Fig. 30. Left upper dentition;
left lower dentition—
natural size.
Fig. 31. Left upper dentition
No. 3083, showing
deciduous premolars.
In the dentition, the premolar and molar teeth are covered with a thin film of cement, which is thicker on the outside of the upper teeth and on the inner side of the lower teeth. On the opposite sides of these teeth this film is so thin that it is often in part worn off.
Specimen 3083 preserves three of the deciduous premolars. Pm. 2 is simple and could readily be taken for the corresponding permanent premolar, except that it is, as are all the deciduous premolars, rooted. Deciduous premolars 3 and 4, on the other hand, have a marked inflexion on the inner side, giving them the appearance of permanent molars. The series measures 31 mm. of which the deciduous premolars occupy just half.
The mandible is deep, especially the posterior portion; has a very slender coronoid process; and a slightly rounded articular condyle, which is a little longer than wide, so that it would seem to allow a forward and backward motion of the lower jaw.
Fig. 32. Left mandible—natural size.
The vertebrae are considerably crushed, but have in each case the characteristics of the corresponding vertebra of Pachyrukhos.
Of the humerus, the head and distal ends are preserved, indicating a rather long and slender bone, very like that of Pachyrukhos. About three-fourths of the ulna is present, and it is also long and slender, with a wide articular facet for the radius, which is entirely separate from that for the humerus. Two metacarpals show the same elongation of the limb, and the two phalanges preserved indicate a small front foot.