THE FERTILISATION OF FLOWERS 



3" 



being to form a protective envelope for the other organs 01 the flower. 

 Within the calyx, we descry the corolla (Fig. 208, co]. This is the circle 

 of petals or leaves which, par excellence, we call the " flower," because 

 it constitutes in the vast majority of flowers the bright and showy portion 

 thereof. A flower might botanically or physiologically be perfect enough 

 minus its corolla; al- 

 though the eye, missing 

 the bright petals, would 

 be apt to regard such 

 a plant as wanting the 

 first and chiefest ele- 

 ment of the blossom. 

 The common nettle, 

 for instance, appears to 



possess no " flowers " in F!G - 209. NETTLE-FLOWERS. 



the popular and accus- 

 tomed sense of the term ; but when we examine the plant, we readily 

 discover that it possesses parts corresponding to the flowers (Fig. 209) 

 of other plants. In the greater nettle, the flowers of one plant are es- 

 sentially different (in that they possess " stamens " (Fig. 209 s s) alone) 



FIG. 210. FEMALE OR PISTILLATE 

 FLOWERS OF WILLOW. 



FIG. 2ii. MALE OR STAMINA TE 

 FLOWERS OF WILLOW. 



from those of another plant (which possess " pistils " (/) only). But 

 in the lesser nettle, or in the oak, these distinct flowers (Figs. 212, 213) 

 are found on one and the same plant. No vestige of colour appears 

 in either, however ; and when we study the flowers in question, we 



