EVOLUTION OF THE HORSE 



39 



every tooth, and every part of the skeleton had been changed 

 by slow degrees during unmeasured periods of past time. 



Moreover, with this knowledge as their basis, they knew 

 they had in hand a key which would help unlock the mys- 

 tery of all change in all animals, both ancient and modern. 



Head 



Fore Foot 



HindFoot 



Teeth 



Erotohippus 



Hyracotherium 

 (EohippusJ 



'■ ^ OneToe 

 Splints of 



2nd and 4th 

 'digits 



OneToe 



Splints of 



2nd and 4th 



digits 



ThreeToes 

 Side toes 

 I i not touching 

 the ground 



ThreeToes 



Side toes 



not touching 



the ground 



Long- 

 Crowned, 

 Cement- 

 covered 



t ThreeToes 

 Side toes 

 touching the 

 ground; 



Splint of 5th digit 



ThreeToes 



Side toes 



touching the 



ground 



Four Toes 



Short- 

 Crowned, 

 without 

 Cement 



FourToes 

 Splint of 

 Jet digit 



ThreeToes 

 Splint of 

 Sth digit 



Drawing of Skulls, Feet, and Teeth of Prehistoric Horses, 

 grouped for Comparison 



They show the development of the horse by evolution. (Reproduced, by permission, 

 from " Origin and History of the Hdfse," by H. F. Osbom) 



As might be supposed, it takes two sets of scientists to 

 make out the truth about buried bones. 



i. There is the geologist. He studies the earth itself, 

 knows which parts of it were formed first, which later, and 

 by knowing just where the bones came from, he tells us which 



