CHAPTER XVII 

 THE LEGUMES 



435. What Legumes Are. The term ''legume'^ was 

 formerly apphed to any plant belonging to the order Legumi- 

 noseae, the word being the Latin name for the kind of seed 

 pod which is borne by practically all plants of this group. 

 A legume in the original sense is a dry pod which opens along 

 both edges, or sutures, as the pod of the pea or bean, but the 

 term is now applied to any plant which belongs to this order. 

 Modern botanists have divided the Leguminoseae into sev- 

 eral families, the largest and most important of which is the 

 Papilionaceae, in which are included practically all the cul- 

 tivated legumes. This latter name is derived from the Latin 

 word papilio, a butterfly, from the resemblance of the flower 

 to that insect. Among the useful plants of this family are 

 the clovers, aKalfa, the vetches, peas, beans, soy beans, 

 cowpeas, and numerous other plants of less importance. 



436. General Characters. The legumes are decidedly 

 variable, yet they have many features in common. The 

 leaves are alternate and are usually compound. The flowers 

 are irregular as to size and shape of the petals, but are usu- 

 ally more or less butterfly-shaped. There are commonly 

 five petals, a broad upper one known as the standard or 

 banner, two lateral ones (the wings), and two front ones, 

 often more or less united (the keel). The stamens are usu- 

 ally ten in number, often united, or nine in one group and 

 one alone. The pistil is single and the ovary is one-celled, 

 but may contain a number of seeds. The fruit is a legume, 

 which splits open along both edges when mature. The seed 

 is almost entirely filled with the cotyledons, or seed leaves, 

 and on germination the entire seed often appears above 



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