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sandy soil of the deserts, in which this race of animals seem to have lived ever since its origin. The dentition of the prolonged jaws has certain peculiarities. The full number of incisors are present in youth, but in the upper jaw these disappear, except the outermost, which persist through life. Canines are present in both jaws, those in the lower jaw being nearly erect and pointed, whereas the incisors in that jaw are procumbent. The molars are of the selenodont type, and one or more of the anterior premolars are usually detached from the series and of a simple pointed form. The neck is very long and flexuous, and its vertebræ have certain peculiarities. The shoulders are high, and the hind quarters inclined to droop. The hinder part of the body, indeed, is much contracted, and the thigh bone is long, and vertically placed, so that the knee-joint is lower in position, and the thigh bone altogether more detached from the abdomen than in most quadrupeds. The tail is well developed and the skin is clothed with long shaggy hair, capable of being woven. The nostrils are high, and may be closed against the admission of dust; and the lips are prolonged and flexible. There are no horns or antlers in either sex. The interior anatomy is peculiar, principally in the character of the digestive organs, described in the article CAMEL. The family includes the camels, of the genus Camelus, with two species, which are confined at present to the Old World (see CAMEL) and the genus Llama-with two species that are restricted to the New World. See ALPACA; GUANACO; LLAMA.
Camelidæ, Fossil. The evolution of the camel (q.v.) through the Tertiary and Quaternary periods is nearly as completely known as that of the horse, and is hardly less instructive. The camels now inhabit central Asia and northern Africa, the llamas, South America. No
fossil camels or llamas are found in these countries in deposits much older than the Quaternary. But in the Tertiary strata of North America have been found a series of animals which appear to be the direct ancestors of this family, and connect them with the primitive hoofed animals of the earliest Eocene. The earliest member of this series, ancestral probably to the camels among other ruminants, is Trigonolestes of the Lower Eocene, smaller than a cotton-tail rabbit, with the complete series of incisor, premolar, and molar teeth, the molars of the primitive bunodont type (see BUNODONT) and four complete toes, the side toes very slender (one toe of the primitive five had already been lost), and the metapodials all separate. In the Upper Eocene stage, Protylopus, as large as a jack-rabbit, the molars have become selenodont (q.v.), as in modern camels, but with shorter crowns, and the side toes are represented only by splints. In the Oligocene stage, Poëbrotherium, as large as a gazelle, the molars have longer crowns, the splints are reduced to small nodules of bone, and the metapodials, though still separate, are closely appressed. In the Miocene stage (Procamelus, etc.) the metapodials are sometimes separate, sometimes united; the incisors and premolars are generally reduced in size, and the anterior ones often lost; and the form of the teeth and skull comes closer to the modern type. The Pliocene camels (Plianchenia, etc.) are still closer to the
modern type, all with united metapodials and reduced incisors and premolars, and at this epoch they spread to South America and the Old World, the gradual rising of the continents having made land connections between them about this time. During the Pleistocene epoch the camels all became extinct in their original home, although they still survive in the alien continents to which they had wandered.
The most remarkable peculiarity of the camels is the adaptation of the stomach, which enables the animal to go a long time without water (see CAMEL); palæontology gives no direct evidence of the evolution of this character. But the cushioned foot, equally an adaptation to desert life, is not indicated (by the form of the toe bones) in any ancestral camel previous to the Miocene, from which time it became gradually more marked. We may suppose, therefore, that the earlier ancestors of the camel were antelope- or deer-like in their habitat, and were gradually adapted to desert life.
Besides the main line of descent there were, especially in the Miocene, side branches now extinct, one of which (Alticamelus) was singularly giraffe-like in proportions, although not related to the giraffes, which were evolved in the Old World at the some epoch.
It is a general law in the evolution of any race of animals that at each succeeding stage in its development the progressive characters appear at an earlier period in the lifetime of the individual. The young individuals of one stage resemble the adults of the preceding stage, while the old individuals take on some of the
characters of that next succeeding. This is well illustrated in the camels, especially of the Miocene epoch; in young individuals the metapoadult camels of the Oligocene, and they are dials are always separate, as they are in all usually not completely consolidated until a comparatively advanced age. In modern camels The anterior incisors and premolars usually drop and llamas they are consolidated before birth. out in old individuals of Miocene camels; in the later stages they are minute stumps or scales which disappear early in life. W. D. MATTHEW,
American Museum of Natural History. Camelina Sativa, căm-e-li′na sa-ti'va ("gold of pleasure"), a cruciferous annual, belonging to the order Brassicacea, frequently found in cultivated fields, especially among flax, where it has long been cultivated for its seeds. which contain much oil.
Camellia, ka-měl'ya, a genus of plants belonging to the natural order Ternstræmiacea, an order which includes the tea-plant and several species of beautiful flowering shrubs, all natives of China. The name Camellia was given to this genus by Linnæus in honor of Kamel or Camellus, Moravian Camellia Jesuit. The japonica, as it grows in the woods and gardens of Japan and China, is a lofty tree of beautiful proportions, and clothed with a deep green shining foliage, with large, elegant flowers, either single or double, and of a red or pure white color. There are numerous varieties of this species in China, the greater part of which have found their way to Europe and America, while other new varieties have been produced. The double-white, double-striped, and double-waratah, the last so called from the central petals