摘要：A new instrument to quantify the zooplankton grazing on phytoplankton and the phytoplankton growth is described. This instrument consists of two cylindrical chambers and a mechanical system for shutting, by a messenger both the chambers simultaneously. With this instrument the grazing may be evaluated by counting the algal cells at the beginning and the end of the experiment as well as by the radioisotope technique. This instrument combines the advantages of others used to the same aim by other authors; e.g. Gliwicz (1968), Haney (1971), Hart & Christmas (1984). As an example, the results of two experiments are reported.
