XIV 



CONTENTS. 



CHAPTER 



XIX. Colours of Flowers 



XX. The Emergence of the Floral Whorls 



XXI. The Development of the Floral Whorls 



XXII. Heterogamy and Autogamy ... 



XXIII. Heterostylism 



XXIV. Partial Diclinism 



XXV. Sexuality and the Environment... 



XXVI. Degeneracy of Flowers 



XXVII. Degeneracy of Flov^-ees— Continued 



XXVIII. Progressive Metamorphoses ... 



XXIX. Eetrogressive Metamorphoses 



XXX. Phyllgdy of the Floral Whorls 



XXXI. The Varieties of Fertilisation ... 



XXXII. F£ETILIi=ATI0N AND THE OrIGIN OF SpECIES 



PAGE 



174 



184 

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 198 

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 2.51 

 273 

 285 

 295 

 301 

 311 

 329 



