196 LAND MAMMALS IN THE WESTERN HEMISPHERE 



now seem so exotic, such as the llamas, camels and horses, were 

 yet truly indigenous and were derived from a long line of 

 ancestors which dwelt in this continent, but are now scattered 

 abroad and extinct in their original home, while others were 

 migrants that for some unknown reason failed to maintain 

 themselves. Others again are everywhere extinct. 



Most surprising, perhaps, in a North American landscape, 

 is the presence of the Proboscidea, of which two very distinct 

 kinds, the fmastodons and the true elephants, are found together. 

 Over nearly the whole of the United States and southern 

 Canada, and even with sporadic occurrence in Alaska, ranged 

 the fAmerican Mastodon (f Mastodon americanus) which was 

 rare in the plains, but very abundant in the forested regions, 

 where it persisted till a very late period and was probably 

 known to the early Indians. This animal, while nearly related 

 to the true elephants, was yet quite different from them in 

 appearance, as will be immediately seen on comparing 1 and 4, 

 Fig. 113, p. 195. The most obvious external difference was the 

 comparative shortness of the legs in the fMastodon, which 

 did not exceed and seldom attained a height of 9 ft. 6 in. 

 at the shoulder ; the head also was lower and more flattened. 

 The teeth were very different from those of the elephants ; 

 the grinding teeth were much smaller and simpler, being low- 

 crowned and rooted and having three or four high, transverse,- 

 enamel-covered crests, without cement. The tusks were 

 elephant-like except that in the male there was a single small 

 tusk in the lower jaw, which cannot have been visible exter- 

 nally ; this is a remnant of an earlier stage of development, 

 when there were two large tusks in the lower as well as the 

 upper jaw. The creature was covered with long, coarse, 

 dun-coloured hair; such hair has been found with some of 

 the skeletons. 



Of true elephants, the North American Pleistocene had three 

 species. Most interesting of these is the northern or Siberian 

 fMammoth {Elephas '\primigenius) , a late immigrant from 



