CHAPTER XVII 

 THE LEGUMES 



444. What Legumes Are. The term " legume" was 

 originally applied to any plant belonging to the order Legum- 

 inoseae, 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 

 several families, the largest and most important of which is 

 the Papilionaceae, in which are included practically all the 

 cultivated 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, alfalfa, the vetches, peas, beans, soy 

 beans, cowpeas, and numerous other plants of less impor- 

 tance. 



445. 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 

 usually 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 

 usually 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 



