Peat investigations are based on the viewpoint that morphological features of an area of peat reflect its origin and development, the variety in arrangement of layers, and the various properties of different kinds of peat and muck. With this in view the author discusses 3 aspects of his work (1) stratigraphic features of peatland; (2) structural characteristics of peat and muck, and (3) particular characteristics in the structure of some Alaskan peat materials. Photographs supplement the descriptions, chiefly with reference to primary types of peat.