THE SEED AND ITS GERMINATION 13 



12. Other Proofs of Chemical Action. — Besides the proof 

 of chemical changes in germinating seeds just described, 

 there are other kinds of evidence to the same effect. 



Malt, which is merely sprouted barley with its germi- 

 nation permanently stopped at the desired point by the 

 application of heat, tastes differently from the unsprouted 

 grain, and can be shown by chemical tests to have suffered 

 a variety of changes. If you can get unsprouted barley 

 and malt, taste both and see if you can decide what sub- 

 stance is more abundant in the malt. 



Germinating kernels of corn undergo great alterations 

 in their structure ; the starch grains are gradually eaten 

 away until they are ragged and* full of holes and finally 

 disappear. 



13. The Embryo and its Development. — The miniature 

 plant, as it exists ready formed and alive but inactive in 

 the s,eed, is called the embryo. In the seeds so far ex- 

 amined, practically the entire contents of the seed-coats 

 consist of the embryo, but this is not the case with the 

 great majority of seeds, as will be shown in the following 

 chapter. 



