Eryngium serratum Cav.

Eryngium serratum Cav. Anal. Hist. Nat. 2: 132. 1800
Eryngium Schiedeanum Schleeht. & Cham. Linnaea 5: 206. 1830.
Slender, caulescent, branching, glabrous perennials, 2-8 dm. high, from a fascicle of woody-fibrous roots; basal leaves coriaceous, lanceolate to oblong, 4-15 cm. long, 1-2 cm. broad, long-cuneate at the base, acute or obtuse at the apex, callous-margined, coarsely spinulose-serrate or spinulose-dentate to subpinnatifid, the venation pinnately reticulate; petioles narrowly winged, broadly sheathing at the base, 0.2-2 dm. long, shorter or longer than the blades; cauline leaves few, the upper greatly reduced, sessile, incised or lobed; inflorescence cymose, the heads few, pedunculate, rather large, the flowers numerous; heads greenish, subglobose to ovoid-cylindric, 5-IS mm. long, 6-12 mm. broad; bracts 8-12, foliaceous, rigid, ascending, linear-lanceolate, 5-10 mm. long, 1-2 mm. broad, acute or acuminate, entire or with 1 or 2 spinose teeth, greenish on both sides, shorter than the heads; bractlets subulate, 5-6 mm. long, narrowly scarious-winged at the base, exceeding the fruit; coma wanting; sepals narrowly lanceolate, 2—3 mm. long, mucronate, entire; petals oblong, 1.5-2 mm. long; styles slender, exceeding the sepals; fruit subglobose, 3-5 mm. long, densely covered with appressed, white, lanceolate-acuminate scales, the lateral and calycine larger than the dorsal.
Type locality: "Huanajuato [Guanajuato], Nuevo-Espafia [Mexico]," collector unknown. Distribution: Nuevo Leon and San Luis Potosi to Vera Cruz and Mexico (Pringle 3156,