Morren found in several species of Oxalis that the leaves and their foot-stalks moved, especially after exposure to a hot sun, when they were gently and repeatedly touched, or when the plant was shaken.
Morren-ek zenbait Oxalis espezietan aurkitu zuen hostoak eta haien txortenak mugitu egiten zirela, batez ere eguzki berotan egon ondoren, poliki eta behin eta berriz ukitzean, edo landarea astintzean.