OF THE POTATOE PLANT. 15 



the potatoe alone with a small piece of tuber attached, a 

 shoot from that eye, or a bud from the haulm, which will 

 grow either by layering or from a cutting. 



(54.) In the cultivation of the potatoe, man has espe- 

 cially in view the selection of those varieties the tubers of 

 which are most developed. The tuber is the part employed 

 for the purposes of man, and therefore he selects those va- 

 rieties which will give the largest produce, and which are 

 richest in starch. 



(55.) These individual peculiarities which attach to the 

 kinds or varieties of potatoes, are to the plant what idio- 

 syncrasy is to the human being. Every man has certain 

 constitutional peculiarities : some persons even die from 

 the bleeding following trifling operations, others are poi- 

 soned by minute doses of mercury ; some are short, others 

 are tall, and in fact every one has something sufficient to 

 distinguish him from his neighbors. 



(56.) Every kind of plant evinces these peculiarities 

 where every seedling is an individual. If we walk along 

 a country road in spring, we find every thorn putting forth 

 its buds at a different time ; and the varieties are so marked 

 in the horse-chestnut tree, that some individual plant will 

 be many days in leaf before its neighbor has expanded its 

 buds. 



(57.) Our present potatoe must not be confounded with 

 the potatoe in use before 1600. The potatoe then spoken 

 of is the Convolvulus batata, or sweet potatoe, a convolvu- 

 laceous plant now in use in the West Indies. 



(58.) It is this potatoe to which allusion is made in 

 Shakspeare (" Let the sky rain potatoes ") in the " Merry 

 Wives of Windsor," act v., Scene 5 ; the word " pota- 



