OF NATURAL HISTORY. 257 



penfible parts of the experiment, therefore, be tried, nothing can be 

 concluded in favour of the fexual fyftem. 



5. That flowers growing from the fame root, fruits upon the 

 fame tree, or raifed from feeds of the fame individual plant, often 

 vary in colour, fize, figure, and texture. Thefe varieties are appa- 

 rent to the moft fuperficial obfervers ; but they can never, with any 

 degree of propriety, be afcribed to the influence of fex. The caufes 

 of fuch variations are rather to be looked for in the expofure of the 

 plants with regard to light and air, the nature of the foil, the mode 

 of culture, accidental injuries from dews, from eleflrical fire, from 

 the poifon or wounds of infe£ts, and from the abforpcion of mineral 

 folutions. In a word, if we are to hope for an explanation of thefe, 

 and other minute changes in the appearances of plants, recourfe 

 muft be had to chemical and philofophical principles, and not to an 

 hypothetical commerce of fexes. 



The difcourfe was concluded with the following fentlment : — 

 But I aim not at complete refutation; for experiments are ftill to be 

 made. 1 only wifti to render the fexual commerce of plants fu- 

 fplcious, that the minds of men may be freed from the fetters of a 

 fyftem, which has, perhaps, too long received the general aflTent of 

 Europe; and that the oeconomy of the vegetable kingdom may 

 again be open to impartial invefliigation. 



To remove the poflibihty of male influence being conveyed by 

 means of the wind, or of infedls, about ten or twelve years ago, I 

 thought, if a female plant could ripen her feeds within doors during 

 the winter, the experiment would infallibly determine the contro- 

 verfy. With this view, I confined a female lychnis, which is a na- 

 tive plant of this country, and gave her fuch a degree of heat as 

 made her produce flowers three months before any male flowers of 

 I K k f the 



