Recent Advances in the Study of Vascular Anatomy. I. Vascular Anatomy and the Reproductive Structures

IT is perhaps unfortunate that the names applied to the great divisions of botanical investigation shift in their meaning from time to time, but it is inevitable. The content of a subject shifts with the men who put content into it. The morphology of to-day is not the morphology of half a century ago, either in its content or motive; or rather there are several conceptions of morphology existing side by side, some as an inheritance, and others as acquired characters. The older conception of morphology, presented, for example, in the model textbooks of Asa Gray, is one thing; and that introduced by the work of Hofmeister, which very slowly made its way into this country, is a very different hing. This more, recent morphology adds to the old knowledge of structures the relation of these structures in a scheme of phylogeny. Its importance lies not so much in the fact that it solves the perennial problem of phylogeny, as in the fact that it calls for the selection and comparison of structures tllrloughout he plant kingdom. It takes the enormous debris of material that has accumulated and sifts it, passing over the trivial, emphasizing the important, and building up the body of knowledge into a structure that has some form. As knowledge' advances, the trivial of yesterday may become the important to-day, and vice versa; but the building of a structure, upon any plan, is work of a higher order