130 



FLOWER OF THE HIGHER SEED PLANTS 



FIG. 136. Insertion of the floral organs 



pistil. Placentas on the wall of the ovary, like those in Fig. 135, 

 A, are called parietal placentas; those which occur as at B 



are said to be axial; and those 

 which, like the form repre- 

 sented in C, consist of a col- 

 umn rising from the bottom of 

 the ovary are called free cen- 

 tral placentas. 



157. Superior, half -inferior, 

 and inferior ovaries. When, 



A, hypogynous, all the other parts on the ag i n foe diagrammatic flower 

 receptacle, beneath the pistil ; 13, perig- . 



ynous, petals and stamens apparently 01 lg. LZZ, tne receptacle IS 



growing out of the calyx, around the roun( J e d or club-shaped, and 

 pistil ; C, epigynous, all the other parts f 



appearing to grow out of the pistil. the floral organs arise trom it 



After Strasburger in success i ve sets, the flower 



is said to be hypogynous (from two Greek words here applied 

 to mean under the pistil), and the ovaries are said to be 

 superior (Fig. 136, A). 



When the receptacle is concave, or when it grows up about 

 the pistil, carrying the other floral parts with it, so that 

 the pistil is inserted on the same 

 level with the stamens or lower, 

 but not at all united with the re- 

 ceptacle, the flower is said to be 

 perigynous (meaning around the 

 pistil) and the ovary is half infe- 

 rior (Fig. 136, B}. 



When the ovary is united with 

 the receptacle the flower is said 



to be epigynous (meaning upon 



,. . ... . . . , The inner petals and the stamens 



the pistil), or the OVary IS mfe- grow ing from the ovary. -After 



rior (Fig. 136, C). Decaisne 



158. Floral diagrams. Sections (real or imaginary) through 

 the flower lengthwise, like those of Fig. 136, help greatly in 

 giving an accurate idea of the relative position of the floral 



FIG. 137. White water lily 



