Page images
PDF
EPUB

“ Others, filled with pasturage, gazing sat,

Or bedward ruminating."--Miltox,

disposed to imagine that rule and compass had been employed in their formation. These alternate bands are narrow, parallel, and exactly separated; they extend not only over the body, but the head, thighs, and legs, and even over the ears and tail. They follow so exactly the contours of the different parts, enlarging more or less according to the development of the muscles, and the roundness of the different forms, that they exhibit the entire figure in the most advantageous point of view. In the female these bands are alternately black and white, in the male they are black and yellow, but always of a lively and brilliant tint. They also rest upon a ground of short, fine, and copious hairs, whose lustre considerably augments the general beauty of the colours.*

ORDER IX.-RUMINANTIA.

507. Why are the animals of the ninth order called ruminants ?

Because they chew again the food which has been swallowed, slightly masticated. The word is derived from the Latin rumino, from rumen, the cud.

508. Why do numerous herbivorous animals chew the cud ?

Because in a state of nature they are liable to be surprised and preyed upon by their carnivorous enemies while feeding. They are therefore endowed with stomachs capable of receiving a large quantity of food in a crude state, and with the power of returning it again, to be brought under the action of the teeth, when the animal has retired to a place of comparative security.

509. The class of ruminants feed on the coarser kind of herbage where they are in abundance; but the actual nutritious matter is small in quantity compared with the mass. There is, therefore, an obvious necessity for a more complex apparatus to extract the smaller proportion of matter capable of being animalized; hence the various preparations for digestion. When the mass is digested, the nutritious part is still small in proportion to the whole; and, to permit that smaller part to be prepared and carried into the system, the intestinal canal must be long and complex, offering resistance to the rapid descent of the food, and giving it lodgment; and thus there is always a correspondence between the complication of the stomach and the length of the intestines, and between both and the nature of the food.

It is further remarkable, that when animals of the same species live in different climates, where there is more or less abundance of vegetable food, there is an “ The condemned English

* Buffon,

Sit patiently, and inly ruminate
The morning's danger."-SHAKSPERE.

adaptation of their digestive organs. When it is abundant, the configuration of the intestines which is intended to delay its descent is less complex; when the food is scarcer, the intestine is longer, and the obstruction afforded by the valves is greater.

510. How is the process of rumination conducted ?

The stomachs of ruminating animals are divided into four chambers, of which the first three are so disposed that the aliment can enter at the will of the animal into any one of them.

511. The first stomach, or paunch, is divided outwardly into two bag-like appendages at its extremity, and is slightly separated into four parts on the inside. Here are received the masses of herbage, rudely broken up by the first mastication. But no true digestion occurs here; only a slight maceration, such as water would produce in a degree of moderate heat. The herbage is afterwards transmitted in this state to the second stomach, or honeycomb-bag, so called from the honeycomb similarity of the surface of its coats. Here the herbage is arrested, and compressed into small maws, or balls, which are thence returned at leisure successively to the mouth for re-mastication.

During this operation the animal remains in a state of repose until all the herbage swallowed has undergone the action of the molar teeth a second time. The aliment thus re-masticated is transmitted into the third or smallest stomach, the laminæ on the walls of which bear a resemblance to the edges of the leaves of a book when slightly opened. From the third stomach the food is transmitted into the fourth, which is next in size to the first stomach, or paunch, and with an internal villous coat similar to that of the human stomach, with large longitudinal wrinkles. This last is the chief organ of digestion.

The first three stomachs are connected with each other, and with the esophagus, or throat, 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 æsophagus into the third stomach. The functions of this very singular part vary, according to its use as a simple groove, or a closed canal. In the first case, the grass, &c., is passed, after a very slight degree of mastication, into the paunch, as into a reservoir. Thence it goes, in small portions, into the second stomach, from which, after further maceration, it is propelled into the esophagus, and conveyed by a muscular backward motion into the mouth.

It is here ruminated, and again swallowed, during which the groove is closed, and the food, after this second mastication, is thereby conducted directly into the “ By Cinthia's light, and on the pleasant lawn,

The wanton fairy we were wont to chase,
Which to the nimble cloven-footed fawn,

Upon the plain durst boldly bid the race."-DRAYTON.

third stomach. During the short time which it stays in this situation, between the folds of the internal coat, it is still further prepared for digestion, which is completed in the fourth or digestive stomach. The closing of the groove, as already described, which determines the chamber or stomach into which the food shall be passed, is an act of will on the part of the animal. While young ruminants remain at the teat, and live upon milk, the fourth stomach is the largest. The first stomach, or paunch, only developes itself into its enormous volume, in proportion as it receives supplies of herbage, which increases with the growth of the animal.

It is remarkable that this faculty of rumination, so important to the animals in their wild state, is no less valuable in their domesticated condition :

Cows stand patiently while being milked, chewing the cud the while, and deriving gratification therefrom.

Being driven to market, they are able to take with them a store of food, which serves to mitigate their hunger during a period of abstinence from grazing.

Sheep disperse their flocks and fill their paunches, and then draw together to chew the cud, by which they derive warmth during cold hours of the night, and obtain shelter from occasional storms.

512. Why have all animals which chew the cud cloven feet?

Because the splitting of the foot into two parts adds to its spring and elasticity, prevents its sinking deeply into soft ground, and permits it to be more easily withdrawn. As these animals usually feed upon pastures and other fertile places, it will be seen that this conformation of the foot not only favours the movements of the animal, but renders the tread less destructive to vegetation.

513. What is the difference between the dromedary and the camel ?

The dromedary, or Arabian camel, has one hunch on the back ; the Bactrian camel has two hunches. The dromedary is a lighter variety of camel, bearing much the same relation to the ordinary camel as a race-horse or hunter does to a cart-horse. It is used principally for journeys in which dispatch is required, and carries only a single rider or a very light burden. It can maintain a trot at the rate of from six to eight miles an hour, for twenty-four hours consecutively; and a gentle easy amble of five miles an

“ Or camels knelt To take their loads, or borsemen scour'd the plain."-CAMPBELL.

hour can be kept up by the dromedary for several days and nights almost uninterruptedly.

514. Why are the cameland the dromedaryso called ?

[graphic]
[blocks in formation]

515. Why are the camel and dromedary furnished with callosities (or hardnesses of the

skin); namely, one on the breast, and two on each side of the fore legs, and one on each side of the hind legs ?

They are thus endowed because they do not lie on their sides, but rest and sleep with their knees bent under their bodies, and their breast upon the ground; these parts require to be particularly guarded and strengthened, to resist the weight of the body, which is brought to bear, both when the animal assumes its attitude of repose, and when it rises up.

516. Why is the neck of the camel of great length, and extremely flexible ?

Because this structure allows the animal to crop leaves from the

“ The trees, devouring caterpillars burn:

Parch'd was the grass, and blighted was the corn."-DRYDEN.

tall trees upon which it feeds, and also to bend the neck when drinking from springs, and other places where water is found ?

517. Why has the dromedary a hump upon its back ?

This hump is an accumulation of a peculiar species of fat, which is not liable to be acted upon by the great heat to which the animal is exposed. It consists chiefly of stearine, or hard fat. It is, in fact, a store of nourishment beneficently provided against the day of want, to which the animal in a wild state is often exposed, and from which he is not entirely exempted in a state of domestication. The dromedary or camel can exist for a long period upon this hump alone, without any other food ; and it does not die of want until the hump has been entirely absorbed, and applied to the nourishment of the system.

518. Animals which exist chiefly upon vegetable matter, and which are subject to seasonal vicissitudes in their supply of food, all make accumulations of fat on some part of their bodies, as a provision against the failure of the supply of food ; and their tendency to this habit is exactly in proportion to the need they have for it. The parts of the body in which this accumulation is made, and the consistency of the accumulated substance, are both very important points in the geographical distribution of animals. If the animal winters in cold latitudes, the accumulation of fat is generally distributed over the surface, and the substance is of a soft and oily nature. If, on the other hand, it inhabits warm latitudes, the mulation is chiefly composed of a crystallizable fat, and is generally situated on some part of the animal where it is least likely to interrupt its labour and progress.

accu

519. Why is the formation of the stomach of the camel and the dromedary admirably adapted for enabling the animal to take long journeys over parched deserts ?

Because the stomachs of these animals are capable of retaining large quantities of water unchanged for a considerable length of time. A number of distinct sacs are observed to lie between the membranes of the second stomach, and to open into the stomach near the top by small square apertures. Through these orifices, after the stomach is full, the annexed bags are filled ; and

« PreviousContinue »