular description. The stomach consists of four distinct bags or cavities. The first of these, into which the gullet or esophagus enters, is, in the mature animal, by far the largest, and is called the paunch (Lat. rumen). Into this the chief part of the food passes. It is lined with a thick mem
brane, presenting numerous prominent hard papillae, secreting a fluid in which the food is soaked." The second cavity is the honey-comb bag (Lat. retieutum), so called from its being internally covered with a net-work of cells, like those of a honey-comb. In Scot land it is known tl,s the king's hood. This second cavity, or stomach, has also a direct communication with the esophagus, and fluids seem in general to pass immediately into it, but sometimes or partly also into the other cavities; and it is here that the cells for retaining water are chiefly found in the camel. The third cavity, or stomach, is the nmavyplies (Lat. psalterium), so called because its lining membrane forms many deep folds, like the leaves of a book, beset with small hard tubercles. This also communi cates directly with the esophagus, by a sort of prolongation of it. The leaves of the membrane seem to serve for the absorption of superfluous fluid from the food. Finally. the food passes into the fourth cavity, which is of a more elongated form than any of the others, and is next in size to the first. This is called the reed or rennet (Lat. abom a su 8). It may be considered as the true stomach, homologous—if any one of the four parts can he so regarded—to the simple stomach of mammals in general. It is lined with a velvety mucous membrane in longitudinal folds. It is here that the gastric juice is secreted. In young animals it is the largest of the four cavities, and it is only when they pass from milk to crude vegetable food that the paunch becomes enlarged, and all the parts of the complex stomaei conic fully into use. It seems to be by a power of what may he called instinctive volition that the animal directs what passes through the gullet into the first cavity, the second, or even the third. It has been found by M. Flonrens, who male many experiments on this subject, that the food consumed by ruminants passed efiietlyinto the first cavity, but part of it also at once into the second, and even, when it was given in a mashed or in a much comminuted state, into the third.
The particular means by which hastily swallowed food is brought from the paunch, formed into pellets at the base of the esophagus, and brought up into the mouth for rumination, or second and more thorough mastication. are not yet Very thoroughly understood, notwithstanding the patient investigations of M. Flourens. He ascribes the formation of the pellets, however, to the action of the muscular duct which connects the esophagus with the second and third stomachs, and the power which the animal has of closing or opening at will the orifices of these cavities.
Chewing of the cud is very generally performed in an attitude of repose, and evidently affords great pleasure to the animal.
The ruminantia are arranged by naturalists in seven families, all very natural eamelithe (see CAMEL), MOSChid0 (see INIUSK), CerthiCV (see DEER), camelopardidts (see GIRAFFE), untiopiche (see ANTELOPE), boridw (q.v.), and caprida3 (q.v.). The most impor tant genera and species are separately noticed.