CHAPTEE II. 

 SEED-GERMINATION AND SEEDLING-GROWTH. 



15. Seed-germination. "With an ordinary magnifying- 

 glass the tiny plantlet is not difficult to discover compactly 

 folded up within the seed. If we place seeds, of pumpkin, 

 bean, corn, or pea in boiling water until fully swelled, 

 and then carefully dissect them, we will soon find the 

 embryo plantlet which exists in all seeds grown by the 

 horticulturist. What is known as sprouting or germina- 

 tion is merely the UD folding and growth of the embryotic 

 plant. Some of the soil requisites and other favoring con- 

 ditions for germination have been given in the preceding 

 chapter. The mature seed contains starch or protoplasm 

 in dormant condition. When placed in moist soil, with 

 temperature suited to the variety or species, the proto- 

 plasm becomes active, as when the spring awakens activity 

 of circulation and growth of dormant trees in spring. 



The cells of the embryo begin to increase in number by 

 division, and soon the tiny shoot, known popularly as the 

 sprout and by botanists as the hypocotyl, starts downward. 

 If the seed is not properly placed, this first growtli will 

 make a curve before the rounded point extends downward. 

 In the forest we often see the acorn, lying on moist leaves, 

 project the hypocotyl through the leaves to the moist 

 earth, and later, when fastened to the soil, the up-growing 



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