ELEPHANTS, RHINOCEROSES, AND HORSES 259 



Modern zoologists divide the great Ungulate group the 

 Hoofed Mammals into the following principal divisions or 

 sub-orders, most of which are extinct. There is a hypothetical 

 parent-group called by von Zittel " Protungulata" which, seem- 

 ingly, gave rise to three divergent sub-orders the Condylarthra, 

 the hypothetical Platyarthra^ and the Prohyracoidea, or ancestors 

 of that diminished group of which the little hyrax of Africa is 

 the only living representative. From the Condylarthra sprang 

 the Odd-toed and the Even-toed Ungulates (Perissodactyla and 

 Art'wdactyla), which are the dominant Ungulates of to-day. It 

 is possible, also, that from the Condylarthra arose a very 

 aberrant group of Ungulates, in which the hoofs (as in the 

 camel and in other early types of Artiodactyle) had retained, 

 or reverted to, a claw-like growth. These are known as 

 the Ancylopoda. From the Platyarthra arose the Amblypoda * 

 and the Proboscidea (elephants). Lastly, from the Prohyra- 

 coidea (a divergent group of early Ungulates no doubt akin in 

 origin to the stocks which gave rise to the Primates and the 

 Rodents) were developed the extinct sub-orders of the 'Toxodontia 

 and I'ypotheria (South America), together with the Hyracoidea^ 

 which at the present day are represented by the hyraxes of 

 Africa and Syria. 2 The only sub-orders of Ungulates which 

 are now or have been in the not-far-distant past represented 

 in the British Islands are the elephants (Proboscidea]^ the 

 Odd-toed (Perissodactyla] and the Even-toed (Artiodactyla) 

 Ungulates. 



1 A remarkable group of early Ungulates, offering faint resemblances 

 in their structure, but not in their dentition, to the elephants. They are 

 celebrated, amongst other points, for their extravagant development of the 

 canine teeth into long tusks, and for the huge, bony, horn-bearing processes 

 of their skulls, which were evolved in the American forms. A relatively 

 early type of Amblypod was Coryphodon, with great canine tusks, and, in the 

 lower jaw, large proclivous incisors. A Coryphodon once dwelt in Camber- 

 well, among other places, its remains having been found there at the bottom 

 of a well. 



2 Extinct members of the Hyrax group are found in Europe and Asia 

 Minor. 



