PROFESSOR HUXLEY'S LECTURES. 



295 



Fore Foot. Hind Foot. Fore-arm. Leg. Upper Molar. Lower Molar. 



RECENT. 



EQUUS. 



o 



PLIOCENE. 



PLIOHIPPUS. 



PROTOniPPTJS ill 1 



(Hipparion). ] 



MIOCENE. 



MIOHIPPUS 



{Anchitherium). 



MESOHIPPUS. 



EOCENE. 



OBomppus. 



bJ 





