was itself the result of evolution, for one can not ask the means to an end until the end is seen or known. Up to the time of Linnæus there was little general interest in zoölogy and botany, but after he had placed in systematic order such facts as were known to the scientific world of his day, others began to find all about them additional facts which had been theretofore unrecorded, and so interest in Nature began its steady rise toward the high position which it holds to-day. So long as the great majority of forms were unknown or undescribed, the only question was concerning what existed, and naturalists everywhere were busy with these facts of the existence of species; but as the records became more complete and the knowledge of natural phenomena wider spread, of course the tendency would naturally be toward inquiry as to how these innumerable forms arose. Even as early as the latter part of the eighteenth century some of the deepest thinkers were turning this question over in their minds, although they did not appreciate its great importance or its bearing on the acquisition of knowledge. Darwin himself began his career as a gatherer of facts, but his active mind soon saw the inadequacy of the doctrine of special creations, and demanded something more in accordance with the facts. The history of the development in his own mind of the famous theory to which his name is attached is a most fascinating story, but it is not necessary to enter into any details here. Suffice it to say that he became thoroughly convinced in his own mind, and actually convinced the whole scientific world, even including his most bitter opponents, that the question of the hour was not one of which species was which, nor to what family it belonged when identified, but “How did species arise?” From that day to this the whole trend of scientific study has been toward the solution of that problem, and an enormous amount of investigation by biologists, far and near, has thrown much light on its intricacies, although, when we consider all phases of the subject, including the difficulties of heredity, we feel that we have hardly made more than a beginning.
This change of position in the subject-matter of scientific research has brought about a most remarkable and far-reaching change in method, which is universally recognized as vastly superior to the old. But it seems also to have brought about an equally radical change in the spirit of investigation; and instead of the reverent work of an Owen, an Agassiz, or a Lyell, who believed they were studying the creations of an Omnipotent God, Maker and Father of all, we have the enthusiastic, energetic, all-embracing investigations and theories of a Haeckel, a Huxley, or a Spencer, who certainly can not be accused of holding any pronounced religious beliefs whatever. There can be no doubt that this change too was a very natural one; for as long as men felt
