346 UNGULATA. 



rudimentary and do not touch the ground (fig. 624). In 

 the living Peccaries {Dicotyles), again, the fore-feet are the 

 same as in Suh ; hut the hind-feet become unsymmetrical 

 by tlie reduction of the fifth digit to its metatarsal. In the 

 Miocene Elothcrium the digits on each foot are reduced to 

 the third and fourth, the second and fifth being present only 



Fig. 642. — Grinding surface of tlie molar and pnftmolar teeth of a Peccary 

 {Dicotyles labiatus). (After Giebel.) 



in the form of rudimentary " splint-bones," concealed beneath 

 the skin. Lastly, in many of the older Tertiary Suicla there 

 appear to have been four functionally-useful toes to all the 

 feet, the second and fifth digits reaching the ground as well 

 as the third and fourth. 



The genus Sus itself appears to have commenced in the 

 Miocene Tertiary, with the Sus Lockarti and S. cJiceroides of 

 the Middle Miocene, and the S. antiquus, S. major, and >S'. 

 cryriianthius of the Upper Miocene. The last mentioned of 

 these is a very large Wild Boar which occurs in the Tertiary 

 deposits of Pikermi in Greece. In the Upper Pliocene of 

 Prance we meet with the Sus arvernensis, and the living 

 Sus scrofa appears for the first time in the Post-Pliocene 

 deposits of Europe. No species of the genus Sus have as 

 yet been detected in North America. The genera Pala'o- 

 chcerus and Hyotheriuvi of the European Miocene resemble 

 Sus proper in most respects, but the tubercles of the molar 

 teeth are more distinctly circumscribed. The Miocene 

 Amphichcerus resembled tlie two genera just mentioned, and 

 differed from Sus in not having the last molar excessively 

 developed, and in the simpler type of the tubercles of the 

 molar teeth ; but it possessed extremely long canines, which 

 were directed downwards in the upper jaw. Below the 

 Miocene no Pigs of the modern type have been as yet traced 

 in the European area. 



The I'eccary {Dicotyles), as already mentioned, is the 



