ORDINAL TYPES OF MOLARS: HYRACOIDKA 



LSD 



Chalicotheres have more probably been derived from Lower Eocene 

 Titanotheres. 



SPEC! A L R HFERENCE. 



Osborn, H. F., "The Ancylopoda, Chalicotherium, and Artionyx," A IDC/: Xtin-<ili*t, 

 Feb., 1898, pp. 118-133. [The discussion about Art/on//. < is based upon a font n<>\\ 

 known to appertain to the Oreodont Artiodactyl Agriochcerus.] 



HYKACOIDEA. 



The Hyraces, including many existing African and West Asiatic 

 species, also the fossil forms Pliohyrax Osborn, Saghatherium Andrews, 

 M<'</lohyrax Andrews, exhibit strong evidences of derivation from a buno- 



Fig. 185. Milk dentition of a Hyracoid (Scnjhatln rium antiqaum}), from the Upper Eocene 

 of Egypt, with buno-lopho-selenodont cheek teeth, xl. 



pr. 



Fig. 186. Upi>< i- fiijuri , Hiim.i- x/ir incus, upper clieek teeth, external view. x-g-. Lowa- X 1 "' 1 ' 

 A, Hiii-n.i- capensis, third upper molar, unworn, x ". B, II. si/riacus, third lower molar, worn. 



lopho-selenodont ancestral type. The superior molar teeth (Figs. 1S.~>. 

 18G), consist of two short, transverse crests, the proto- and metalophs, and 

 an elongate external crest, the ectoloph. The latter has been eomp;ireil 

 with that of the rhinoceros, but actually resembles that of tbe 



