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facts have been correlated with it, that I introduce a classification of constructional forms. Some such classification is essential, but it is difficult to establish satisfactorily, because of the endless variety of structures found in nature. At present in the elementary course I recognize only plains and plateaus of horizontal strata; mountains of disordered strata, with many minor subdivisions; and in a subordinate way, volcanic cones and flows, and glacial hills and moraines. Like the more difficult orders of plants in an elementary course on Botany, mountains must be treated briefly in an elementary course on Physical Geography, and their fuller treatment left for more advanced study. After the various kinds of constructional forms are treated, it is advisable to review the features of rivers, with their divides, lakes, waterfalls, flood plains, and deltas; and in this connection a week or two may be given to the forms assumed by the waste of the land on the way to the sea. The distribution of different kinds of forms should be briefly given with their classification.
When thus developed, Physical Geography may worthily claim the dignity of a University study. Its subject matter is of importance in itself, as well as in its relations to geology, zoölogy and botany, or to history and economics. Its methods are of value in training various mental faculties: observation, description, generalization; imagination, comparison, discrimination; these are all cultivated to a high degree in the student who successfully utilizes the opportunities of the course.
Two other aspects of the subject may be briefly considered.
Areal geography.—The study of the fauna and flora of a region or of a continent requires the examination of all of its animals and plants according to some acceptable scheme of classification. The study of the areal geology of a region involves the examination of its formations in their order of local occurrence, but also with regard to the general, world-wide scheme of geological classification. In the same way, the study of the areal geography of a country or of the world calls for the recognition of the parts that compose the whole, of their location and area, and of