THE HYRACES 227 



Eocene Perissodactyls. The upper molars present two obliquely 

 placed lophs connecting protocone and paracone, metacone and 

 hypocone respectively. In addition to these there is an ecto- 

 loph gathering up the two outer cones and the three primitive 

 styles. Well-marked cingula are also present fore and 

 aft. The last upper molar has no hypocone but instead 

 the metacone has subdivided to produce a pseudohypocone in 



Fig. 81. — Dentition of Hyrax (Procavia brucei var. somalica, 9.62-1). The example 

 is an adult male. Note the rodent-like upper incisors. The characters oi the cheek 

 teeth at once preclude any relationship with Artiodactyl Ungulates. 



the same manner as we have noted in herbivorous Marsupials 

 (see page 85). A curious and interesting feature of the upper 

 molars is their oblique setting in the maxilla so that a hinder 



*The cheek teeth of the species figured are brachyodont, but from this it must 

 not be inferred that the cheek teeth of all species of Hyrax are low-crowned. Pro- 

 gression to the hypsodont type has occurred in quite marked degree within the order 

 and some species of Hyrax representing a more advanced form possess quite high- 

 crowned cheek teeth. Further a hypsodont species is usually found living alongside 

 a brachyodont species in the same locality just as in Miocene and lower Pliocene 

 times species of Horses with high-crowned cheek teeth lived alongside less specialized 

 brachyodont browsing forms. 



