ACTION OF FLOWEBS. 55 



CHAPTER V. 



ACTION OF FLOWERa 



Strticture of Flowers. — Names of their Parts. — •Ten- 

 dency of the Parts to alter and change, into each other^ 

 and into Leaves. — Double Flowers.— Analogy of 

 Flowers to Branches. — Gav.se of (he Production of 

 Flowers. — Of Productiveness. — Of Sterility. — Uses of 

 the Parts of a Flower. — Fertilization. — -Hybrids.-^ 



79. A Flower is that part of a plant which is 

 formed for the purpose of reproducing the species 

 by means of seeds. It consists of floral envelopes 

 and sexes. 



80. The floral envelopes are : 1. the calyx, which 

 is usually green, and always the most external ; andj 

 2. the Corolla, which is Commonly thin, gaily coloured^ 

 more fugitive than theicalyx, and placed next within 

 it ; each of these consists of leaves, called sepals in the 

 calyx, and petals in the corolla; Both calyx and 

 corolla are usually present ; but in some cases only 

 one envelope is formed, as in the Marvel of Peru ; and 

 in other cases the flower has no envelopes, as in the 

 Willow. Envelopes are, therefore, not a necessary 

 part of a flower. > ' • 



81. In the middle of. the flower stand the sexes, 



