Of these three we found only the last.
Asteromys prospicuus Ameghino
A. prospicuus Amegh. loc. cit. above.
Fig. 128. Right upper premolar
4—molar 3, × 4/1.
Fig. 129. Left lower
molar 2, × 4/1.
The species is rare, only three specimens turning up in our collections. The upper molars are as described in the generic discussion, but premolar 4 is simpler than the molars, the posterior lamina being small and without any sort of furrow. In the upper molars the anterior lamina is larger than the posterior, and the anterior furrow wider than the posterior. The following measurements, with the figures, indicate the character of the species.
| Upper dentition, | premolar 4 to molar 3 | 8.75 mm. |
| Upper dentition, | premolar 4, length | 2. mm. |
| Upper dentition, | each molar, length | 2.3 mm. |
| Upper dentition, | each molar, width | 2. mm. |
| Lower dentition, | molar 2, length | 2.75 mm. |
| Lower dentition, | molar 2, width | 1.75 mm. |