PARAHIPPUS. 



93 



the metaconid than in the other known species of this genus. This type apparently represents one of the least specialized 

 species of the genus." (Osborn, 1918) (7) Crochet present on superior grinders and prominent, especially on m ]_3 , conse- 

 quently pre- and postfossettes early enclosed. 



Fig. 69. Referred specimen of Parahippus pawniensis Gidley, Princeton Mus. 12293. Jaw one-half natural size, 

 teeth natural size. 



Parahippus coloradensis Gidley 1907. 

 Plates 8.7,12. Text Fig. 70. 



Parahippus coloradensis sp. nov., Gidley, J. W. "Revision of the Miocene and Pliocene Equidte of North America," Bull. Amer. 

 Mus. Nat. Hist., Vol. XXIII, Art, XXXV, Nov. 26, 1907, p. 932, no figure. 



Horizon and locality. — Pawnee Creek, Logan County, northeastern Colorado, Pawnee Creek formation, Middle 

 Miocene. Type collected by J. W. Gidley. 



Type. — Amer. Mus. 9040. A single upper molar, m 3 . Measurements: (Gidley) m 3 a.p. .016, tr. .0205, height of 

 crown .0145. Paratypes. Amer. Mus. 9412, 8282. Two fragments of lower jaws containing teeth. 



Type figure. — Plate 8.12, text Fig. 70 of this Memoir. 



Characters. — (Gidley, 1907, p. 933) "(1) Larger than P. pawniensis, about equalling P. crenidens in size; (2) tooth 

 crown comparatively high; (3) outer walls of paracone and metacone strongly ribbed; (4) metaloph with crochet well 

 developed, the type tooth presenting two additional enamel folds; (5) the metastylid of the lower teeth well developed and 

 separated from the metaconid by a well marked groove reaching nearly to the base of the crown. (6) On the external 

 walls of the lower teeth the enamel is very rough, almost wrinkled in appearance." 



(Osborn, 1918) The type, m 3 , Amer. Mus. 9040, is quite distinctive, the crochet not being single but represented 

 by two enamel folds. One of the lower jaws selected by Gidley as a paratype, Amer. Mus. 9412, belongs to an animal 



