ARTIFICIAL SELECTION. 393 



tions, we do not allow it time to fix itself defin- 

 itely; and that an interruption produces in the next 

 generation a plant of so much worse quality as has 

 been the length of this time. 



That to delay the flowering, produced the most 

 beautiful flowers. 



That fertility increases with repeated generations. 



That the plant, after being regenerated a certain 

 number of times, loses in vigor what it gains in 

 form ; that is to say, that, in laying aside its rude 

 and wild nature to take one more delicate and 

 domesticated, it becomes more sensitive to the 

 severities of the seasons. 



At the age of twenty-two years Van Mons com- 

 menced to apply his theory, resulting from his 

 experiments upon annual plants, to fruit trees. The 

 first generation of Van Mons departed very much 

 from its type, producing a crop, after ten or twenty 

 years, of very small and inferior fruit. This he 

 sowed immediately, and obtained the second genera- 

 tion of less wild appearance, but yet not suitable 

 for table use. The seeds of this were again sown, 

 and so on to five generations, when he obtained 

 trees which bore in five to ten years. 



Dr. Van Mons started upon the hypothesis that 

 all our cultivated varieties of fruits were ameliora- 

 tions, by cultivation and successive generation, of 

 the wild sorts ; and yet may not there be a vast 

 difl"erence in the specific nature of the wild and 



