PRIMEVAL MAN 207 



always preyed so largely on horses, the differ- 

 ences are almost exclusively in color and in 

 features of purely external anatomy. From the 

 skull and skeleton it is not possible to deter- 

 mine with certainty the lion from the tiger, 

 and both come very close to the big spotted 

 cats; while the skulls of the horse, the ass, 

 and the common zebra are with difficulty to be 

 discriminated except by size — although the 

 skull of the big northernmost African zebra is 

 totally distinct. 



In consequence, when we speak of extinct 

 horses it is often impossible to guarantee that 

 they were not asses or zebras; and when we 

 speak of the great extinct cats of Europe and 

 North America as lions, we know that it is 

 possible that in life they may have looked more 

 hke tigers. Therefore it must be understood 

 that I use the words horse and lion as terms of 

 convenience and in a broad sense so as to avoid 

 circumlocution. I use them in exactly the way 

 in which '* elephant" is always used to include 

 the two totally distinct species now living in 

 India and Africa. By "lion" I mean any one 

 of the big extinct cats, true cats, which in their 

 cranial and skeletal characters are almost or 

 quite identical with living lions and tigers and 

 closely related to living jaguars. By "horse" 



