Porophyllum nelsonii B. L. Rob. & Greenm.

Porophyllum guatemalense Rydberg, sp. nov
A slender shrub; branches purplish-brown, terete, striate; leaves opposite, short-petioled; blades thick, narrowly oblanceolate, 1-3 cm. long, with 1 or 2 large oblong glands on each margin and one at the apex; heads many-flowered, cymose; peduncles 1-4 cm. long; involucre campanulate, about 1 cm. high, purple; bracts 5, oblong, acute, round-keeled and somewhat gibbous below; glands linear, in two rows; corollas purplish, 7-8 mm. long; tube much longer than the funnelform throat; lobes lanceolate; achenes dark, 6-7 mm. long, hispidulous; pappus 7 mm. long, tinged with purple.
Type collected near Newton, Guatemala, 1895, E. W. Nelson 3523 (U. S. Nat. Herb.).

Porophyllum nelsonii Rob. & Greenm. Proc. Am. Acad. 32: 32 1896.
A branching shrub, 3-6 dm. high; branches terete, purple; leaves opposite; petioles 4-6 mm. long; blades small, oblong or elliptic, obtuse, 1-1.5 cm. long, about 0.5 cm. wide, tapering at the base, with 0-2 marginal glands on each side and a single terminal one; heads cymosecorymbose; involucre narrowly campanulate, about 1 cm. high; bracts 5, linear-oblong, acute, purple, with 2 rows of linear glands; flowers about 30; corollas dark-purple, about 7 mm. long; tube puberulent, fully twice as long as the elongate-funnelform throat; achenes 6-7 mm. long, hispidulous, tapering at the apex.
Type i.ocality: Between Panixtlahuaca and Jaqulla, Oaxaca. Distribution; Oaxaca.