PREFACE 



acquaintance with the earher, the non-botanist 

 will be well advised to read them in the order 

 placed, but for those who have already some 

 knowledge of botany this sequence is immaterial. 



In a work of this class it would be folly 

 for the author to pretend to originality, for he 

 would be courting disaster to ignore the recognised 

 working hypotheses and valuable suggestions of 

 such authorities as Darwin, Kerner, H. Miiller, 

 Sprengel, Grant Allen, Lubbock (Lord Avebury), 

 Ogle, Wallace, Spencer, and others. The founda- 

 tion of this volume is necessarily laid on the 

 work of previous inquirers. 



Nevertheless, the author of a book or this 

 character should not shrink from offering sugges- 

 tions on points which appear to have been 

 overlooked or ignored by previous writers ; 

 and therefore, while the various plants treated 

 of were under my consideration, I attempted 

 to explain the meaning of any structure, or 

 any aspect in their economy, that seemed to 

 present a hitherto unsolved problem. Why are 

 the leaves of the wild orchid spotted ? Why is 

 it that the wild camomile opens wide its flower- 

 head at night, and the similar inflorescence of 

 the field daisy closes ? Why do the stonecrops 

 still retain the parts of their flowers in whorls 

 of five ? These inquiries represent the class of 



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