Lbguminosae 583 



Leaves bipinnate; leaflets minute, about 1 mm long; flowers small, whitish; 



pods about 1 cm long, strongly curved 3450. Desmanthus, p. 585. 



Leaves pinnate; leaflets larger, more than 5 mm long; flowers yellow; pods not 



strongly curved, more than 1 cm long 3536. Cassia, p. 586. 



Trees. 



Leaflets ovate, acute or acuminate; unarmed, dioecious trees; flowers in long, 

 many-flowered racemes, about 1.5 cm long, pinkish white; pods 1-2 dm 



long, the valves very thick and woody 3545. Gymnocladus, p. 590. 



Leaflets oblong-lanceolate or oval, obtuse at the apex; trees armed with long 

 thorns (unarmed in one rare variety) ; flowers polygamous, minute, in 

 short, axillary spikes, greenish yellow; pods 3-40 cm long, 1-many-seeded, 



the valves not thick and woody 3544. Gleditsia, p. 589. 



Leaves even-pinnate or bifoliolate, the rachis prolonged into a tendril, rarely the 

 prolongation reduced to less than 1 cm long. 



Styles terete, bearded only at the summit; wings and keel usually adherent 



3852. Vicia, p. 616. 



Styles flattened, bearded along the inner face (this feature best observed in 

 unexpanded flowers); wings of flowers usually free. .3854. Lathyrus, p. 617. 

 A. Leaves odd-pinnate. 



Trees with 7-11 leaflets; terminal leaflets usually 6-9 cm wide; flowers in large 

 panicles 2.5-5 dm long; pods glabrous, 4-8 cm long. .3606. Cladrastis, p. 591. 

 Trees, shrubs or herbs not as above; terminal leaflets less than 6 cm wide. 

 B. Leaves mostly trifoliolate, or digitately 3-11-foliolate. 



Stamens 10, distinct; leaflets entire; flowers large; pods inflated, generally 



1-5 cm long 3618. Baptisia, p. 591. 



Stamens 10, monadelphous or diadelphous (9 and 1) ; pods not inflated. 

 Leaves glandular-dotted above or beneath. 



Peduncle 1-flowered ; pods not wrinkled, usually 4-7-seeded 



3696. Hosackia, p. 597. 



Peduncle many-flowered; pods wrinkled, 1-seeded. .3703. Psoralea, p. 597. 

 Leaves not glandular-dotted; pods not wrinkled. 



C. Leaflets serrulate; pods 1-6-seeded, small, indehiscent or tardily de- 

 hiscent. (The clovers, melilots, alfalfa, and medic.) 

 Pods curved or coiled; flowers in racemes, spikes or heads, yellow or 



purplish; stamens free from the corolla 3688. Medicago, p. 593. 



Pods straight. 



Inflorescence a head or spikelike; stamens adhering to the corolla. 



(The clovers.) 3690. Trifolium, p. 595. 



Inflorescence a raceme, white or yellow; stamens free from the 



corolla. (The melilots.) 3689. Melilotus, p. 594. 



C. Leaflets entire. 



Leaflets digitately 7-11-foliolate 3672. Lupinus, p. 593. 



Leaflets pinnately 3-foliolate. 



Fruit a flat, 1-7-jointed pod, at maturity separating into as many 

 segments as there are seed in the pod, the segments rounded 

 above and below or the lower part angular; surface of segments 

 densely pubescent, each hair ending in a minute hook; flowers 

 purplish or white, never bright yellow; leaflets generally stipel- 



late . 3807. Desmodium, p. 603. 



Fruit not as above. 

 Leaflets not stipellate. 

 Pods 1-seeded. 



Flowers bright yellow; pods 1- or 2-jointed, ribbed lengthwise, 

 thick, coriaceous, not symmetrical, the lower joint empty; 

 leaflets mostly 3-8 mm wide. .3802. Stylosanthes, p. 603 



