The Plankton of the Illinois River. 1894-1899, with Introductory Notes upon the Hydrography of the Illinois River and Its Basin.

When the work of the Illinois Biological Station was begun in 1894. it seemed to the Director desirable to determine as far as possible the normal routine of aquatic life as a necessary basis for the detection of problems for investigationand experiment, and as an indispensable background for their adequate solution. Such an investigation demands not only the discovery and specific determination of the biological population, but involves also the study of life histories, seasonal changes, and mutual dependencies of the assembled organisms by quantitative and statistical methods, together with a study of the environment and an analysis of its factors.