THE POTATO, 165 



It is one of those plants, the introduction of which 

 into a favourable climate will enable a country to 

 double its population without materially trenching 

 on their other means of subsistence. 



The maize and the potato are striking examples 

 of the effects produced on plants by culture and ac- 

 climization. Both are natives of the tropics, and 

 both are now grown successfully in high northern 

 latitudes; while in their native warm climates the 

 product of both is of an inferior quality compared 

 with that within a few degrees of the utmost nor- 

 thern limit of their growth ; examples of which may 

 be seen in the corn of the Southern States and of 

 the West Indies, and in the potatoes of the South 

 American plains. Last year a quantity of the ori- 

 ginal root was brought from Venezuela to London, 

 and carefully planted. The product was small and 

 of inferior quality, more resembling ground-nuts 

 than potatoes, or rather approaching the first year's 

 growth of roots produced from the seeds of the po- 

 tato apple. 



In the cultivation of the potato, the root or tuber 

 is alone used for seed, as the plants from these are 

 far more vigorous and productive than those from 

 the true seed, or such as are grown from the blos- 

 soms. For producing new varieties, however, re- 

 course is had to the apples, the seed of which, planted 

 in beds, will produce roots, and from these new va- 

 rieties may be obtained at pleasure. It is in this 

 way that most of the best modern sorts have been 

 produced. To attempt to enumerate all the varie- 

 ties known would be a hopeless, not to say useless 

 task, as more than 150 are enumerated in the 'I'rans- 

 actions of the Highland Society, many of which are 

 only distinguished by such nice shades of difi'erence 

 as to be wholly overlooked by the common observer. 

 In this country the number of varieties is scarcely 

 less, though many of the kinds designated belong to 

 the same variety. Colours may be considered as 



