Since CORTI (1774) observed for the first time a streaming in plant cells, a history oJ mnre than 180 years has already elapsed in the study of proto plasmic streaming. Durling this period of time, many experiments have been conducted and various discussions have been made nn prntoplasmic streaming, each of them within the limits of the knowledge and techniques of its own times and mnre or less under the influence of the ideas that pre vailed then. With such a long history of research, in spite of all the interest and efforts that have been devoted to it by many, the mechani'sm of this in...