“In answer to these questions I will venture to submit the following reflections: The fossil remains of vegetables hitherto dug up in so many parts of the globe, are, on a close inspection, found to belong to two different states of our planet. The parts of vegetables and their impressions, found in mountains, of a colaceous and schistous, or even sometimes of a calcareous nature, are chiefly of plants now existing between the tropics, which would neither have grown in the latitudes in which they are dug up, nor have been carried and deposited there by any of the acting forces under the present constitution of nature. The formation indeed of the very mountains in which they are buried, and the nature and position of the materials which compose them, are such as we cannot account for by any actions and re-actions which in the actual state of things take place on the surface of the earth. We must necessarily recur to that period in the history of our planet, when the surface of the ocean was at least so much above its present level as to cover even the summits of those secondary mountains which contain the remains of tropical plants. The changes which these vegetables have suffered in their substance is almost total; they commonly retain only the external configuration of what they were. Such is the state in which they are found in England by Lhwyd; in France by Jussicu; and in the Netherlands by Burtin; not to mention instances in more distant countries. Some of the impressions or remains of plants found in soils of this nature which were, by the more ancient and enlightened oryctologists, supposed to belong to plants actually growing in temperate and cold climates, seem, on accurate investigation, to have been part of exotic vegetables. In fact, whether we suppose them to have grown near the spot where they are found, or to have been carried thither from different parts by the force of an impelling flood, it is equally difficult to conceive how organized beings, which, in order to live, require such a vast difference in temperature and seasons, could live on the same spot, or how their remains could (from climates so widely distant) be brought together in the place by one common dislocating cause. To this ancient order of fossil vegetables belong whatever retains a vegetable shape found in or near coalmines, and (to judge from the places where they have been found) the greater part of the agatized woods. But from the species and state of the trees which are the subject of this memoir, and from the situation and nature of the soil in which they are found, it seems very clear that they do not belong to the primeval order of vegetable ruins.