HISTORY OF THE HORSE 57 



foot. Some scientists believe that the still more ancient 

 ancestors possessed five toes on each foot. The teeth of 

 these very early animals Vi^ere short-crowned and covered 

 with low, rounded cusps of enamel somewhat similar to 

 those of swine, and differing widely from the long- 

 crowned, rather complicated, molars of the horse. 



Distribution of prehistoric horse. — In the latter part of 

 the Tertiary and in the early Quarternary periods, wild 

 species of the horse were to be found on every continent 

 except Australia. Remains of the horse have been found 

 in all parts of the United States, in Alaska, in Mexico, 

 in Central and South America, as well as in Europe, Asia 

 and Africa. The first discovery of these fossil horses in 

 the United States was made by Mitchell, in 1826, near the 

 Navesink Highlands in New Jersey. About the middle 

 of the century Leidy made similar discoveries in Ne- 

 braska. Following these came other discoveries, until the 

 wide distribution of the horse in America became well 

 established. Specially rich localities are on the Niobrara 

 River in Nebraska, in central Oregon, in the phosphate 

 mines near Charleston, South Carolina, in central 

 Florida, in southern Texas, Arizona, Kansas, Louisiana 

 and many other states. In fact, the fossil remains of the 

 horse are so abundant in deposits of rivers and lakes of 

 the Pleistocene epoch that the formation in the western 

 Linited States has received the name of Equus Beds. 



Evolution of the horse. — The prehistoric development 

 of the horse has been thoroughly investigated by the 

 American Museum of Natural History. Twelve stages 

 have been recognized in the evolution of the horse family 

 from the early Tertiary period to the present ; each stage 

 being characteristic of its peculiar geological time, with 

 the horse becoming more and more developed toward the 

 present-day. type, as the periods become more and more 

 recent. A few of these stages have been found in various 

 parts of the world, but by far the most complete and best- 

 known series comes from the Tertiary Badlands of our 



