STRUCTURE OP THE FLOWER AND ITS ORGANS. 147 



called the stigma. These parts are all shown in Fig. 128. 

 In many pistils the stigma is borne directly on the ovary, as 

 in Fig. 145. 



182. Union of Stamens with each Other. — Stamens may be 

 wholly unconnected with each other or distinct, or they may 

 cohere by their filaments into a single 

 group, when they are said to be monadel- 

 phous, of-one-brotherhood, Fig. 129, into 

 two groups (diadelphous), Fig. 130, or 

 into many groups. In some flowers the 

 stamens are held together in a ring by 

 their coherent anthers, Fig. 131. 



183. Union of Pistils. — The pistils 

 may be entirely separate from each other, 

 distinct and simple as they are in the 

 buttercup and the stonecrop, or several 

 may join to form pne compound pistil of 

 more or less, united carpels. In the 

 latter case the u;nion generally affects the 

 ovaries, but often leaves the styles sep- 

 arate, or it may result in joining ovaries 



and styles, but leave the stigmas separate 

 or at any rate lobed, so as to show of how 

 many separate carpels the compound pis- 

 til is made up. Even when there is no 

 external sign to show the compound 

 nature of the pistil, it can usually be 

 recognized from the study of a cross- 

 section of the ovary. 

 184. Cell of the Ovary; Placentas. — Compound ovaries 

 are very commonly several-celled, that is, they consist of a 

 number of separate cells ^ or chambers. Fig. 132 B shows a 



1 Notice that the word cell is here used in an entirely different sense from that 

 in which it has been employed in the earlier chapters of this book. As applied to the 

 OTary, it means a chamber or compartment. 



Fig. 123. — Salver-Shaped 

 Corolla of .Jasmine 

 (magnified). 



Fig. 124. —Wheel-Shaped 

 Corolla of Potato. 



