LECT. IV.] THE ROOT. TUBERS. 157 



formed independent altogether of the nutriment 

 obtained from the tuber bearing the plant, is evi- 

 dent ; for, the first tubers of the plant raised from 

 seed are formed altogether from the nutriment 

 obtained from the soil. It should, however, be re- 

 collected, that the plant raised from seed differs 

 from that evolved from the gem on a tuber ; the 

 former being an entire new being, a renewal of the 

 species, the latter a mere continuation of the in- 

 dividual from which it springs. It may be sup- 

 posed, that although the new tubers be formed 

 from the nutriment obtained from the soil, yet 

 that the contents of the old tuber are intended 

 chiefly for perfecting the flower and the seed *, in 

 the same manner as the saccharine matter depo- 

 sited in the caudexes of the Turnip and Carrot ; 

 but, admitting this supposition, it is not the less 

 true that this nutriment may be diverted to the use 

 of the new tubers ; for those on the Potatoe plant, 

 are both enlarged and multiplied by nipping off 

 the flowers, to prevent the formation of the seed. 

 From whatever source the nutriment is obtained, 

 the healthy state of the leaf is absolutely requisite 

 to perfect the tuber ; for, the partial destruction of 



* This supposition certainly obtains some support from the 

 fact, that Potatoes produced on plants raised from seed do not 

 flower in the second or third year ; the tubers apparently re- 

 quiring a greater magnitude and higher degree of perfection 

 before they can form the flower. 



