THE EVOLUTION OF PLANTS 



of the telephone, to deny his existence, nor to cease to admire 

 him and his work. Moreover, by understanding the tele- 

 phone he was in a position to understand its inventor more 

 intelligently and to regard him with more admiration and 

 reverence. 



Do we enjoy the modern delicious varieties of fruits and 

 vegetables and the wonderfully beautiful horticultural forms 

 and colors of flowers? These were produced, not by Nature 

 unaided, but by Nature aided by Man. The success of men 

 in breeding the numerous horticultural varieties of plants 

 depended upon their understanding the processes by which 

 new forms of plant life come into existence. 



But an understanding of the method by which the present 

 condition of the plant kingdom was brought about has value 

 from an entirely different point of view. It gives us a more 

 intelligent comprehension of Nature, it widens our intel- 

 lectual horizon, it reveals a world of law and order, not of 

 caprice and chance, and it enables us better to understand 

 ourselves and our relation to the world in which we live. 



In the earlier periods of intellectual inquiry men 

 endeavored to reach an understanding of Nature by philo- 

 sophical speculation. But, as Mackenzie ^ has well said, just 

 as the special sciences cannot furnish us with those ultimate 

 explanations for which the human mind inevitably looks, 

 so "no purely philosophical speculation can tell us about 

 the particular structure of the world in which we find our- 

 selves." There is only one source of evidence and light, 

 and that is the study of Nature itself. If we would know 

 how the present condition of the plant world came about 

 we must study plants. Let us, then, briefly present some of 

 the more important general truths that have been brought to 

 light by the study of plants. 



^ Mackenzie, J. F., Elements of Constructive Philosophy, p. 308. 



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