7 ON THE ART OF MAKING WINS. 



the methods to be followed in naturalizing exo- 

 tic plants in general *, The observations of al 

 gardeners have long since shewn, that a tender exo- 

 tic, rarely, if ever, becomes habituated to a cli- 

 mate, if it be propagated by layers, grafts, or cut- 

 tings , since the new plant is always'perfectly iden- 

 tkal in all its habits and properties with the pa- 

 rent, of which indeed it forms a part. But a ma- 

 terial change in the constitution of plants is pro- 

 duced by sowing the seeds, and the seedlings are 

 invariably more hardy than the plant from which 

 they were derived. I quoted in that paper some 

 observations made by Sir Joseph Banks, on the 

 naturalization of Zizama aquatica, and related an 

 instance still more remarkable of a similar effect 

 produced on Canna indica, a native of the' West 

 India islands, by successive sowing of the seeds in 

 Guernsey. From these two remarkable facts, and 

 perfect examples of success, as well as from innu- 

 merable more imperfect trials, it seems clearly es- 

 tablished, that any plant may be naturalized to 

 this climate, provided its seeds can be made to 

 grow in succession. This, however theoretically 

 true, is obviously attended with much practical 

 trouble, in consequence of the difficulty of descend- 

 ing equally, and for a given length of time, 

 through a given range of temperature ; a difficulty 

 which would, in fact, in most cases^ be insuperable. 

 But no such obstacle prevents the further naturali- 



* Published in vol. i. p. 284. of the Memoirs of the Society* 



