Vernonia greggii subsp. schaffneri (A. Gray) G. C. Chapman & S. B. Jones

Vernonia schaffneri A. Gray, Proc. Am. Acad 17: 204. 1882. Stems erect, simple to the inflorescence, 3-7 dm. high, glabrous below, pubescent above; leaves numerous, the blades thin, bright-green, obovate, oblong, or broadly elliptic, 5-8 cm. long, 2-3.5 cm. wide, obtuse, entire, or serrulate toward the apex, tapering to a sessile base, papillose-scabrellate above, glabrous and pitted on the surface beneath, pubescent on the prominent reticulate veins; upper leaves but little smaller; inflorescence open, flattened, 1 dm. wide; heads about 40-flowered; involucre campanulate-hemispheric, 7-8 mm. high; scales purple, appressed, regularly and closely imbricate, glabrous or minutly ciliate, the outer lanceolate, acute, the inner oblong-lanceolate, obtuse; achenes puberulent, resinous in the furrows, 3 mm. long; pappus tawny, the bristles 6 mm. long, the scales narrowly linear, 1.1-1.3 mm. long, Type locality: Mountains near Morales, San Luis Potosi. Distribution: San Luis Potosi and Hidalgo.