r and perhaps not accidental
coincidence that so many of the early tertiary mammals known to us are
large herbivora, such as would be included in the Hebrew word
_bhemah_; and that in the book of Job the hippopotamus is called
_behemoth_, the plural form being apparently used to denote that this
animal is the chief of the creatures known under the general term
_bhemah_, while geology informs us that the prevailing order of
mammals in the older tertiary period was that of the ungulates, and
that many of the extinct creatures of this group are very closely
allied to the hippopotamus. Behemoth thus figures in the book of Job,
not only as at the time a marked illustration of creative power, but
to our farther knowledge also as a singular remnant of an extinct
gigantic race. It is at least curious that while in the fifth day
great reptiles like those of the secondary rocks form the burden of
the work, in the sixth we have a term which so directly reminds us of
those gigantic pachyderms which figure so largely in the tertiary
period. Large carnivora also occur in the tertiary formations, and
there are some forms of reptile life, as, for example, the serpents,
which first appear in the tertiary.

I may refer to any popular text-book of geology in evidence of the
exact conformity of this to the progress of mammalian life, as we now
know it in detail from the study of the successive tertiary deposits.
The following short summary from Dana, though written several years
ago, still expresses the main features of the case:

"The quadrupeds did not all come forth together. Large and powerful
herbivorous species first take possession of the earth, with only a
few small carnivora. These pass away. Other herbivora with a larger
proportion of carnivora next appear. These also are exterminated; and
so with others. Then the carnivora appear in vast numbers and power,
and the herbivora also abound. Moreover these races attain a magnitude
and number far surpassing all that now exist, as much so indeed, on
all the continents, North and South America, Europe, Asia, Africa, and
Australia, as the old mastodon, twenty feet long and nine feet high,
exceeds the modern buffalo. Such, according to geology, was the age of
mammals, when the brute species existed in their greatest
magnificence, and brutal ferocity had free play; when the dens of
bears and hyenas, prowling tigers and lions far larger than any now
existing, covered Britain and Europe. M