27 



PHALANGES. 



M. 



Length of first phalanx , ; . . .022 



Width of first phalanx .012 



Length of second phalanx -013 



Width of second phalanx -oio 



Length of ungual phalanx -005 



Width of ungual phalanx .QIO 



PAL^EOSYOPS, Leidy. 



Hayden's Geological Survey of Montana, 1871. Proceedings Academy Natural 

 Sciences, Philadelphia, 1871, p. 118. Limnohyus. Marsh, American Jour- 

 nal Science and Arts, 1872, p. 124. 



Generic characters. The dentition is full, I. 3, C. i, Pm. 4, 

 M. 3 ; the same in lower jaw. The internal cones of the supe- 

 rior molars isolated from the crescentoid crests. One inner 

 tubercle on the last three premolars. One internal cone on 

 the last superior molar. In lower jaw, true molars with four 

 acute tubercles alternating in pairs and connected by oblique 

 crests. The last molar adds a fifth posterior tubercle. The 

 last premolar lacks the posterior inner tubercle. The canines 

 are in continuity with the incisors. 



A broad, triangular forehead. A wide zygoma. Long, 

 projecting nasals. Large temporal fossae. High sagittal 

 crest. Prominent and nearly vertical occiput. 



PAL^OSYOPS MAJOR, Leidy. 



Survey of Wyoming, 1871, p. 359. Limnohyus robustus. Marsh, American 

 Journal Science and Arts, 1872, p. 124. 



Specific characters. Sagittal crest short and thick. Tem- 

 poral fossae not very deep. Frontals diverge rapidly. Occi- 

 pital condyles wide and low ; the same is true of the fora- 

 men magnum. Meatus auditorius high and deep. Glenoid 

 cavity shallow ; no internal process. As compared with P. 

 Paludosus, post-glenoid process not so much compressed. 

 Occipital region comparatively higher and not so concave. 

 The occipital condyles are more prominent. The zygomas 

 are lighter. Head larger than Paludosus, perhaps not so large 

 as Vallidens. 



Description from (i) a head, complete, but distorted, with 

 complete dentition, upper and lower. (2) A head somewhat 



