This report is based in large part upon a personal examination of the fresh water and marine biological stations of Europe, made in the summers of 1908 and 1909. Its purpose is to put in convenient form for reference an account of the history, organization, equipment, and work of the various stations of Europe, and to indicate their relations to research and to education of advanced and elementary or popular characters. Special attention has been given to the economic or applied scientific phases of their activities in the firm belief that biological stations and their methods of attack upon biological problems are destined not only to add greatly, and, in a unique way, to the advance of knowledge but are also of prime economic importance. Following a letter of transmittal and a preface, the following chapters are included: (1) The functions of biological stations; (2) Italy; (3) France and Monaco; (4) Great Britain; (5) Germany; (6) Austria-Hungary; (7) Scandinavia; and (8) Other European Countries. A bibliography and index are included. (Contains 55 plates and 48 figures.) [Best copy available has been provided.]