“…Continuously illuminating plants with light of different wavelengths has been shown to influence the rhythms in Phaseolus [28], Neurospora [3,35], Arena [23,32] and Bryophyllum [31]. If Phaseolus plants are transferred from a greenhouse to continuous illumina-tion, it is found that the period of the rhythm of leaf movement is modified by red and far-red light but not by other wavelengths.…”