GERMINATION OF SEEDS 



59 



What precaution should be observed in mills and grain 

 elevators to keep the seeds from sprouting? 



Suggestion. Visit a malting house and observe the pro- 

 cess of making malt. Procure some grain not yet malted 

 and compare it with that which has been malted. Test 

 both for starch and for grape sugar. How do they differ ? 



Note. It will be seen that starch changes into grape sugar 

 during germination. This is effected by a substance called diastase, 

 which is known as a ferment because it can cause fermentation. 

 This change is necessary to the plant, since the starch is not capable 

 of diffusing through the tissues of the plant. But by being changed 

 to sugar it can be carried to all parts of the plant. 



43. THE WATER FACTOR 



Object. To find out wlwther all seeds require the 

 same conditions of water to grow. 



Apparatus. A shallow pan, a plate of glass 4 in. X 12 in., blot- 

 ting paper, and assorted seeds. 



Note. Small seeds, such as lettuce, clover, alfalfa, timothy, blue 

 grass, and the grains, are better than others for this experiment. 



Method. Cover the glass plate with one or two thick- 

 nesses of blotting paper and plant the seeds upon the paper 



FIG. 15. 



in straight rows from end to end. Then place the covered 

 plate so that one end rests on the bottom of the pan and 



