112 LEGTTMINOS^E. 



ticulate. Flowers perfect, solitary, or several in a raceme, spike, head, or sometimes 

 panicle. 



Our 16 genera represent almost half as many tribes, corresponding to the principal divisions of 

 the following key. 



I. Stamens distinct. 



* Leaves digitately 3-foliolate. 



1 . Thermopsis. Herbs, with conspicuous stipules, and yellow flowers in racemes. 



2. Fickeringia. Shrub, with minute stipules or none, and purple solitary flowers. 



* * Leaves unequally pinnate : shrubby. 



3. Sophora. Pod thick, large, several-seeded, often transversely constricted : leaves coriaceous. 

 10. Amorpha. Pod small, 1 - 2-seeded. Petal one ! Stamens monadelphous at the very base. 



II. Stamens monadelphous, or diadelphous (9 and 1). 



* Anthers of two forms : filaments strictly monadelphous : leaves digitate, of more than 3 quite 



entire leaflets. 



4. Lupinus. Calyx deeply bilabiate. Standard with recurved sides : keel falcate. Pod large, 



straight. 



* * Anthers uniform. 



+- Leaflets 3, or rarely digitately 5 to 7, denticulate or serrulate : stamens diadelphous or nearly 

 so : pods small and enclosed in the calyx, or curved or coiled. 



5. Trifolium. Flowers capitate. Corolla persistent, united with the filaments. Pod small, 



mostly in the calyx. 



6. Melilotus. Flowers in axillary racemes or spikes, small. Petals free, deciduous. Style 



filiform. Pod small, wrinkled, globular. 



7. Medicago. Flowers nearly of Melilotus. Pod spirally coiled or curved. Style subulate. 



+- -i- Leaves unequally pinnate (very rarely digitate or simple) ; leaflets entire : no tendril. 

 ++ Flowers umbellate or solitary, on an axillary peduncle. 



8. Hosackia. Herbaceous or shrubby. Corolla yellow or partly white, or turning reddish : 



claw of the standard usually remote from the others. Pod linear, several-seeded. 



++ ++ Flowers in spikes, racemes, or heads, never umbellate. 

 = Herbage glandular-dotted : stamens mostly monadelphous. 



9. Psoralea. Herbs, with 3-foliolate leaves and axillary spikes. Stamens mostly monadel- 



phous. Pod indehiscent, one-seeded. Ovule solitary. 



10. Amorpha. Shrubs, with pinnate leaves and terminal or panieled racemes. "Wings and keel 



of the corolla wanting. Stamens monadelphous only at base, otherwise distinct. Pod 

 nearly indehiscent, 1 - 2-ovuled, 1 - 2-seeded. 



11. Dalea. Shrubby or herbaceous, with pinnate or simple leaves and terminal spikes or heads. 



Wings and keel inserted on. and articulated with the monadelphous stamen-tube. Pod 

 indehiscent, 2 - 6-ovuled, mostly one-seeded. 



= = Herbage glandular or glutinous and more or less punctate : leaves unequally pinnate : sta- 

 mens diadelphous ; anthers eonfluently 1-celled. 



12. Glycyrrhiza. Flowers, &c, of Astragalus. Pod prickly or muricate, short, 1-celled. 



= = = Herbage neither glandular nor dotted : stamens diadelphous ; anthers 2-celled : leaves 



pinnate. 



13. Astragalus. Herbs, unarmed. Pods mostly bladdery or turgid, or more or less 2-celled by 



intrusion of the dorsal suture. 

 11. Olneya. Tree, spinescent, nearly destitute of stipules. Pod 2-valved, several-ovuled, 1-2- 

 seeded ; valves very thick and firm. 



-f- +- +- Leaves abruptly pinnate, terminated by a tendril or bristle (occasionally by an imperfect 

 leaflet) : stamens diadelphous : peduncles axillary : pod 2-valved : seed-stalks broad or 

 expanded at the hilum : herbs. 



15. Vicia. Stamen-tube oblique at the summit. Style filiform, hairy around and below the 



apex. 



16. Lathyrus. Stamen-tube nearly truncate. Style dorsally flattened toward the apex, hairy 



on the inner side, usually twisted half round. 



