STRUCTURE OF THE FLOWER AND ITS ORGANS 203 



separate cells 1 or chambers, more scientifically known 

 as locules. Fig. 154, B, shows a three-celled ovary 

 seen in cross-section. The ovules are not borne indis- 

 criminately by any part of the lining of the ovary. In 

 one-celled pistils they frequently grow in a line running 

 along one side of the ovary, as in the pea pod (Fig. 271). 

 The ovule-bearing line is called a placenta; in compound 

 pistils there are commonly as many placentas as there are 



FIG. 147. Tubu- 

 lar Corolla, from 

 Head of Bache- 

 lor's Button. 



FIG. 148. Labi- 

 ate or Ringent 

 Corolla of Dead 

 Nettle. 



FIG. 149. Parts of a 



Stamen. 



A, front ; B, back ; a, an- 

 ther ; c, connective; 

 /, filament. 



FIG. 150. Parts 

 of the Pistil. 



ov, ovary. 

 sty, style. 

 stig, stigma. 



separate pistils joined to make the compound one. Pla- 

 centas on the wall of the ovary, like those in Fig. 154, A, 

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

 in the same figure, are said to be central, and those which, 

 like the form represented in of the same figure, consist 

 of a column rising from the bottom of the ovary are 

 called free central placentas. 



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

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

 applied to the ovary, it means a chamber or compartment. 



