STRUCTURE OF THE FLOWER AND ITS ORGANS. 149 



all inserted on the receptacle, and the corolla and stamens 

 are said to be hypogynous, that is, beneath-the-pistil. In- II 

 the petals and the stamens appear as if they had grown fast 

 to the calyx for some distance, so that they surround the 

 pistil, and they are therefore said to be perigynous, that is, 

 around-the-pistil. In III all the parts are free or uncon- 



PiG. 130. — Diadelphous 

 Stamens of Sweet Pea. 



Fio. 129.— Mona- 

 delphous stamens 

 of Mallow. 



A' ~B~ ' C 



Fig. 132. — Principal Types of Placenta. 

 Aj parietal placenta ; B, central placenta ; 

 C, free central placenta ; A and S, trans- 

 verse sections ; C, longitxidinal section. 



Fig. 131. — Stamens of 

 a Thistle, with An- 

 thers United into a 

 Eing. 

 a, united anthers ; /, 

 filaments, bearded 

 . on the sides. 



solidated, except the petals and stamens; the stamens may 

 be described as epipetaloics, that is, growing-on-the-petals. 

 Sometimes some or all of the other parts seem to grow out of 

 the ovary, and such parts are said to be epigynous, that is, 

 on-the-ovary, like the petals and stamens of the white water- 

 lily, rig. 134. 



186. Floral Diagrams. — Sections (real or imaginary) 



