COMPOSITION IN SUCCESSIVE STAGKS. 209 
first stages of ripening, but falls off at last to minimum. 
The ratio of Oxygen to Carbon is the same during the Ist 
and 3d periods, but increases remarkably from the period 
of full blossom until the plant is ripe. 
As already stated, the largest absolute assimilation of 
2li ingredients—-most rapid growth—takes place at the 
time of heading out, or blossom. At this period all the 
volatile elements are assimilated at a nearly equal rate, 
and at arate equal to that at which the fixed matters (asl) 
are absorbed. In the first period Nitrogen and Ash; in 
the fourth period Nitrogen and Oxygen; in the fifth pe- 
riud Oxygen and Ash are assimilated in largest propor- 
tion. 
This is made evident by calculating for each pcriod the 
Daily Increase of Each Ingredient, the amount of the in- 
gredients in the ripe plant being assumed at 100 as a point 
of comparison. The figures resulting from such a calcula- 
tion are given in 
TaBLE IX.—Br. 
Carbon. Hydrogen. Oxygen. Nitrogen. dsh. 
1st Period, 0.31 0.33 0.28 0.47 0.50 
3d Ke 2.51 2.68 2.17 2.59 2.13 
4th “ 0.89 0.88 1.07 1.06 0.47 
Sth “ 1.49 1.16 1.89 0.75 1.70 
The increased assimilation of the 5th over the 4th period 
is, in all probability, only apparent. The results of anal- 
ysis, as before mentioned, refer only to those parts of the 
plant that are above ground. The activity of tae foliage 
in gathering food from the atmosphere is doubtlexs greatly 
diminished before the plant ripens, as evidenced by the 
leaves turning yellow and losing water of vegetation. 
The increase of weight in the plant above ground probably 
proceeds from matters previously stored in the roots, which 
now are transferred to the fruit and foliage, and maintain 
the growth of these parts after their power of assimilatir g 
inorganic food (CO,, H,O, NH,, N,O,) is lost. 
