UNG-ULATA,] MAMMALIA 429 teeth, forming an uninterrupted series. The cervical vertebra resemble those of the Camels in the position of the vertebrarterial canal, but the ends of the centra are flat, and not opisthoccelous as in the allied forms. In some of the limb characters it resembles Oxen), are now the dominating members of the great Ungulate order, widespread in geographical range, rich in generic and specific variation, and numerous in individuals, f nrmirujc in ^IL.tkattA^resuiects a great contrast to such resented by the Tapirs and
- haracters by which they are
issodactyles are as follows, h not alike, the former being d. The last lower molar of ion almost invariably three- expanded posteriorly. No id lumbar vertebrae together Former may vary from twelve bird trochanter. Third and nost equally developed, and
- ened on their inner or con-
L is not symmetrical in itself, but others have been gradually becoming more specialized and more perfected in structure, and its latest modification, the Cavicorn Ruminants or Bovidse (Antelopes, Sheep, and ng Artiodactyles. A, Pig (Sws sew/a).
- C, Camel (Camelus bactrianus), XJ-
mar ; s, scaphoid; w, undfnrm ; m, mag- . ? rom Osteology of Mammalia, I together they form a figure le drawn between them. Or, ledian line of the whole foot hird and fourth digits, while ine drawn down the centre of ilar surface of the astragalus facets, one for the navicular ie. The calcaneum with an end of the fibula. Stomach complex. Colon convoluted, sed or cotyledonary. Mamma) .s and abdominal. lammals, it is only from the exist- l classification can be derived, and upon the group must be directed, 3 known that they can only be he Ungulata, however, it is quite ition, the history of the Artio- period is now well known, and aon and relations of the existing ^n^wtv, which have taken place in the type .-,..st" Icnown and most generalized manifestation have oeen tne" following : r 1. As regards the teeth. Assumption of the grinding surfaces ol the molar teeth either of a distinctly tubercular (bunodont) or of a
crescentic ridged (sclenodont) form. Modification of the latter from