Proborhyaena Ameghino

Proborhyaena Amegh., 1897, Bol. Inst. Geog. Argen., t. 18, p. 501.

The genus is founded on a large lower jaw carrying the canine and premolars 3 and 4 and roots or alveoli for the other teeth. It is the largest carnivore recorded from Patagonia, and as large as a small bear. It is not possible to place its exact relationships, for the most essential teeth are wanting, but it is certainly a distinct genus as indicated by the reduced size of premolar 4 and the plump character of the teeth.

Proborhyaena gigantea Ameghino

P. gigantea Amegh., 1897, Bol. Inst. Geog. Argen., t. 18, p. 501.

We found no specimens of this great carnivore, so I am reproducing Ameghino’s figure and measurements. The heavy canine is channeled on the sides and much worn on the posterior face. Premolar 3 is a plump tooth, its crown consisting mostly of a single median cusp, but with a small heel behind, and, strikingly enough, premolar 4 is a smaller and simpler tooth with a single cusp.

Fig. 144. Right mandible—½ natural size,
after Ameghino.

Measurements
Lower dentition,canine, antero-posterior diameter30 mm.
Lower dentition,canine, transverse diameter20 mm.
Lower dentition,premolar 1 to molar 3 145 mm.
Lower dentition,height of mandible under pm. 460 mm.

Proborhyaena antiqua Ameghino

This species is known only by a single canine 100 mm. long, of which but 15 mm. belongs to the crown. Its antero-posterior diameter is 14 mm., the transverse 12 mm. It seems to me very doubtful whether this is a valid species.