3(2). Flowers in open terminal racemes, usually deep-orange-yellow and brown- 

 ish; petals 4 mm. wide or more 4. Hoffmanseggia 



3. Flowers in dense globose heads or in axillary spikes; petals 2 mm. wide or 



less (4) 



4(3). Large spiny tree; flowers in spikes usually more than 4 cm. long 



3. Gleditsia 



4. Prostrate or clambering viny plants; flowers in globose or ellipsoid heads (5) 



5(4). Flower heads yellowish; roots orange-color; fruits abruptly narrowed at 

 the base to form a distinct stipe; plants unarmed 2. Neptunia 



5. Flower heads white or pinkish; roots not orange-color; plants either armed 



and clambering or unarmed and prostrate 1. Mimosa 



6(2). Leaves (most of them) with 4 or more leaflets (7) 



6. Leaves with 2 or 3 leaflets (23) 



7(6). Perennial or annual herbs or herbaceous vines, the aerial stems dying 

 back each winter, any new stems arising from the previous year's 

 root or underground stem (8) 



7. Shrubs, trees or woody vines, the stems of most of them persisting to produce 



new growth each year (21) 



8(7). Leaves palmate 5. Lupinus 



8. Leaves (most of them) pinnate, the leaflets arranged alternately or opposite 



on the rachis (9) 



9(8). Leaves gland-dotted; fruit a prickly pod 1-2 cm. long 15. Glycyrrhiza 



9. Leaves not gland-dotted; fruit smooth, not prickly ( 10) 



10(9). Leaves with an even number of leaflets or bearing tendrils toward the end 

 of the leaves; leaf rachis not terminated by a leaflet (11) 



10. Leaves not bearing tendrils and having an odd number of leaflets; leaf rachis 



terminated by a leaflet (13) 



11(10). Stems stiflly erect, 4—20 dm. tall; leaves without tendrils; leaflets 20 

 to numerous; flowers yellow, red or orange-color 12. Sesbania 



11. Stems weak, ascending or climbing by tendrils; leaflets less than 20; flowers 



blue, violet or purplish (12) 



12(11). Style with a dense ring of hairs just below the stigma 19. Vicia 



12. Style flattened, with a line of hairs down the inner surface 20. Lathyrus 



13(10). Rachis of leaf 2-15 (-20) mm. long; flowers 1 to 3 (or 4), terminal 

 on slender peduncles, never racemose along a central axis; leaflets 

 3 to 9 (14) 



13. Rachis of leaf 15-150 mm. long or (if shorter) then the flowers in several- 



flowered racemes; leaflets 5 to numerous (15) 



14(13). Stems and leaves appressed-pubescent or glabrate 9. Lotus 



14. Stems and leaves densely pubescent with wide-spreading glandular hairs 



17. Aeschynomene 



15(13). Fruit a loment, indehiscent, breaking into 1 -seeded segments at maturity; 

 stems stifily erect, to 25 dm. tall; flowers 1 to 4 in axillary fascicu- 

 late clusters, short racemes or solitary 17. Aeschynomene 



15. Fruits dehiscent or indehiscent but not breaking up into 1 -seeded segments 



at maturity; stems mostly 4 dm. long or shorter, but if longer and 

 stiffly erect then the flowers numerous in each raceme (16) 



16(15). Plants perennial; stems erect or high-twining, 3-20 dm. long; legume 

 6 to 20 times as long as broad, not inflated (17) 



1040 



