PARAHIPPUS. 



89 



Fig. (jo. Parahippus amis Marsh, Am. Mus. 14182, referred specimen. (1) Ulna and radius, outer and front views. 

 Ulnar shaft moderately slender, slightly coossified in middle portion although this skeleton is of an old individual. (2) 

 Outer view of humerus. (3) Tibia, front and outer views. All figures one-half natural size. 



Parahippus brevidens Marsh 1874. 

 Plate 8.11. Text Fig. 66. 



Anchippus brevidens, sp. nov., Marsh, 0. C. "Notice of New Equine Mammals from the Tertiary Formation," A met: Jour. Sci. 

 and Arts, (3), Vol. VII, No. 39, March, 1874, pp. 254-255, no figure. 



Horizon and locality. — (Marsh) "Pliocene of Oregon." Probably Maseall formation of the John Day series, Cotton- 

 wood Creek, Middle Miocene. Name of collector not given. 



Type. — Yale Mus. 11274. Three upper molar teeth, m 2-3 of the left side, ?m 1 or p 4 of the left side. Measure- 

 ments: (Marsh) nr a. p. .017"), tr. .022; m 3 a. p. .017, tr. .0125; height of unworn crown of m 3 .015. 



Type figure. — Plate 8.1 1, text Fig. 60 of this Memoir. 



Characters. — (Marsh, 1874, Osborn, 1918) (1) Antero-median lobe [protoconule] forwardly placed, hence its worn 

 surface is not in the same line with that of the antero-internal lobe [protocone]; (2) posterior crescentoid tubercle [meta- 

 conule] isolated, wearing into an ear-shaped lobe, inclosing a pit [postfossette] with cement; (3) molar crowns unusually 



