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AMBLYPODA
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AMBLYPODA , a suborder of See also:primitive ungulate mammals, taking its name from the See also:short and stumpy feet, which were furnished with five toes each, and supported massive See also:pillar-like limbs. The See also:brain,-cavity was extremely small, and insignificant in comparison to the bodily bulk, which was equal to that of the largest rhinoceroses. These animals are, in fact, descendants of the small ancestral ungulates which have retained all the primitive characters of the latter accompanied by a huge increase in bodily See also:size. They are confined to the See also:Eocene See also:period, and occur both in See also:North See also:America and See also:Europe. The cheek See also:teeth are short crowned (brachyodont), with the tubercles more or less completely fused into transverse ridges, or See also:cross-crests (lophodont type); and the See also:total number of teeth is in one See also:case the typical 44, but in another is reduced below this. The vertebrae of the See also:neck unite by nearly See also:flat surfaces, the humerus has lost the foramen, or perforation, at the See also:lower end, and the third trochanter to the femur may also be wanting. In the fore-See also:limb the upper and lower See also:series of carpal bones scarcely alternate, but in the See also:hind-See also:foot the astragalus overlaps the cuboid, while the fibula, which is quite distinct from the See also:tibia(as isthe See also:radius from the ulna in the fore-limb), articulates with both astragalus and calcaneum. The most generalized type is Coryphadon, representing the See also:family Coryphodontidae, from the lower Eocene of Europe and North America, in which there were 44 teeth, and no See also:horn-like excrescences on the See also:long See also:skull, while the femur had a third trochanter. The canines are somewhat elongated, and were followed by a short See also:gap in each See also:jaw, and the cheek-teeth were adapted for succulent See also:food. The length of the See also:body reached about 6 ft. in some cases. In the See also:middle Eocene formations of North America occurs the more specialized Uintatherium (or Dinoceras), typifying the family Uintatheriidae, which also contains See also:species sometimes Restored See also:skeleton of Uintathcrium (Dinoceras) mirabile. (After O. C. See also:Marsh.) separated as Tinoceras. Uintatheres were huge creatures, with long narrow skulls, of which the elongated facial portion carried three pairs of bony horn-cores, probably covered with short horns in See also:life, the hind-pair being much the largest. The dental See also:formula is i. 1-, c. p. s -, m. I; the upper canines being long sabre-like weapons, protected by a descending flange on each See also:side of the front of the lower jaw. In the basal Eocene,of North America the Amblypoda were represented by extremely primitive, five-toed; small ungulates such as Periptychus and Pantolambda, each of these typifying a family. The full typical series of 44 teeth was See also:developed in each, but whereas in the Periptychidae the upper molars were bunodont and tritubercular, in the Pantolambdidae they have assumed a selenodont structure. Creodont characters (see See also:CREODoNTA) are displayed in the skeleton. See also H. F. See also:Osborn, " See also:Evolution of the Amblypoda," See also:Bull. Amer. • See also:Mus. vol. x. p. 169. (R. Additional information and CommentsThere are no comments yet for this article.
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