Seeks clarification of statements on sleep movements on p. 29 of WFPP’s work [Die periodischen Bewegungen der Blattorgane (1875)].

In response to CD’s query, discusses sleep movements of plants. Recommends papers on subject.

Thanks for Movement in plants.

Describes work [on Pflanzenphysiologie, 2 vols. (1881)].

Will send 2d vol. [of his Pflanzenphysiologie (1881)].

CD has occasionally misinterpreted him in Movement in plants; by "after-working" (Nachwirkung) he means "after-working of preceding movements", not of the irritating cause [light].

It is impossible to trace the direct connections between stimuli and responses in plant movements. Disagrees with much of Julius von Wiesner [Die Bewegungsvermögen der Pflanzen (1881)]. Disagrees with CD on induced movements and circumnutation.