THE MASTODON 203 
Neither do we at present know just how many 
species of mastodons there may have been in 
the Western Hemisphere, for most of them are 
_ known from scattered teeth, single jaws, and 
_ odd bones, so that we cannot tell just what dif- 
ferences may be due to sex or individual varia- 
tion. It is certain, however, that several dis- 
tinct kinds, or species, have inhabited various 
_ parts of North America, while remains of others 
occur in South America. The mastodon, how- 
ever, the one most recent in point of time, and 
the best known because its remains are scat- 
tered far and wide over pretty much the length 
and breadth of the United States, and are 
found also In southern and western Canada, 
is the well-named Mastodon americanus,* and 
unless otherwise specified this alone will be 
meant when the name mastodon is used. In 
some localities the mastodon seems to have 
abounded, but between the Hudson and Con- 
necticut Rivers indications of its former pres- 
thinks may be the long sought ancestor of the elephant family, 
which includes the mammoth and mastodon. 
* This has also been called giganteus and ohioticus, but the 
name americanus claims priority, and should therefore be used. 
