Of Dr. Hooker, whom I have often cited in this chapter, Mr. Darwin has spoken in the Introduction to his 'Origin of Species, as one 'who had, for fif… - Charles Lyell

Cesalpino, a celebrated botanist, conceived that fossil shells had been left on the land by the sea, and had concreted into stone during the consolidation the soil; and in the following year (1597), Simeone Majoli went still farther, and coinciding for the most part with views of Cesalpino, suggested that the shells and matter of the Veronese, and other districts, might have cast up, upon the land, by volcanic explosions, like those gave rise, in 1538, to Monte Nuovo, near Puzzuoli.- This hint was the first imperfect attempt to connect the position fossil shells with the agency of volcanoes, a system more fully developed by Hooke, [Antonio] Lazzaro Moro, Hutton, and other writers. Two years afterwards, Imperati advocated the animal origin of fossilized shells, yet admitted that stones could vegetate by force of 'an internal principle,' and, as evidence of this, he referred to the teeth of fish, and spines of echini found petrified.

Leibnitz, the great mathematician, published his 'Protogaea' in 1680. He imagined this planet to have been originally a burning luminous mass, and that ever since its creation it has been undergoing gradual refrigeration. Nearly all the matter of the earth was at first encompassed by fire. When the outer crust had at length cooled down sufficiently to allow the vapors to be condensed, they fell and formed a universal ocean, investing the globe, and covering the loftiest mountains. Further consolidation produced rents, vacuities, and subterranean caverns, and the ocean, rushing in to fill them, was gradually lowered. The principal feature of this theory, the gradual diminution of the original heat, and of an ancient universal ocean, were adopted by Buffon and De Luc, and entered under different modifications, into a great number of succeeding systems.

Lamarck, after having first studied botany with success, had then turned his attention to conchology, and soon became aware that in the newer (or tertiary) strata of the earth's crust there were a multitude of fossil species of shells... He also observed that other shells were so nearly allied to living forms, that it was difficult not to suspect that they had been connected by a common bond of descent. He therefore proposed that the element of time should enter into the definition of a species, and that it should run thus: 'A species consists of individuals all resembling each other, and reproducing their like by generation, so long as the surrounding conditions do not undergo changes sufficient to cause their habits, characters, and forms to vary. He came at last to the conclusion, that none of the animals and plants now existing were primordial creations, but were all derived from pre-existing forms, which, after they may have gone on for indefinite ages reproducing their like, had, at length, by the influence of alterations in climate and in the animate world, been made to vary gradually, and adapt themselves to new circumstances, some of them deviating, in the course of ages, so far from their original type as to have claims to be regarded as new species.