CLASSIFICATION OF VERTEBRATA 47 



Bibodon. Oligocene, South America. 

 Protapirus. Eocene of Europe. 

 \/ Tapirus. Miocene of Europe and India, recent in ( Ciitial 

 and South America, Malacca, Sumatra, and Borneo. 

 w Equidae. Lower molars quad ri tubercular or with tw<> 

 transverse ridges curved into two half- moons, leading to W 

 pattern. Toes |, | or \. Since the Eocene. 



Hyracotherium. | T . Lower Eocene, England. 

 Eolnppos. J ^' Lower Eocene, Wyoming. 



Palaeotherium.] Eocene to Miocene, Europe and U.S.A. 

 Mesohippos. VToes !}. Lower Miocene, Dakota. 

 Aiichitherium. J Upper Miocene, of Europe = Miohippos, 



U.S.A. 

 Hipparion. Toes -§-. tipper Miocene of Europe, Asia 



and U.S.A. 

 Protohippos. Toes |. Pliocene, U.S.A. 

 Pliohippos. Toes \. Pliocene, U.S.A. 

 Hippidion. Toes |. Plistocene, South America. 

 Equus. Toes \. Since Miocene in India, since Pliocene 

 *~m Europe. During the Plistocene cosmopolitan, 

 excluding Australian region. 

 Jikinocerotidae. Lower molars with two transverse half- 

 moons. Toes -"J-- Since the Eocene. 



Hyrachius. Upper Eocene, Wyoming. 



Hyracodon. Lower Miocene, Nebraska. 



Aceratherium. Oligocene, France ; Miocene, Europe, 



India, North America. 

 Diceratherium. Miocene, Oregon. 

 Ehinoceros. Since the Miocene in Asia, Plistocene 

 of Asia and Europe. Eecent in the palaeotropical 

 regions including Sumatra, Java, Borneo, excluding 

 Madagascar. 

 Titanotheridae. Eocene and Miocene of Europe and North 

 America. 



Palaeosyops. Eocene, U.S.A. 



Titanotherium (Brontotherium). Lower Miocene, 



U.S.A. 

 Leptodon. Upper Miocene, SE. Europe. 

 8. Sub-order ANCYLOPODA, Cope. Plantigrade ; terminal 



