1.1 This classification covers both qualitative and quantitative techniques that are used commonly for the collection of phytoplankton. The particular techniques that are used during an investigation are dependent upon the study objectives. Of additional importance in the selection of a technique is the uneven distribution of organisms both temporally and spacially. This classification describes qualitative and quantitative ways of collecting phytoplankton from inland surface waters. Specifically, qualitative samplers include conical tow nets and pumps; quantitative samplers include the Clarke-Bumpus plankton sampler, Juday plankton trap, water sampling bottles, and depth-integrating samplers.