Marvellous as are those cosmical revolutions belonging to the period of emergence of the northern zone of America from the great Arctic Ocean, when we look on each completed whole the process appears to have been characterised by no abnormal violence. Slowly through long centuries the ocean shallowed. The deep-sea organisms of a former generation were overlaid by the littoral shells of a newer marine life, and then the tidal waves retreated from the emerging sea-beach; until now we seek far down in the gulf of the St. Lawrence and on the coast of Labrador for the living descendants of species gathered from the post-pleiocene drift. Thus the closing epoch of geology in the New World, as in the Old, is brought into contact with that in which its archæology begins; and we look upon the North American continent as at length prepared for the presence of man. Such records are here noted among the disclosures of the great valley of the St. Lawrence, which drains well-nigh half a continent; for it is in the valleys by which the present drainage of historic areas takes place, that not only such deposits of recent shells and fossil relics of existing fauna occur, but also that the most extensive remains of the extinct mammalia are disclosed, in association with objects serving to link them with those of modern eras. In formations of this character have been found, in the lower valley of the Mississippi, the _Elephas primigenius_, the _Mastodon Ohioticus_, the _Megalonyx_, _Megalodon_, _Ereptodon_, and the _Equus curvidens_, or extinct American horse: with many other traces of an unfamiliar fauna, and also a flora, contemporaneous with those gigantic mammifers, but which also include both marine and terrestrial representatives of existing species. Corresponding in its great geographical outlines very nearly to its present condition, the American continent must have presented in nearly all other characteristics a striking contrast to its modern aspect, clothed though it seems to us in primeval forests, and scarcely modified by the presence of man. In the post-pleiocene formations of South Carolina, exposed along the bed of the Ashley River, remains of the megatherium, megalodon, and other gigantic extinct mammals occur, not only associated with existing species peculiar to the American continent, but also apparently with others, hitherto believed to have been domesticated and introduced for the first time by modern European colonists. But more interesting for our present purpose, as possibly indicating the contemporaneous existence of some of those strange mammals with man, are notices of remains of human art in the same formation. Professor Holmes, in exhibiting a collection of fossils from the post-pleiocene of South Carolina before the Academy of Natural Sciences of Philadelphia, remarked: “Dr. Klipstein, who resides near Charleston, in digging a ditch for the purpose of reclaiming a large