Irritability of Plants

Abstract

IN your issue for April 19 (vol. xlix. p. 586) there is a short notice of a paper by Prof. Pfeffer on the “Irritability of Plants.” In it you say: “Pfeffer instances the remarkable researches of Hegler on the effect of mechanical traction on growth stems, which when stretched by a weight, gain mechanical strength through the development of the mechanical tissues, which follows as a response to the pull to which they are subjected.”