The Circadian Rhythm of Leaf Movement of Coleus blumei x C. frederici, a Short Day Plant. I. Under Constant Light Conditions.

A new instrument for the recording of leaf movement rhythm is described. Coleus blumei x C. frederici, a short day plant, exhibits a circadian rhythm of leaf movement. The period length of the free running rhythm is shortest in continuous darkness and is increased with an increase in the light intensity. The amplitude of the rhythm tends to damp in continuous bright light.