354 



PKACTICAL BOTANY 



The Leguminosce constitute the largest family of choripetalous 

 dicotyledons, an extremely important one on account of the 

 numerous useful species. The genera are divided into three 



FIG. 289. Pea family. Papilionaceous zygomorphic corolla of sweet pea 

 (Lalhyrus odoratus) 



A, side view. />, front view: s, standard; w, w, wings; k, keel 



sub-families (often ranked as families), of which the acacia, 

 the redbud (also the wild senna), and the sweet pea are respec- 

 tively well-known types (see Figs. 288 and 289). 



322. Edible seeds of the Pea family. Many seeds which form 

 an important part of human food are derived from this family. 

 The ones most generally used in our own country are peas 

 and beans. Peanuts are the seeds of a leguminous plant largely 



FIG. 290. Pea family. Stamens and pistil ; fruit 



A, stamens and pistil of sweet pea (magnified) ; B, fruit; C, part of fruit, 

 showing one seed 



grown in the South Atlantic states and elsewhere, which forces 

 its pods underground to ripen. Our crop of 4,000,000 or more 

 bushels per year is largely consumed at home, but is also con- 

 siderably exported. 



