53 2 FLORA. 



flower; flowers about 2.5 cm. broad, the sepals purple within, pubescent without; 

 claws of the 3 upper petals united; stamens 4; fruit globose, pubescent, very spiny, 

 about 1.2 cm. in diameter. Fla. to Kans., N, Mex. and Mex. April-June. 



Family 17. PAPILIONACEAE L. 

 Pea Family. 



Herbs, shrubs, vines or trees, with alternate mostly compound stipu- 

 late leaves, and irregular (papilionaceous) perfect or sometimes polygamo- 

 dioecious flowers, mainly in spikes, heads, racemes or panicles. Calyx 

 4-5-toothed, or 4-5-cleft, sometimes 2-lipped. Petals more or less 

 united, or separate, perigynous or hypogynous, usually consisting of a 

 broad upper one (standard, banner), two lateral ones (wings), and two 

 front ones more or less united (forming the keel) ; the standard encloses 

 the wings in the bud. Stamens monadelphous, diadelphous, or sometimes 

 separate, 10 in most of the genera, sometimes 9, rarely 5. Pistil simple, 

 superior ; ovary mainly i -celled, sometimes 2-celled by the intrusion of the 

 sutures, or several-celled by cross-partitions ; style simple ; ovules i-many, 

 anatropous or amphitropous. Fruit a legume, i -many-seeded, dehiscent 

 into 2 valves, or indehiscent, in one tribe a loment. Seeds mostly with- 

 out endosperm ; cotyledons thick. About 320 genera and 5000 species, 

 most abundant in temperate and warm regions. 



* The 10 stamens distinct. 



Leaves pinnate. Tribe i. SOPHOREAE. 



Leaves digitate (in ours 3-foliolate), or simple. Tribe 2. PODALYRIEAE. 



" The stamens monadelphous or diadelphons. 

 Herbs, shrubs, woody vines or trees, the leaves not tendril-bearing. 

 Pod not a loment, 2-valved or indehiscent. 



Foliage not glandular-dotted (except in Glycyrrhiza, which has many-seeded 

 pods). 



Stamens monadelphous ; anthers of 2 kinds. Tribe 3. GENISTEAE. 



Stamens diadelphous (except in Ononis) ; anthers all alike. 

 Leaves, in our species, 3-foliolate, rarely i-foliolate. 



Leaflets denticulate. Tribe 4. TRIFOLIEAE. 



Leaflets entire. Tribe 5. LOTEAE. 



Leaves pinnately several-many-foliolate (3-foliolate in Orophaca), very 



rarely i-foliolate. Tribe 7. GALEGEAE. 



Foliage glandular-dotted ; pod indehiscent, i-2-seeded ; herbs. 



Tribe 6. PSORALEAE. 



Pod a loment ; herbs. Tribe 8. HEDYSAREAE. 



Herbaceous vines, or herbs ; leaves evenly pinnate, with tendrils. 



Tribe 9. VICIEAE. 



Vines, ours herbaceous, or erect herbs ; leaves odd-pinnate, mostly 3-foliolate, without 

 tendrils. Tribe 10. PHASEOLEAE. 



Tribe i. SOPHOREAE. 



Our species herbs ; flowers racemed. i. Sophora. 



Trees ; flowers panicled. 2 . Cladrastis. 



Tribe 2. PODALYRIEAE. 



Ovary sessile, or nearly so; pod flat in our species. 3. Thermopsis. 



Ovary distinctly stipitate; pod inflated. 4. Baptisia. 



Tribe 3. GENISTEAE. 



Herbs, with simple or 5-n-foliolate leaves. 



Leaves simple: pod inflated. 5< Crotalarta. 



Leaves 5-1 i-foliolate; pod flattened. 6. Lupinus. 



Shrubs, with i-3-foliolate leaves. 



Calyx divided into 2 lips ; leaves very prickly. 7. Ulex. 



Calyx cleft into 2 lips to about the middle. 



Calyx-teeth long. 8 . Genista. 



Calyx-teeth short. g . Cytisus. 



