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PASTORAL AND AGRICULTURAL BOTANY 



or small and exalbuminous that is, with the reserve food stored in the seed 

 leaves, or cotyledons, which become fleshy as a consequence. 



Economic Plants. The economic plants of the family are numerous 

 and their uses are manifold, on account of the presence of starch and 

 protein, as reserve materials in their seeds and other parts. Many legumi- 

 nous plants are used as human food. Such are the peas (Pisum), beans 

 (Phaseolus}, broad bean (Vicia), soy (Soja), peanut (Arachis), lentil (Lens}, 

 whose seeds are used in various ways, and the pods of carob (Ceratonia) 

 and tamarind (Tamarindus), are eaten by man. The fodder plants of 

 the family include the clovers (Trifolium), alfalfa (Medicago) sweet clover 

 (Melilotus) sainfoin (Onobrychis) , serradella (Ornithopus), cowpea (Vigna) 



FIG. 76. Pistil of flower of common bean (Phaseolus vulgaris). (Robbins after Knuth.) 



Timber Trees. The trees of the family useful for timber and structural 

 wood are logwood (H&matoxylon campechianum) , black locust (Robinia 

 pseudacacia) , mesquite (Prosopis juliflora), rosewood (Dalbergia latifolia) 

 and others. The plants, which are capable of producing commercial 

 fibers, are Crotalaria juncea, Sesbania cannabina, S. esculenta, Aeschyno- 

 mene spinulosa, Erythrina suberosa, etc. A considerable number of 

 plants yield gums, such as, copaiva balsams (Copaifera), balsam of 

 tolu (Tolmfera), copal (Hymenaa), gum arabic (Acacia), gum kino 

 (Pterocarpus) . As dye-yielding plants may be mentioned species of 

 Genista (yellow), Indigofera (blue), Mucuna pruriens, (black), H&ma- 

 toxylon (purple). 



