CHAPTER XI 



THE WAYS IN WHICH PLANTS PERPETUATE THEIR KINDS, 

 AND MULTIPLY THEMSELVES IN NUMBER 



Reproduction 



? all the facts about life, no one is more fundamental 

 or familiar than this, that individuals inevitably die. 

 Obviously they must be replaced if the race is to con- 

 tinue, and this replacement is the office of reproduction, 

 which we must now proceed to consider. Our study of the subject 

 will have all the more interest for the reason that, like several 

 others of the physiological processes, reproduction is substantially 

 identical in meaning and method in animals and plants, differing 

 only in some external features connected with their differences 

 in habit. Therefore any knowledge acquired in one kingdom can 

 be transferred to the other; and one may learn from plants the 

 essential nature of reproductive processes in animals, including 

 mankind. 



The central fact of reproduction is the formation of new in- 

 dividuals capable of growing into kinds closely like those which 

 produced them. Associated therewith, however, is the further 

 fact that usually the formation of a new individual requires the 

 cooperation, through the act of fertilization, of two parent in- 

 dividuals of different sexes; and so prominent is this feature, 

 especially among the higher animals, that most people consider 

 it an indispensable feature of reproduction. This idea, however, 

 is not correct, and the two things, formation of new individuals 

 and sexual union, though so often associated, are quite inde- 

 pendent in their nature, as is shown by the fact that purely 

 non-sexual, or asexual, reproduction exists abundantly, not only 



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