THE ECONOMIC BIOLOGY OF PLANTS 



451 



Legumes. Next in importance to the cereals among the 

 seeds used for food are the legumes (peas, beans, and lentils) all 



FIG. 139. Peanut (Arachis hypoga, Pulse Family, Leguminosai). 



A , lower part of a plant showing the leaves and flowers above ground, and 

 ripening nuts and roots below; the surface of the ground indicated at el. B,SL 

 flower cut vertically to show, at the base, the small ovary containing the ovules, 

 and the long style extending through a slender tube which is surmounted by 

 the calyx and cirolla and is continued by a tube formed of the united filaments. 

 >C, a ripe nut cut lengthwise to show the two seeds. (Tanbert.) The plant 

 is an annual, i.e., it completes its life from seed to seed in one year; stems and 

 leaves somewhat hairy; flowers orange-yellow, fruit pale. Soon after pollen 

 has come upon the stigma, the stamens and corolla are shed and the ovary is 

 carried out beyond the calyx by a stalk which becomes 5-8 cm. long, and, 

 bending downwards, soon buries the little ovary in the ground. Once buried 

 the ovary ripens into the familiar pod-like nut. If it fails to get buried the 

 ovary withers. From Sargent. 



