De Maillet, the first attempt in modern times to bring together the evidence in favor of the Evolution of Life, with the causes sufficient to produce it, is to be found in the writings of Lamarck—the Philosophical Zoology (1809), and the History of Animals without Vertebrae (1815). Lamarck was Professor of Zoology at the Garden of Plants, in Paris, and, far from being a mere dreamer, was an eminent naturalist, as every one admits, whatever may be thought of his speculations. Many of these speculations, however, are regarded by distinguished living Biologists as profound truths, such as, that "there is no distinct vital principle," that "life is only a physical phenomenon," that "the nervous system produces ideas, and all the acts of the intelligence," etc.
In the works just alluded to, Lamarck, basing his views on the structure of plants and animals, and their petrified remains, develops the theory of there having been a progress in the organic world from the simpler forms of life to the higher; that all organisms in the lapse of ages had descended from pre-existing ones. As causes of the transmutation of species, Lamarck held that the force of the will, as exhibited in the use and disuse of organs, exercised great influence in modifying the structure of animals; he attached also great importance to the facts of inheritance. While it is admitted that there is a great deal in the writings of Lamarck that cannot be maintained, still, he must be considered as the first who attempted to develop in detail the theory of the Evolution of Life, and one of its most distinguished advocates. Noticing that Lamarck held that the Monkey descent of Man, previously advocated by Monboddo, was a necessary consequence of his theory, we pass on to Geoffrey St.-Hilaire, the distinguished and constant opponent of Cuvier in the discussions on the Origin of Species at the Garden of Plants. Although for a long time St.-Hilaire had thought as Lamarck, it was not till 1828
