126 



ELEPHANTS 



only three on the others. Other ancestral elephants 

 had quite ordinary-looking grinders, with only two or 

 three irregular ridges or broad tubercles. Both the 

 Indian and African elephant have hairless, rough, very 

 hard, wrinkled skins. But the newborn young are 

 covered with hair, and some Indian elephants living in cold, 

 mountainous regions appear to retain a certain amount of 



B 



FIG. 13. The crowns of three "grinders" or molars of elephants 

 compared. A is that of an extinct mastodon with four transverse 

 ridges ; B is that of the African elephant with nine ridges in use 

 and ground flat ; c is that of the mammoth with sixteen narrow 

 ridges in use the rest, some eight in number, are at the left hand 

 of the figure and not yet in use. 



hair through life. The mammoth (which agreed with the 

 Indian elephant in the number of ridges on its grinders 

 and in other points) lived in quite cold, sub-Arctic condi- 

 tions, at a time when glaciers completely covered Scandi- 

 navia and the north of our islands as well as most of 



