LESSON 12.] 



ITS PAETS OK ORGANS. 



87 



Fig. 169, d, but on a larger scale, and with the ovary cut across, 

 shows the ovules as they appear in a transverse 

 section. The style (Fig. 171, b) is the tapering 

 part above, sometimes long and slender, sometimes 

 short, and not rarely altogether wanting, for it is 

 not an essential part, like the two others. The 

 stigma (c) is the tip or some other portion of the 

 style (or of the top of the ovary when there is no 

 distinct style), consisting of loose tissue, not cov- 

 ered, like the rest of the plant, by a skin or epi- 

 dermis. It is upon the stigma that the pollen 

 falls ; and the result is, that the ovules contained 

 in the ovary are fertilized and become seeds, by 

 having an embryo (16) formed in them. To the 

 pistU, therefore, all the other organs of the blos- 

 som are in some way or other subservient : the 

 stamens furnish pollen to fertilize its ovules ; the 

 corolla and the calyx form coverings which pro- "^ 



tect the whole. 



234'. These are all the parts which belong to any flowei> But 

 these parts appear under a variety of forms and combinations, some 

 of them greatly disguising their natural appearance. To understand 

 the flower, therefore, under whatever guise it may assume, we must 

 study its plan. 



