cliffs, slopes and water courses, as we now distinguish the cotyledons, stem, buds, leaves, flowers and fruit of a rapidly-maturing annual that produces all these forms in appropriate order and position in the brief course of a single summer.
The time is ripe for the introduction of these ideas. The spirit of evolution has. been breathed by the students of the generation now mature all through their growing years and its application to all lines of study is demanded. It is true that the acceptance of inorganic as well as of organic evolution is often implied rather than outspoken; yet evolution. is favorably regarded, as is proved by the eagerness with which even school boards and school teachers, conservatives among conservatives, hail the appearance of books in which the new spirit of geography is revealed. In the last years of the century, the school books most widely used in this country have made great advance in the explanatory treatment of land forms. Tarr's Physical Geographies and Russell's monographic volumes on the 'Lakes,' 'Glaciers,' 'Volcanoes' and 'Rivers' of North America, all presenting land forms in an explanatory rather than an empirical manner, have been warmly welcomed in this country. Penck's 'Morphologie der Erdoberfläche' (1894), although largely concerned with the historical development of the subject, presents all forms as the result of process. De Lapparent's 'Leçons de géographie physique' (1886) treats land forms generically; and a second edition of the book is called for soon after the first. 'Earth Sculpture,' by James Geikie (1899), and Marr's 'Scientific Study of Scenery' (1900), carry modern ideas to British readers. There can be little doubt that the books of the coming century will extend the habit of explanation even further than it has yet reached.
This review of the advance of the century in the study of land forms, the habitations of all the higher forms of life, might have been concerned wholly with the concrete results of exploration, as was implied in an earlier paragraph. Travels in the Far East of the Old World, or in the Far West of the New, have yielded fact enough to fill volumes. But such a view of the century has been here replaced by another; not because the first is unimportant, for it is absolutely essential, but because the second includes the first and goes beyond it. Not the facts alone, but the principles that the facts exemplify, demand our attention. These principles, founded upon a multitude of observations, are the greater contribution of the closing to the opening century in the study of the Forms of the Land.