Page:EB1911 - Volume 02.djvu/742

This page has been proofread, but needs to be validated.

approximated to that of a carnivore. The upper molars, which may be either selenodont or buno-selenodont, carry five cusps each, instead of the four characteristic of all the preceding groups; and they are all very low-crowned, so as to expose the whole of the valleys between the cusps. In Anoplotherium, some of the species of which were larger than tapirs, there were either two or three toes, the latter number being almost unique among the Artiodactyla. Allied genera are Diplobune and Dacrytherium.

The Dichobunidae include the genus Dichobune, of which the species were small animals with buno-selenodont molars. Xiphodon and Dichodon represent another type with cutting premolars and selenodont molars; while Caenotherium and Plesiomeryx form yet another branch, with resemblances to the ruminants. The most interesting genera are however, the Upper Oligocene and Lower Miocene Gelocus and Prodremotherium, which have perfectly selenodont teeth, and the third and fourth metacarpal and metatarsal bones respectively fused into an imperfect cannon-bone, with the reduction of the lateral metacarpals and metatarsals to mere remnants of their upper and lower extremities. While Gelocus exhibits a marked approximation to the Tragulidae, Prodremotherium comes nearer to the Cervidae, of which it not improbably indicates the ancestral type. The Dichobunidae may be regarded as occupying a position analogous to that of the Homacodontidae in the Tylopoda, and like the latter, are probably the direct descendants of Condylarthra.

1911 Britannica - Anoplotherium commune.png
Fig. 2.—Restoration of Anoplotherium commune.

The last section of the Artiodactyla is that of the Suina, represented at the present day by the pigs (Suidae), and the hippopotamuses (Hippopotamidae), and in past times by the Anthracotheriidae, in which may probably be Suina. included the Elotheriidae. In the existing members of the group the cheek-teeth approximate to the bunodont type, although showing signs of being degenerate modifications of the selenodont modification. There is at least one pair of upper incisors, while the full series of 44 teeth may be present. The metacarpals and metatarsals are generally distinct (fig. 1 A), and never fuse into a complete cannon-bone; and the navicular and cuboid bones of the tarsus are separate. The odontoid process of the second vertebra is pig-like: and the tibia and fibula and radius and ulna are severally distinct. The stomach is simple or somewhat complex, and the placenta diffused. The Suidae include the Old World pigs (Suinae) and the American peccaries (Dicotylinae), and are characterized by the snout terminating in a fleshy disk-like expansion, in the midst of which are perforated the nostrils; while the toes are enclosed in sharp hoofs, of which the lateral ones do not touch the ground. There is a caecum. The Dicotylinae differ from the Suinae in that the upper canines are directed downwards (instead of curving upwards) and have sharp cutting-edges, while the toes are four in front and three behind (instead of four on each foot), and the stomach is complex instead of simple. In the Old World a large number of fossil forms are known, of which the earliest is the Egyptian Eocene Geniohyus. Originally the family was an Old World type, but in the Miocene it gained access into North America, where the earliest form is Bothriolabis, an ancestral peccary showing signs of affinity with the European Miocene genus Palaeochoerus. (See Swine and Peccary.)

The Hippopotamidae are an exclusively Old World group, in which the muzzle is broad and rounded and quite unlike that of the Suidae, while the crowns of the cheek-teeth form a distinctly trefoil pattern, when partially worn, which is only foreshadowed in those of the latter. The short and broad teeth terminate in four subequal toes, protected by short rounded hoofs, and all reaching the ground. The hinder end of the lower jaw is provided with a deep descending flange. Both incisors and canines are devoid of roots and grow throughout life, the canines, and in the typical species one pair of lower incisors, growing to an immense size. The stomach is complex; but there is no caecum. Although now exclusively African, the family (of which all the representatives may be included in the single genus Hippopotamus, with several subgeneric groups) is represented in the Pliocene of Europe and the Lower Pliocene of northern India. Its place of origin cannot yet be determined.

The extinct Anthracotheriidae were evidently nearly allied to the Hippopotamidae, of which they are in all probability the ancestral stock. They agree, for instance, with that family in the presence of a descending flange at the hinder end of each side of the lower jaw; but their dentition is of a more generalized type, comprising the full series of 44 teeth, among which the incisors and canines are of normal form, but specially enlarged, and developing roots in the usual manner. The molars are partially selenodont in the typical genus Anthracotherium, with five cusps, or columns, on the crowns of those of the upper jaw, which are nearly square. The genus has a very wide distribution, extending from Europe through Asia to North America, and occurring in strata which are of Oligocene and Miocene age. In Ancodon (Hyopotamus) the cusps on the molars are taller, so that the dentition is more decidedly selenodont; the distribution of this genus includes not only Europe, Asia and North Africa, but also Egypt where it occurs in Upper Eocene beds in company with the European genus Rhagatherium, which is nearer Anthracotherium. On the other hand, in Merycopotamus, of the Lower Pliocene of India and Burma, the upper molars have lost the fifth intermediate cusp of Ancodon; and thus, although highly selenodont, might be easily modified, by a kind of retrograde development, into the trefoil-columned molars of Hippopotamus. In the above genera, so far as is known, the feet were four-toed, although with the lateral digits relatively small; but in Elotherium (or Entelodon), from the Lower Miocene of Europe and the Oligocene of North America, the two lateral digits in each foot had disappeared. This is the more remarkable seeing that Elotherium may be regarded as a kind of bunodont Anthracotherium. It shows the characteristic hippopotamus-flange to the lower jaw, but has also a large descending process from the jugal bone of the zygomatic arch of the skull. Finally, we have in the Pliocene of India the genus Tetraconodon, remarkable for the enormous size attained by the bluntly conical premolars; as the molars are purely bunodont, this genus seems to be a late and specialized survivor of a primitive type.  (R. L.*) 

ARTISAN, or Artizan, a mechanic; a handicraftsman in distinction to an artist. The English word (from Late Lat. artitianus, instructed in arts) at one time meant “artist,” but has been restricted to signify the operative workman only.

ARTOIS, an ancient province of the north of France, corresponding to the present department of Pas de Calais, with the exclusion of the arrondissements of Boulogne and Montreuil, which belonged to Picardy. It is a rich and well-watered country, producing abundance of grain and hops, and yielding excellent pasture for cattle. The capital of the province was Arras, and the other important places were Saint-Omer, Béthune, Aire, Hesdin, Bapaume, Lens, Lillers, Saint-Pol and Saint-Venant. The name Artois (still more corrupted in “Arras”) is derived from the Atrebates, who possessed the district in the time of Caesar. From the 9th to the 12th century Artois belonged to the counts of Flanders. It was bestowed in 1180 on Philip Augustus of France by Philip of Alsace, as the dowry of his niece Isabella of Hainaut. At her death in 1190, Baldwin IX., count of Flanders (d. 1206), and then his son-in-law, Ferrand (Ferdinand) of Portugal, count of Flanders, disputed the possession of the country with the king of France, Ferrand being in the coalition which was overthrown by Philip Augustus at Bouvines (1214). In 1237 Artois, which was raised to a countship the following year, was conferred as an appanage by Saint Louis on his brother