THE BEAN 145 



Since these edges touch each other, all the ovules lie nearly 

 in a straight line ; but if a pod is split open, we can see 

 that in reality some of the ovules are attached to one edge 

 and some to the other. Each ovule (Fig. 87) has a thick 

 stalk, which is bent in such a way that the body of the 

 ovule is turned part way backward and its free end (with 

 the micropyle) is near the wall to which the stalk of the ovule 

 is attached. Two integuments are formed about the ovule, 

 instead of only one as in the pine ; they leave a narrow open- 

 ing (the micropyle) at the free end of the ovule. 



The long, slender part of the pistil above the ovary is the 

 style ; the style, which contains a slender canal that is con- 

 tinuous with the cavity of the ovary, bends near the ovary 

 and turns upward ; it lies inside the keel, and so its upper 

 part is coiled in the same way that the end of the keel is. 

 The upper end of the style is a little thickened, and on the 

 inner side of this thicker part is the stigma. The surface 

 of the stigma is rough, and when it is touched a sticky 

 liquid oozes from it. The ovary and the lower part of the 

 style are covered with many short hairs, and there is another 

 brush -like group of hairs on the inner side of the upper part 

 of the style, just below, and on the sides of, the stigma. 



169. The Female Plant. One cell within the ovule 

 grows to be much larger than any of the others ; this is the 

 macrospore mother cell (d, Fig. 87). It divides to form a 

 row of three macrospores (instead of four, as in the pine) ; 

 and one (the largest) of these, macrospores, as in the pine, 

 develops into a female plant (Figs. 88 and 89). 



But the female plant of the bean is much smaller and simpler than 

 the female plant of the pine. It consists of only seven cells. Each 

 cell has one nucleus, except that the central cell, which is much the 

 largest, contains two nuclei (Fig. 89, /). At the end of the female 

 plant nearest the micropyle is a group of three cells ; one of these 

 three is the egg (Fig. 89, d). This little seven-celled plant remains 

 throughout its life, like the female plant of the pine, shut up inside the 

 ovule. 



