360 SYNOPSIS OF THE VERTEBRATE FAUNA OF THE PUERCO SERIES. 



AMBLYPODA. 

 PANTOLAMBDA Cope. 

 Amer. Naturalist, 1882, p. 418 ; Tertiary Vertebrata, 1885, p. 601. 



Additional material belonging to the two known species of this genus, throw 

 light on points of structure hitherto unknown. 



As regards the dentition, the superior premolars are identical with those of 

 Coryphodou. 



In the anterior foot the cuneiform has the general character of that of Corypho- 

 dou. The pisiform facet is wider, thus approaching the unguiculate types of the same 

 epoch. 



In the posterior foot the cuboid of the P. cavirictus differs from that of 

 any of the Coryphodontida^ which I have seen in the greater mutual obliquity 

 of the two proximal facets. That for the astragalus is a wide concave fossa; 

 that for the calcaneum is a hook-shaped band, the convexity proximad, and 

 the longer arm, or stem, of the hook anterioi-, and the shorter posterior to 

 a ligamentous fossa. The anterior band-like facet turns transversely distally. The 

 position of the cuboid is oblique in the foot, giving the digits which arise from it a 

 divergent direction externally. The astragalus of this species closely resembles that 

 of P. latlimodon. The cctocunei'form is much like that of Coryphodou, but is not so 

 depressed, the anterior face being squai'C. The mesocunet'form has only two-thirds 

 the longitudinal depth in front. The entocuneiform is narrower transversely than in 

 Coryphodou, and approaches the form of some of the unguiculates. It indicates a 

 smaller internal digit than in Coryphodou. The above-described bones all belong to 

 one individual. 



EXPLANATION OF PLATES. 



PLATE IV. 



Hemiganus otariidens Cope, natural size. 

 Fig. 1. Part of maxillary bone displaying canine anil two premolar teeth, with ? lachrymal foramen at a; and with 



part of premaxillary bone. 

 Fig. 2. Left ramus of mandible from left side. The ? canine was found separate, and is drawn in; a, same from 



above, canine omitted. 

 Fig. 3. Parts of pariijtal and frontal bones from above ; a, temporal ridge. 



Fig. 4. Right frontal and part of i)arietal Ijone. llie sutural surface showing olfactory fossoe on inferior face. 

 Fig. 5. Left inferior ? canine tootli represented in flg. 3, from front ; ii, from behind. 

 Fig. 6. Inferior premolar tooth free from alveolus, from front ; a, from inner side ; h, from above. 

 Fig. 7. First inferior molar of right side, external view. 

 Fig. 8. Atlas, left lialf, fnun left side ; a, from behind. 

 Fig. 9. Axis from above ; a, from right side. 

 Fig. 10. Cervical vertebra without epiphyses ; a, from below. 

 Figs. 11-12. Cervical vertebra- ; a, from below. 



