CONTENTS 7 



PAGE 



PART II. THE REPRODUCTIVE ORGANS 



CHAPTER XII 



BIOLOGY OF THE FLOWER. DICOTYLEDONS 



I. Pollination of Simple Flowers by Wind and Insects 



Structure and functions of the flower. Sepals, petals, stamens, 

 carpels. Wind-pollinated flowers. Self-pollination. Insects 

 as pollinators. Mouth-parts of insects. Pollen-flowers. Peri- 

 gynous and epigynous flowers ; the flower-tube. Devices to 

 secure cross-pollination . . . . . . .156 



CHAPTER XIII 



BIOLOGY OF THE FLOWER (continued) 



II. Pollination of Tubular and highly developed Flowers 



Dimorphic, trimorphic, and cleistogamous flowers. Irregular 

 bee-flowers. Summary of the chief types of flower-structure 

 in Dicotyledons . . . . . . . .174 



CHAPTER XIV 

 BIOLOGY OF THE FLOWER (continued) 



Monocotyledons 



Simple trimerous flowers. Complex irregular flowers of Iris 

 and Orchis. Grass flowers. Summary of flower-structure in 

 Monocotyledons . . . . . . . .194 



CHAPTER XV 



POLLINATION, FERTILIZATION, AND THE ORIGIN OF 



SEEDS 



The chief methods of pollination. Nectaries. Structure of the 

 pistil and ovules. Fertilization. Changes resulting from 

 fertilization 203 



CHAPTER XVI 



STRUCTURE OF FRUITS 



Dry fruits : {a) Indehiscent : Nuts, achenes, samaras, and 

 cremocarps. (b) Dehiscent : Follicles, legumes, siliquas, and 

 capsules. Succulent fruits : Drupes, berries, pomes, and com- 

 pound fruits . . . . . . . ..211 



