PLIOHIPPUS. 



153 



(10) The type an old individual with teeth so much worn as to obliterate distinctive characters. (17) Lateral meta- 

 podials broken. (18) As compared with Equus the preorbital region is short; (19) angle of the jaw of great depth, 

 and molars proportionately short-crowned and curved; (20) characteristic facial pits, or fossa', including (?) a deep 

 lachrymal pit. 



Fig. 121. Pliohippus pemix Marsh, Yale Mus. 13007. (Left upper) Left humerus of the type, anterior and inferior 

 views; (middle and right) left ulna and radius of the type, anterior and external views; (left lower) distal view of tibia of 

 the type. All figures one-half natural size. 



(Matthew, 1913) The species Pliohippus pemix is doubtfully separable from the type of Pliohippus supremus Leidy. 

 Troxell 1 has recently (1916) discovered the skeleton of Pliohippus luUianus, not far removed from P. pemix, which 

 verifies Marsh's definition that Pliohippus differs from other equine in the absence of lateral digits. 



1 Troxell, Edward L. "An Early Pliocene One-Toed Horse, Pliohippus IvMianus, sp. nov." The Am. Jour, of Science, (4), 

 Vol. XLII, No. 250, Oct. 1916, pp. 335-348, figs. 1-7. 



