11 



These facts being known, that nature required to 

 be refreshed in the seed, it was necessary that there 

 should be some principle discovered concerning it. 



" In all things," says M. Poiteau, " it is necessary 

 to have recourse to science, which is composed of 

 reasonings deduced from particular facts and w hence 

 we deduce what is called a principle." 



The following remarks concerning M. Van Mons, 

 are gathered from " Theorie Van Mons, ou Notice 

 Historique sur a moyens qu'emploie M. Van Mons 

 pour obtenir d'excellent fruit de semis ; par A. Poi- 

 teau" — and from conversations with M. Emilien de 

 Wael, a friend of both named distinguished gentle- 

 men. The " Notice Historique" has been published 

 in translation by the former President of the Society. 



M. Van Mons turned his attention to the discovery 

 of the causes of variation in fruits and flowers. He 

 commenced his experiments at the early age of fif- 

 teen years in his father's garden at Brussels, with the 

 seeds of roses and shrubs, and proceeded in the 

 planting of successive generations, with a view to 

 observe the changes and variations. Afterwards, he 

 began wdth the seeds and stones of fruits. From his 

 repeated sowings of annual flowers and perennial 

 shrubs which bore fruit or perfected their seeds in a 

 short time and by his accurate observations upon the 

 results developed, and by his already extended know- 

 ledge of the experience of others he arrived at this 

 conclusion concerning varieties or variation. 



" That so long as plants remain in their natural sit- 

 uations, they do not vary sensibly and their seeds 

 always produce the same — but changing their cli- 



