ORIGINAL COMMUNICATIONS. 



I. — On the Periodical Opening and Closing of Flowers. 

 By Karl Fritzsch. 



(Translated and abridged from the German.) 



HPHE greater portion of the work before us, which appeared 

 originally in the Transactions* of the Bohemian Society of 

 Natural History, and which contains an account of a series of 

 observations extending through many years, on those plants 

 whose corolla opens and shuts periodically, is occupied with long 

 lists of the plants, which were under examination, and voluminous 

 complicated tables of the results obtained. It would obviously 

 be impossible for us to reproduce these at length ; we think, 

 however, that such an abstract may be given as may be perfectly 

 intelligible, and may afford our readers some definite notions of the 

 conclusions at which the author has taken so much pains to arrive. 

 It is well known to every observer of what passes around him 

 in nature, that plants exhibit day by day certain periodic 

 phenomena analogous to those of sleep in animals. Either the 

 leaves alter their position so as to exhibit a totally different 

 appearance, or the flowers close more or less partially ; either 

 phenomenon taking place within certain fixed limits of time and 

 circumstance. It is to the former of these cases that our author 

 has directed his attention, as, in his opinion, more strictly allied to 

 the periodic rest which is so essential to the sustenance of animal 

 life in health and vigour. He shall, however, speak for himself. 

 " The intention of the observations now recorded is not to 

 point out what phenomena accompany sleep in plants, or to 

 explain how this function of vegetable life is effected, tbough I do 

 not see why the periodic opening and shutting of flowers should 



* Abhandlungen der Eon. bohm Gesdlschaft der Wissenschaften, V. Folge, 

 7. Band. 



Besultate mehrj'dhrige Beobachlungen iiber jene Pflanzen deren Blumen- 

 kronen sicli t'dglich jieriodisch offnen wad Schliessen von Earl Fritzsch. 4to 

 Prag. 1851, pp. 164 incl. sched. 17. tab. 1. 



VOL. VIU. B 



