126 American Midland Naturalist Monograph No. 7 



ous; woods and thickets, extending southward to Christian 

 and Madison counties. May. Common Cliokecherry. The 

 fonn with the lower surface of the leaves, young twigs, 

 and rachis of inflorescence pubescent is f. deamii G. N. 



Jones P. virginiana L. 



12. Leaves firm, oval or lanceolate, crenulate-sen-ate with in- 

 cui^ved teeth; sepals obscurely glandular, persistent; woods 

 and along fences, common throughout 111. May. Wild 

 Black Cherry P. serotina Ehrh. 



54. Leguminosae P.F.Gmel. — Pea Family 

 1 . Trees or shrubs. 



2. Leaves simple, entire, suborbicular to reniform: flowers pink, perfect, in 

 sessile umbels, appearing before the leaves; pods 6-8 cm long, pointed 



at each end 3. Cercis 



2. Leaves compound. 

 3. Erect shrubs or trees. 



4. Shrubs: flowers in racemes. 



5. Twigs and petioles hispid; petals 5; pods linear, hispid, several- 

 seeded 21. Robinia 



5. Twigs and petioles not hispid; corolla of one purple petal; pods 



short, 1- to 2-seeded 17. Amorpha 



4. Trees; petals 5. 



6. Leaves odd-pinnate, with 5-17 leaflets: flowers white. 1-2.5 cm 



long. 

 7. Stipules spiny, woody: stipels setaceous; bark rough; stamens 

 diadelphous; racemes 7-15 cm long 21. Robinia 



7. Stipules and stipels none; bark smooth; wood yellow; stamens 



distinct; inflorescence 15-50 cm long 7. Cladrastis 



6. Leaves 1- to 2-pinnate. 



8. Leaflets ov-ate, entire, acute or acuminate; flowers pinkish- 



white, 1.5 cm long, in many-flowered racemes; pods woody; 



trees without spines 4. Gymnocladus 



8. Leaflets oval or lanceolate, remotely denticulate, obtuse; flowers 

 small, greenish-yellow, in axillary spikes: pods leathery; 



trees usually with spines on the trunk and branches 



5. Gleditsia 



3. Twining shrubs, not prickly: flowers purple, showy, racemose: petals 



5; leaflets 9-13; pods many-seeded 22. Wisteria 



1. Herbs. 



9. Leaves simple; petals yellow 9. Crotalaria 



9. Leaves compound (rarely 1-foliolate) . 



10. Leaves even-pinnate (or bipinnate), or leaflets only 2. 

 11. Leaves ending in a tendril; flowers papilionaceous. 



12. Style terete, pubescent near the apex 30. Vicia 



12. Style flattened, pubescent along the inner side 31. Lathyrus 



11. Leaves not ending in a tendril; leaflets numerous, small; flowers 



not at all papilionaceous, in globose heads. 



13. Leaves bipinnate. 



14. Plants glabrous or nearly so: flowers greenish-white; petals 



distinct or nearly so; pods flat, smooth 1. Desmanthus 



