Page:A Treatise on Geology, volume 1.djvu/115

 CH. V.

Some of these ossiferous deposits are of historical date, the others of greater but various antiquity, so as to permit the construction of the following table of the successive races of mammalia.

The preceding table adds another to the proofs already given of the extreme analogy between the tertiary and modern periods of geology. We find in the tertiary formations remains of nearly all the great natural orders and groups into which systematists have divided mammalia: in most instances, however, the species, and often the genera, differ; yet it must be borne in mind that these differences are not greater than now obtain between the animals of the analogous climates of America, Africa, and India. Admitting for the moment, what must hereafter be discussed, the distinctness of the alluvial, diluvial, and tertiary deposits, we may observe that in the diluvial reliquiæ of mammalia, most of the genera, and some of the species, are the same or extremely like to living tribes: while in the modern accumulations it is rare to find an extinct species, though some specimens of the great Elk of Ireland are probably of this date.

But there is one remarkable exception to this analogy of the tertiary and diluvial fauna, with our present races of mammalia; no remains of Man have yet been found in any of these deposits—no trace of his works; and it is yet entirely doubtful whether the race of man existed at all during what are called the diluvial periods. The same exception almost extends to the order of quadrumana, which, in their animal nature and organisation, most