HISTORY OF THE PROBOSCIDEA 427 



follows: 3^, 6-9, 9-12, 9-15, 14^16, 18-27. The skeleton 

 was more like that of the Indian Elephant than of the other 

 species, though with a number of small differences in the skull. 

 In size, the fMammoth was comparatively small, standing 

 about nine feet six inches at the shoulders. In North America 

 its range was from Alaska southeastward across the continent 

 to New England. 



The second species, the fColumbian Elephant (E. ^columbi 

 Fig. 114, p. 198), was eighteen inches or more taller than the 

 fMammoth and rivalled the largest existing elephants in 

 stature ; its huge tusks curved first downward and then upward 

 and inward, their tips crossing when full-grown. The grinding 

 teeth had fewer and thicker enamel plates than those of the 

 fMammoth. The range of the fColumbian Elephant over- 

 lapped the southern border of that of the fMammoth, but was, 

 on the whole, much more southern ; it crossed the continent 

 from ocean to ocean and covered nearly the whole of the United 

 States, extending down to the southern end of the Mexican 

 plateau. The two species were very closely related and in some 

 cases are so intergraded that it is difficult to distinguish them ; 

 the fMammoth was an undoubted immigrant and the fColum- 

 bian Elephant was probably a local North American variant of 

 it, adapted to a somewhat warmer climate. Nothing is known 

 of the skin or hair in the latter animal, but, from the fact that 

 it was not a tropical species and was exposed to very cold 

 winters, it may be inferred that it had a hairy covering of 

 some sort. 



The third species of elephant (E. ^imperator) was older 

 geologically than the others, as it was more characteristic of 

 the lower Pleistocene and uppermost Pliocene; its range 

 coincided with the western half of the region covered by E. 

 '\columbi, extending far into Mexico, but not occurring east 

 of the Mississippi River. It was an enormous creature, the 

 largest of known elephants, with an estimated height of thirteen 

 and a half feet at the shoulder (Osborn). The grinding teeth 



