88 SOUTH AFRICAN FLOWERING PLANTS. 



Now remains the pistil. The lower part is the 

 ovary, the short contracted piece above it is the style, 

 while the stigma is the somewhat rounded rough top. 

 The pistil is composed of two carpels as the diagram 

 (Fig. 31, II.) will show. This is supposed to represent 

 a flower cut across. The four outer crescents stand for 

 the sepals, the four inner the petals, the six black 



L 



Fig. 31, — I. Tetradynamous stamens and pistil of aCrucifer: 

 a, shorter, 6, longer stamens. II. Floral diagram. 



spots are the anthers, and the oval in the middle is the 

 ovary of the pistil, the little projections being the 

 ovules. It will be observed that these are not in 

 the middle of the ovary, but on the wall, while the 

 parietal placentas, or the thickened margins of the 

 carpels, are connected by a plate, half of which has 

 grown out from each side and united in the middle. 

 In order to understand how this cohesion ^ between the 



^ The word cohesion is used when the parts of any whorl are 



