1290 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



Leaves hastate-lobate at base. 



Corolla 5-parted 29. S. triquetnim. 



Corolla 5-angulate 30. S. xanti. 



Leaves not hastate-lobate. 



Anthers linear, about 3 times as long as broad; leaves glabrous 



beneath except along the costa 12. S. jasminoides. 



Anthers broadly oblong or oval, less than twice as long as broad; 



leaves short-villous beneath 13. S. macrantherum. 



Leaves all pinnate or pinnate-lobate. 

 Pubescence of fine branched hairs; lobes of the leaves obtuse. 



14. S. palmeri. 

 Pubescence of simple hairs; leaf segments acute or acuminate. 



Corolla about 5 mm. long 15. S. appendiculatum. 



Corolla about 10 mm. long. 



Leaves glabrous beneath 16. S. seaforthianiun. 



Leaves villosulous beneath 17. S. galeotti. 



BB. Leaves simple, entire or toothed, never hastate-lobate; plants com- 

 monly erect. 

 C. Mature leaves densely stellate-pubescent beneath over the whole 

 surface. 

 Flowers in few-flowered lateral umbels. 



Corolla lobes ascending 18. S. lignescens. 



Corolla lobes reflexed. 

 Hairs on the upper surface of the leaves mostly simple. 



19. S. plurifurcipilum. 

 Hairs on the upper surface of the leaves all branched. 



20. S. jaliscanum. 

 Flowers in many-flowered cymes, these often terminal. 

 Younger branches with coarse, conspicuously stipitate, branched 



hairs 21. S. umbellatum. 



Younger branches with fine stellate hairs, these sessile or nearly so. 

 Leaves glabrous on the upper surface or nearly so, attenuate at 



base 27. S. cervantesii. 



Leaves densely stellate-pubescent on the upper surface or, if gla- 

 brate, obtuse or rounded at base. 

 Petioles very short, less than 1 cm. long; calyx shallowly and 



obtusely denticulate 22. S. salviifolium. 



Petioles usually more than 1 cm. long; calyx deeply dentate. 

 Ovary tomentose ; leaves velutinous-tomentose on the upper 



surface 23. S. verbascifolium. 



Ovary glabrous; leaves stellate-scaberulous on the upper sur- 

 face or glabrate. 

 Hairs on the lower surface of the leaf extremely minute, 



the leaves appearing glabrous 24. S. plumense. 



Hairs on the lower surface of the leaf conspicuous. 



25. S. bicolor. 

 CC. Mature leaves glabrous beneath or nearly so, the pubescence, if any, 

 chiefly along or near the costa, or the leaves sometimes rather dense- 

 ly pubescent with simple hairs. 

 Flowers in large many-flowered cymes, these chiefly terminal. 



Branches winged 26. S. aligerum. 



Branches not winged 27. S. cervantesii. 



