ON the North American Continent, between the arctic circle and the 42nd parallel of latitude, we meet with signs of ice-action on a scale as grand if not grander than in Europe; and there also the excess of cold appears to have been first felt, at the close of the tertiary, and to have continued throughout a large portion of the post-pliocene period.

The general absence of organic remains in the North American glacial formation, makes it as difficult as in Europe, to determine what mammalia lived on the continent at the time of the most intense refrigeration, or when extensive areas were becoming strewed over with glacial drift and erratic blocks, but it is certain that a large proboscidean now extinct, the Mastodon giganteus Cuv., together with many other quadrupeds, some of them now living and others extinct, played a conspicuous part in the post-glacial era. By its frequency as a fossil species, this pachyderm represents the European Elephas primigenius, although the latter also occurs fossil in the United States and Canada, and abounds, as I learn from Sir John Eichardson, in latitudes farther north than those to which the mastodon has been traced.

In the state of New York, the mastodon is not unfrequently met with in bogs and lacustrine deposits formed in hollows in the drift, and therefore, in a geological position, much resembling that of recent peat and shell-marl in the British Isles, Denmark, or the Valley of the Somme, as before described. Sometimes entire skeletons have been discovered within a few feet of the surface, in peaty earth at the bottom of small ponds, which the agriculturists had drained.