96 DIADELPHIA. DECANDKIA. 



IIa-b. On sand-hills, on the bahks of the Missouri, not tar 

 from the confluence af the river Platte. Flowerin.^ in May. 

 jPsoralca longifolin Ph. 2. suppl. p. 741. See Herb. Lam- 

 {Tcrt. Or.s. Roots perennia', filiform, creeping. Stems nearly- 

 simple, terete below and ang-vilar above. Stipules con- 

 nate, distinct from the petioles, ovate, acute, below lan- 

 ceolate, acuminate above. Leaves singularly elongated, 

 much like those of Indigofera JilifolUi of the Cape of Good 

 Hope; the lowest shortest, often trifoliate, above they are 

 sometimes bjugate (or in 5's), the uppermost simple, 

 scarcely a line wide, and nearly a span long. Racemes 1 

 or 2 m the same axill, 7 to lO-fiowered; flowers somewhat 

 remote, pale red, nearly as large, but shorter, than 

 those of O. sijlvaticna; calix and bractes subulate. Vexil- 

 lum rallier broad, stamina diudelphous. Style and minute 

 subcapitate stigma smooth. Legume linear-lanceolate, 

 exserted, flatly compressed, smooth, 8 to 10-seeded. 

 Certainly a very exti-aordinary species of Orobusy yet in- 

 separable in genus from the preceding; both these spe- 

 cies appear to be somewhat allied to Tephrosia, but the 

 stamina are diadelphous, and the whole habit and fruit is 

 different from the American species of that genus. 



Orobus is principally an European genus extending, 

 however, into Siberia and Northern Africa; 0. fmticosus 

 of Peru IS scarcely a congener. 



496. LATHYRUS. L, (Vetchling, Everlasting 

 Pea.) 

 SUjle flat, broader above and villous on the 

 upper side. The upper segments of the calix 

 shorter. 



An heteroraorphous and unnatural genus, scarcely dis- 

 tinct from many European species of the preceding. — 

 .Stems scandent or diffuse, with the angles often alated 

 by the decurrence of the petioles; stipules cauline, dis- 

 tinct, usually toothed or produced at the base; leaves 

 pseudopinnate, from 1 to 5 pair, (m L. JSt'issolia simple, 

 and m L. Aphaca altogether abortive,) common petiole as 

 in the Pea terminating in a divided tendril; peduncles ax- 

 illary and terminal, 1, 2, and many-flowered. 



Species. 1. L.pahistHs. 2. myrtifolius. Near Philadel- 

 phia, o.venosus' Leaflets about 5 pair. Common in the Al- 

 leghany mountains, growmg on the declivities of shady 

 hills. 



4. * polyynorphus. Stem quadrangular, naked; stipules 

 semisagittate, lanceolate; leaflets 4 to 5 pair, linear-oblong, 



