| Measurements | Specimen 3091 | Ameghino’s Type |
|---|---|---|
| Upper dentition, pm. 4 to m. 3 | 9. mm. | 9.5 mm. |
| Upper dentition, pm. 4, length | 2.75 mm. | |
| Upper dentition, each molar length | 2.1 mm. | |
| Upper dentition, each molar width | 2.25 mm. |
The lower jaw is slender, the incisor being relatively both smaller and slenderer than in C. arcidens; the back part of the ramus light and thin, the coronoid process being a tiny spur, and the articular condyle of small size, and on a level with the teeth.
| Measurements | Specimen 3005 | Ameghino’s Type |
|---|---|---|
| Lower dentition, pm. 4 to m. 3 | 10 mm. | 10.5 mm. |
| Lower dentition, in. 1 to pm. 4 | 6 mm. | 6.5 mm. |
| Lower dentition, pm. 4, length | 3.5 mm. | |
| Lower dentition, each molar, length | 2.5 mm. | |
| Lower dentition, each molar, width | 2 mm. | |
| Height of mandible under pm. 4 | 5 mm. | 4.8 mm. |
Fig. 122. C. plexus, left lower
premolar, molar series;
A, of young individual;
B, of old individual;
int., internal side;
ext., external side, × 4/1.
Fig. 123. C. prosus,
left upper premolar,
molar series, × 4/1.
Fig. 124. C. prosus,
premolar 4 and
molar 2, × 4/1.