COMPOSITION IN SUCCESSIVE STAGES. 207 



On dividing the above quantities by the number of days 

 of the respective periods, there results : 



The Average Daily Gain or Loss per Acre during 

 each Period. 



4. Table III, and especially Tab. IV, show that the gain 

 of organic matter in Bretschneider's oat-crop went on 

 most rapidly at or before the time of blossom, (according 

 to Arendt at the time of heading out.) This was, then, the 

 period of most active growth. Afterward the rate of 

 growth diminished by more than one-half, and at a later 

 period increased again, though not to the maximum. 



Absolute Quantities of Carbon, Hydrogen, Oxygen, 

 Nitrogen, and Ash, in the dry oat crop at the conclusion of 

 the several periods ; (Ibs. per acre.) 



' TABLE V. Br. 



Carbon. Hydrogen. Oxygen. Nitrogen. Ash.* 



1st Period, 593 80 455 46 110 



3d " 2,137 286 1,575 122 263 



4th " 2,600 343 2,043 150 291 



5th " 3,229 405 2,713 167 372 



Relative Quantities of Carbon, Hydrogen, Oxygen, 

 Nitrogen, (Organic Matter,) and Ash in the dry oat crop, 

 at the end of the several Periods ; (per cent.) 



TABLE VI. Br. 



Carbon. Hydrogen. Oxygen. Nitrogen. (Organic Matter.) Ash. 

 1st Period, 46.22 6.23 35.39 3.59 91.43 8.57 



3d " 48.76 6.53 35.96 2.79 94.04 5.96 



4th " 47.91 6.33 37.65 2.78 94.67 5.33 



5th " 46.89 5.88 39.40 2.43 94.60 5.40 



* In Bretschneider's analyses, "ash" signifies the residue left after carefully 

 burning the plant. In Arendt's investigation the sulphur and chlorine were de- 

 termined in the unburncd plant, 



