38 THE PLANT. 



in the 21 clays of the 3rd and 4th stages to as much as in 

 the 61 days of the 1st and 2nd stages : in other words, 

 the overground organs of the plant gained of these two 

 ingredients, in the flowering and ripening time, three times 

 as much each day as in the preceding period. 



Of the turnip-plant we know with tolerable certainty, 

 that from the time when it sends forth a flower-stalk, the 

 constituents of the stalk, as also those of the flowers and 

 the seeds, are for the most part stored up in the root, and 

 are supphed therefrom. It is highly probable that the 

 corn-plant is similarly circumstanced, and that from the 

 flowering to the end of life it is fed, though not exclu- 

 sively, by the root, which from the flowering time gives 

 out what it had stored up in the preceding period. 



Knop observed that Indian corn plants in flower, taken 

 out of the ground and placed with their roots simply in 

 water, produced ears with ripe seeds ; which proves that 

 the materials serving for the production of seed were 

 already present in the plant at the time of flowering. 



It is an established fact that a corn-plant, if cut ofi" 

 before flowering, relapses into that lower stage of vege- 

 tation of a perennial plant, in which the root receives 

 more organisable matter than it parts with.* 



The proportions of incombustible constituents and of 

 nitrogen severally required by oats and turnips, are 

 remarkably different, both in the aggregate and during 

 the various stages of growth. The facts established by 

 Anderson for the turnip, and by Ahrends for the oat, are 

 indeed not sufficiently numerous to warrant us in deducing 



* Buckmann (' Journ. of the Royal Agric. Soc.') sowed wheat on 

 a field in autumn 1849, which was continually cut down in 1850, so 

 that the plants were never allowed -to come to flower : they were left 

 in during the winter 1850-51, and yielded an excellent crop in the 

 year 1851. 



