LESSON 15.] fHE CALYX AND COROLLA. 99 



259. Moreover, the arrangement of the parts of the flower answers 

 to that of leaves, as illustrated in Lesson 10, — either to a succes- 

 sion of whorls alternating with each other in the manner of whorled 

 leaves, or in some regular form of spiral arrangement. 



LESSON XV. 



MORPHOLOGY OF THE CALYX AND COROLLA. 



260. Hating studied the flower as a whole, we proceed to con- 

 sider more particularly its several parts, especially as to the principal 

 differences they present in diflPerent plants. We naturally begin 

 with the leaves of the blossam, namely, the calyx and corolla. And 

 first as to 



261. The Growing together of Parts. It is this more than anything 

 else which prevents* one from taking the idea, at first sight, that the 

 flower is a sort of very short branch clothed with altered leaves. 

 For most blossoms we meet with have some of their organs grown 

 together more or less. We have noticed it as to the corolla of Ge- 

 rardia, Catalpa, &c. (Fig. 194-196), in Lesson 13. This growing - 



PIG. 198. Succession of sepals, petals, gradations between petals and stamens, and true 

 •tamens, of the Nymphsa, or White Water-LUy. 



