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this position also holds true ; for, if we produce 

 a delay in the period at which annual plants 

 flower, with many we succeed in converting 

 them into biennials. Wheat will furnish us with 

 a familiar example. In its natural state it is 

 but an annual plant, pushing from the seed in 

 spring, flowering in summer, ripening its grain 

 in autumn, and dying with the approach of win- 

 ter, the whole period of its existence scarcely 

 exceeding six months. 



From the mode in which it is generally culti- 

 vated, however, its life is often protracted to 

 twelve, sometimes to thirteen months, being fre- 

 quently sown in September and not reaped until 

 the October of the following year. Numerous 

 other individuals are improved in their natural 

 qualities by cultivation. All the varieties of the 

 apple, for example, owe their origin to the sour 

 arid unpalatable crab, which no one would now 

 recognize in the flavour and beauty of our choice 

 specimens. Cultivation has multiplied the va- 

 rieties of the pear almost to infinity, and pro- 

 duced them all from one worthless species. The 

 peach, in its wild state, in Media, is poisonous ; 

 but cultivated in the plains of Ispahan and Egypt, 

 it becomes one of the most delicious of fruits. 

 But in few plants are the effects of cultivation 

 more apparent than in the Brassica tribe. How- 

 ever extravagant it may appear, all the varieties 

 of red and white cabbage, savoys, brussels-sprouts, 

 winter greens, cauliflowers arid broccolis, have 

 sprung from one poor arid insignificant-looking 



