THE BEAN 



ISI 



is on one side — the side of the seed that is somewhat hol- 

 lowed. Near one end of this scar is a small hole — the 

 micropyle. 



173. The Fruit (Fig. 92). — As the ovules grow into 

 seeds, the ovary that contains them develops into a fruit 

 (the pod). It grows rapidly. In the case of those varieties 

 whose young pods are eaten in the form of 

 " string beans," they are large enough for 

 use ten or twelve days after pollination. 

 The ovary is horizontal or nearly so, as 

 we have seen, when the flower opens. 

 But as it grows after fertilization, its 

 weight bends the pedicel, and it hangs 

 downward. The walls of the pod are 

 green or greenish at first, but sooner or 

 later they change, usually to yellowish or 

 brownish, sometimes to other colors,' and 

 become thin, dry, and hard. The pods of 

 some varieties are still green at the string 

 bean stage ; those of others are yellow at 



this time. 



rn, u r ii J. 1 • pod removed, show- 



The base of the style remams as a ^g the seeds ^nd the 



pointed projection at the end of the pod ; way in which they 



the rest of the style and the stigma wither are attached; a, the 



r. 11- J.- A 11 J. r remains of the style : 



alter pollination. A small amount of j ^j^^ sepals 



tissue develops between the seeds, so that 

 each one lies in a separate cavity ; but as the fruit ripens 

 these partitions dry and shrivel away. A ripe pod shows 

 a bulge corresponding to the position of each seed. In a 

 cross section through the pod of many varieties of bean 

 (Fig. 93), one sees a group of vascular bundles, containing 

 many thick-walled cells, near one edge of the section, and 

 two similar but smaller groups near the opposite edge. 

 The inner layer of the pod also contains thick-walled 

 cells. The groups of bundles near the edges of the pod 



Fig. 92, — A bean 

 fruit with half of the 



