uperior molars.
| | | | | | |Zygapophyses.
| | | | | | | |Brain.
| | | | | | | |
Pliocene.
|1-1, 2-2
| |Digitigrade. (Plantigrade.)
| | |Grooved. (Flat.)
| | | |Interlocking. (Opposite.)
| | | | |Faceted.
| | | | | |4-tubercles, crested and cemented.
| | | | | | |Doubly involute. Singly involute.
| | | | | | | |Hemispheres larger, convoluted.
| | | | | | | |
Upper Miocene. (Loup Fork.)
|3-3, 4-4, (5-5)
| |
| | |
| | | |
| | | | |
| | | | | |
| | | | | | |
| | | | | | | |
| | | | | | | |
Middle. (John Day.)
|2-2, 3-3, 4-4
| |Digitigrade.
| | |Grooved.
| | | |Interlocking.
| | | | |Faceted. Smooth
| | | | | |4-tubercles, and crested
| | | | | | |Singly involute. Double involute.
| | | | | | | |Hemispheres larger, convoluted.
| | | | | | | |
Lower (White River.)
|3-3, 4-3
| |Digitigrade. Plantigrade.
| | |Grooved.
| | | |Interlocking.
| | | | |Smooth. Faceted.
| | | | | |4-tubercles, and crested
| | | | | | |? Singly involute.
| | | | | | | |Hemispheres small, and largeer.
| | | | | | | |
Eocene. Upper (Bridger.)
|3-3, 4-3, 4-5
| |(Digitigrade.) Plantigrade.
| | |Grooved. (Flat.)
| | | |Opposite. Interlocking.
| | | | |Smooth.
| | | | | |4-tubercles. 3-tubercles, and crested.
| | | | | | |Singly involute. Plane
| | | | | | | |Hemispheres small.
| | | | | | | |
Middle. (Wasatch.)
|4-3, 4-5, 5-5
| |Plantigrade. (Digitigrade.)
| | |Flat. (Grooved.)
| | | |Opposite. Interlocking.
| | | | |Smooth.
| | | | | |4-tubercles. 3-tubercles, a few crested.
|