1. (1) In plants not possessing motor activity, for example, the sunflower, Helianthus annus L., the bean Phaseolus multiflorus Wild, the buckwheat Fagopyrum sagittatum Gilib, and the pumpkin Cucurbita pepo L., the presence of action potentials spreading in the acropetal and basipetal directions has been established. 2. (2) The action potentials in the plants not possessing motor activity in their characteristics are similar to the a.p. of "sensitive" plants of the Mimosa pudica and insectivore type, for example, Drosera rotundifolia, Dionaea muscipula and also the cells of algae Nitella and Chara. 3. (3) On spread of a.p. in the basipetal direction there is increase in the latent period and the rate of spread falls as compared with the a.p. spreading in the acropetal direction in the same plant. 4. (4) The a.p. in higher plants apparently in the same way as in animal tissues, may be the carrier of information from some organs to others on change in the external environment. © 1967.