XI 



PLANTS THAT TELL THE TIME OF DAY ; PLANTS THAT 

 KEEP A DIARY 



PLANTS can actually tell the time! 

 Certain plants open and close at definite 

 hours of the day with such regularity that they 

 can be, and have been, relied upon as timepieces. 

 Unknowing persons have claimed that this is "due 

 to the changes in temperature," but there is evident 

 in plant life an understanding of periods of time 

 which can be laid to no such cause as temperature. 

 We are forced to believe that they have a knowledge 

 of the hours of the day. There are some plants 

 the white or red water-lily, the proliferous pink, 

 and the purple sandwort which regularly open 

 and close not only at definite hours but at definite 

 minutes in those hours I 



The idea of plants telling the time of day is not 

 new. The Swedish botanist, Linnaeus, realising 

 this remarkable power of the plant, built himself a 

 floral clock which should, by the hours and minutes 

 of the opening and closing of his plants, indicate 

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