386 History of the Sexual Theory. [BOOK in. 



published them, together with some similar works of Koelreuter, 

 at Prague in 1797 under the title, 'R. J. Camerarii Opuscula 

 Botanici Argumenti.' This book, apparently little known, will 

 be my principal authority for the following remarks. The 

 short preliminary communications are printed without alteration 

 from the ninth and tenth year of the second, and from the fifth 

 and sixth year of the third decury of the Ephemerides of the 

 Leopoldina; the letter to Valentin, which will be noticed 

 again further on, together with an abstract of the same and an 

 answer of Valentin, are given according to Gmelin's edition of 

 1749. 



Camerarius had observed, that a female mulberry-tree once 

 bore fruit, though no male tree (amentaceis floribus) was in 

 its neighbourhood, but that the berries contained only abor- 

 tive and empty seeds, which he compared to the addled eggs 

 of a bird. His attention was roused, and he made his first 

 experiment on another dioecious plant, Mercurialis annua ; he 

 took in the end of May two female specimens of the wild 

 plant (they were usually called male, but he knew them to be 

 the female) and set them in pots apart from others. The 

 plants throve, the fruit was abundant and filled out, but when 

 half ripe they began to dry up, and not one produced perfect 

 seeds ; his communication on this subject is dated December 

 28, 1691. In the third decury of the Ephemerides, year 5, he 

 relates that in a sowing of spinach he had found monoecious 

 as well as dioecious plants, as Ray had observed in Urtica 

 romana, and he himself again in three other species. The dis- 

 regard of this fact was afterwards the cause of erroneous in- 

 terpretation of the experiments and of doubt about sexuality. 



and finally, in 1695, First Professor of the University, in succession to his 

 father, Elias Rudolph Camerarius. He was afterwards succeeded by his 

 son Alexander, one of ten children. There is an article on Camerarius in 

 the ' Biographic Universelle,' from the pen of Du Petit-Thouars. His 

 works on other subjects, as well as those on the question of sexuality in 

 plants, are distinguished by ingenious conception and lucid exposition. 



