200 



OSBORN: OLIGOCENE, MIOCENE, PLIOCENE EQUID.E. 



Gidley observes (1907, p. 905) that this type with its wide and compressed protoeone, deeply plicate enamel borders 

 of the fossettes, and long crown, definitely belongs to the N eohipparion group although its specific relations are some- 

 what indefinite. 



The characters pointed out by Cope apparently distinguish it from any other described species. 



Hipparion venustum Leidy 1S59. 

 Text Fig. 165. 



Hippotherium venustum, Leidy, Joseph. "Description of Vertebrate Fossils," in "Post-Pliocene Fossils of South-Carolina," by 

 Francis S. Holmes, Nos. 8, 9, 10, 1859, p. 105, PI. xvi, figs. 32-33a. Hipparion venustum, [Communicated without title], Proc. Acad. 

 Nat. Sci. Phila., Vol. VI, No. VII, 1853, p. 241, no figure, no description. 



Horizon and locality. — (Leidy, 1853, p. 241.) "2. Two superior molar teeth of a species of Hipparion, discovered 

 by Prof. Holmes, on Ashley River, South Carolina. It is the first time this genus has been found in America. For the 



33 a,. 



Fig. 165. Hipparion venustum Leidy. 33, 33a Crown and external views of type, natural size; 32 crown view of 

 paratype, twice natural size; 32a internal view of paratype, natural size. After Leidy, 1859, PI. xvi. 



species the name H. venustum was proposed." (1859) Discovered by Prof. Holmes and Capt. Bowman in the Post- 

 Pliocene beds of the Ashley river. (Osborn, 1910, pp. 471-472 x ) The principal locality is at Ashley, in a bluff about 

 thirty feet high, having at its base a Pliocene limestone composed of marine shells while the Post-Pliocene layer is a shallow 

 river formation consisting of yellow sands with bands of ferruginous clay four feet in thickness. The Ashley River fauna 

 is chiefly mid-Pleistocene. The type of H. venustum may have been washed in by the erosion of Pliocene sands and mingled 

 with true Pleistocene remains. 



Type and paratype. — (Leidy, 1859, p. 105) Type misplaced. (Type) "The larger specimen, pi. XVI, figs. 33, 33a". 

 A left upper molar with the protoeone broken away; (paratype) a right upper molar with the ectoloph broken away 

 (Figs. 32, 32a). Measurements: (Gidley, 1907, taken from Leidy's figures) type, a.p. .018, tr. .016; paratype, a.p. .0155, 

 tr. .013. 



Type figure. — Text Fig. 165 of this Memoir. 



Osborn, H. F. "The Age of Mammals in Europe, Asia and North America." 8vo. The Macmillan Co., Oct. 1910, 635 pp., 



220 text figs. 



