8 



ELEMENTS OF STRUCTURAL BOTANY. 



Fig. 11. 



You will notice that the carpel ends, at the top, in a 

 little bent point, and that the convex edge is more or 

 less rough and moist, so that in flowers 

 whose anthers have burst open, a quan- 

 tity of pollen will be found sticking there. 

 This rough upper part of the carpel is 

 called the stir/ma. Fig. 11 shows a stigma 

 greatly magnified. In many i)lants the 

 stigma is raised on a stalk above the ovary. Such a 

 stalk is called a style. In the Buttercup the style is so 

 short as to be almost suppressed. "When the style is 

 entirely absent the stigma is said to be sessile. The 

 hollow part of the carpel is the ovary. 



In our plant the pistil is not connected in any way 

 with the calyx, and is consequently said to be free or 

 superior, and, as the carpels are not united together, 

 the i^istil is said to be apocarpous. 



8. Kemove now all the carpels, and there remains 

 nothing but the swollen top of the peduncle. This 

 swollen top is the recejotade of the flower. To it. in the 

 case of the Buttercup, all four parts, calyx, corolla, 

 stamens, and pistil, are attached. When'Vflower has 

 all four of these parts it is said to be complete. 



9. Let us now return to our statement that the struc- 

 ture of stamens and j'istils is only a modi- 

 fication of leaf- structure generally. The 

 stamen looks less like a leaf than any other 

 part of the flower. Fig. 12 will, however, 

 serve to show you the plan upon which the 

 botanist considers a stamen to be formed. 

 The anther corresponds to the leaf-blade, 

 and the filament to the petiole. The two 

 cells of the anther correspond to the two 



Fis. 12 



