ORGANIC CONSTITUENTS. 



29 



nitrate culture and the least in the potash solution. The disappear- 

 ance of the reducing sugars is manifest in the control as well as in the 

 culture medium. As will be noted, the hydrolyzable sugar has also 

 entirely disappeared from the seed. 



Table 15. — Hydrolyzable sugars (as dextrose) in residual seeds and axes ivhen grown for 

 15 days in solutions containing one nutrient. 



Parts of plant and age. 



Control 

 solution. 



Nitrate 

 solution. 



Potash 

 solution. 



Phos- 

 phoric 

 acid solu- 

 tion. 



Original seed. 



Seeds: 



3 days... 



5 days... 



7 days... 



9 days... 

 12 days... 

 15 days... 

 Axes: 



3 days... 



5 days... 



7 days... 



9 days... 



12 days... 



15 days... 



Total plants: 



3 days... 



5 days... 



7 days... 



9 days... 

 12 days... 

 15 days... 



Mg. 



60 



53 



60 



Lost. 



Trace. 



2 



50 

 42 

 46 

 18 

 60 

 13 



110 

 95 



106 



Mg. 



95 



22 

 9 



103 

 96 

 97 

 66 

 23 



Mg, 



95 



52 



76 

 49 

 61 

 24 



117 

 106 

 135 



82 

 61 

 24 



Mg. 



95 



60 

 49 

 39 

 25 

 14 

 



43 

 46 

 50 

 45 

 52 

 19 



103 

 95 

 89 

 70 

 66 

 19 



Beginning with 95 milligrams of hydrolyzable sugar in 100 seeds, 

 the decrease was steady and rapid, and on the 15th day no trace 

 of sugar was found. There is no evidence of any new formation of 

 hydrolyzable sugar in the seed, as no increase was observed at any 

 time. The total amount found in the whole plant (seed + axes) never 

 really exceeds that originally found in the seed, indicating either that 

 the hydrolyzable sugar is translocated as such from the seed to the 

 axes, or that it is hydrolyzed before translocation occurs. There is a 

 small amount left in the axes on the fifteenth day. In the axes of 

 three-day-old plants the amount of hydrolyzable sugar is about one- 

 half that in the original seed. This is gradually decreased until on 

 the 15th day there is only a small amount left. These results are 

 the same in the control solution as in the nutrient solutions. 



There is no increase of hydrolyzable sugar in the seed, and while 

 there is no reducing sugar present in the beginning, on the fifth day 

 the amount of reducing sugar is twice that of the total hydrolyz- 

 able sugar present originally. That this increase in reducing sugar in 

 the residual seed is the result of hydrolysis of the starch contained 

 therein is most probable, but whether the sugars found in the axes 

 are due entirely to the hydrolysis of the starch of the seed and sub- 

 sequent translocation into the axes, or whether a part of these sugars 

 is the result of assimilation, has not been determined. 



