THE PATH OF EVOLUTION 



starch and organic matter prepared during the day- 

 light, but partly consumed then, as well as at night. 

 It is well known, moreover, that all grasses lose most 

 of their nutritive properties after the formation of 

 seed is completed. 



When the young plant begins its independent life, 

 or germinates, it requires at first no extraneous food, 

 nor does it require sunlight. It contains within 

 itself all that is needed excepting the energy furnished 

 by moderate warmth, and the addition of a little mois- 

 ture. With these supplied the seed protrudes a portion 

 of its substance through an opening, or openings, in the 

 outer coat; this thread or stem-like growth divides, 

 one part striving up to the light and air, the other 

 seeking the ground, if below it. 



If at this time, before more changes occur, the seed 

 be chemically examined, it will be found that with the 

 first appearance of a sprout the contents of the seed 

 have swollen, the starch has become sweet, and in a 

 little time will change entirely into sugar, which again 

 will disappear as the sprout increases, until roots 

 and the rudimentary form of leaves appear. If 

 now, the whole plant be removed and weighed, 

 it will be found that, notwithstanding its increased 

 bulk by moisture absorbed, it will weigh less than it 

 did before it began to grow, the growth being not 

 by the absorption of matter from without, but by the 



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