4 NATURE TEACHING 



Plant Food in Seeds. 



The first stages of germination take place at the 

 expense of the store of plant food which exists in every 

 seed. In the case of the bean, which has just been 

 examined, the store of plant food is contained in the 

 thickened seed-leaves. If some germinating kidney 

 beans, growing in soil, are observed from day to day, 

 it will be seen that the seed-leaves gradually become 

 smaller and smaller, and finally shrivel up. In the 

 scarlet runner a similar thing happens, although here 

 the cotyledons never came above the surface of the 

 ground. A great many plants with which we are 

 familiar have their supply of plant food for germination 

 stored away in the seed-leaves ; this, for instance, is the 

 case with all the peas and beans, with the seeds of 

 oak, apricot, cabbage, radish, lettuce, cucumber, orange, 

 and many others. 



There are many seeds in which the store of plant 

 food for germination is not contained in the seed-leaves, 

 nor in any other part of the small plant in the seed, but 

 exists as a separate store. In these seeds we find 

 inside the seed-coat an embryo, as in the bean, but only 

 small cotyledons, and, in addition, a separate store of 

 plant food. These may be made out in the seed of 

 buckwheat,, marvel of Peru, etc., where the embryo is to 

 be seen enveloping, but perfectly distinct from, the store 

 of plant food which makes up the greater portion of 

 the seed. . 



In wheat, barley, maize, etc., the embryo lies at one 

 side of the seed, near the pointed end (base), and easily 



