208 The Development of the Grain oj Wheat 



it is seen to increase for the first three or four periods {i.e. while the 

 living tissues of the pericarp form the most prominent feature in the 

 grain), then it falls rapidly, and during the last fortnight it remains 

 approximately constant, though the figures are evidently affected by a 

 large experimental error. 



Plot 3 

 Plot 10 



3 6 9 12 15 18 21 24 27 30 33 36 39 days 



Fig. 13. Maltose produced per 100 of dry matter, 1907. The dark line shows the mean 

 curve for the three plots, placed three squares too low for the sake of clearness. 



Determinations of the diastatic power were made by rapidly 

 macerating the fresh grain and adding it to starch paste : Fig. 13 

 shows the amount of maltose thus produced per 100 of dry matter in 

 the grain. The results are subject to a large experimental error, but 

 indicate that the diastatic power of the material, taken as a whole, 

 rises during the first four or five periods and then falls steadily. 

 Again recalculating the results to show diastatic power per 1000 grains 

 (Fig. 14), this property rises for five periods and then probably remains 

 constant. 



Owing to an accident only one set of determinations of protein 

 nitrogen are available, for 1908 ; these show (Fig. 15) a marked rise in 

 the proportion of nitrogen in the protein form during the period of 

 experiment. At first about 72 per cent, of the nitrogen is combined as 

 protein but this gradually rises to over 99 per cent. 



On the same figure is shown the actual amount of non-protein 

 nitrogen contained in 1000 grains ; it rises at first, then remains 

 approximately constant, and finally falls rapidly during the last desic- 



