OF BUDS. 139 



Pyrus Mains, Engl Bot. t. 179; and I 

 cannot but assent to Mr. Knight's opinion, 

 that each individual thus propagated has only 

 a determinate existence, in some cases longer, 

 in others shorter; from which cause many 

 valuable varieties of apples and pears, known 

 in former times, are now worn out, and others 

 are dwindling away before our eyes. New 

 Varieties of Cape Geraniums, raised from seed 

 in our greenhouses, are of still shorter dura- 

 tion, and can be preserved by cuttings for a 

 few successive seasons only ; yet several of 

 these stand in our botanic works, with all the 

 importance of real species. Gardeners know 

 how many of the most hardy perennial herbs 

 require to be frequently renewed from seed 

 to exist in full vigour; and though others ap- 

 pear, to our confined experience, unlimited in 

 that respect, we have many reasons to be- 

 lieve they arc not so. Propagation by seeds 

 is therefore the only true reproduction of 

 plants, by which each species remains di- 

 stinct, and all variations are effaced ; for 

 though new varieties may arise among a 

 great number of seedling plants, it does not 

 appear that such varieties owe their pecu- 



