Page:Popular Science Monthly Volume 45.djvu/23

Rh that every living creature has a capacity for receiving modifications of its structure from external influences; and that no species has become really extinct, but that it has passed into some other species. From Lamarck came about the same time his Researches, and a little later his Zoölogical Philosophy, which introduced a new factor into the process of evolution—the action of the animal itself in its efforts toward a development to suit new needs and he gave as his principal conclusions the following:

New wants in animals give rise to new organs.

The development of these organs is in proportion to their employment.

New developments may be transmitted to offspring.

His well-known examples to illustrate these views, such as that of successive generations of giraffes lengthening their necks by stretching them to gather high-growing foliage, and of successive generations of kangaroos lengthening and strengthening their hind legs by the necessity of keeping themselves erect while jumping, provoked laughter, but the very comicality of these illustrations aided to fasten his main conclusion into men's memories.

In both these statements, imperfect as they were, great truths were embodied—truths which were sure to grow.

Lamarck's declaration, especially that the development of organs is in ratio to their employment, and his indications of the reproduction in progeny of what is gained or lost in parents by the influence of circumstances, entered as a most effective force into the development of the evolution theory.

The next great successor in the apostolate of this idea of the universe was Geoffroy Saint-Hilaire. As early as 1795 he had begun to form a theory that species are various modifications of the same type, and this theory he developed, testing it at various stages as Nature was more and more displayed before him. It fell to his lot to bear the brunt in a struggle against heavy odds which lasted many years.

For the man who now took up the warfare, avowedly for science but unconsciously for theology, was the foremost naturalist then living—Cuvier. His scientific eminence was deserved; the highest honors of his own and other countries were given him, and he bore them worthily. An Imperial Councilor under Napoleon; President of the Council of Public Instruction and Chancellor of the University under the restored Bourbons; Grand Officer of the Legion of Honor, a Peer of France, Minister of the Interior, and President of the Council of State under Louis Philippe, he was eminent in all these capacities, and yet the dignity given by such high administrative positions was as nothing compared to his leadership in natural science. Science throughout