Eryngium longifolium Cav.

Eryngium longifolium Cav. Anal. Hist. Nat. 2: 133. 1800
Eryngium Watsoni Coult. & Rose; Rose, Contr. U. S. Nat. Herb. 8: 334. 1905. Eryngium Langlassei H. Wolff, Repert. Sp. Nov. 9: 417. 1911.
Slender, caulescent perennials, 5-20 dm. high, from a short, oblique, tuberous rootstock bearing a fascicle of fibrous-fleshy roots, the stems solitary, erect, branching; basal leaves numerous, broadly linear, 3-7 dm. long, 1-2 cm. broad, broadest at the base, attenuate at the apex, weakly spinose-ciliate, the spines slender, ascending, the longest 2-6 mm. long, axillary spines minute or wanting, the venation parallel; sheaths broader than the blades, vaginate, 6-12 cm. long; cauline leaves few, like the basal, amplexicaul, alternate, ascending, the upper greatly reduced, opposite; inflorescence divaricately cymose, the heads rather large, numerous, pedunculate, the flowers numerous; heads globose-ovoid to ovoid-cylindric, S— 15 mm. long, 8-10 mm. broad, rounded at apex and base; bracts 6-8, rigid, spreading to loosely reflexed, linear-lanceolate, 3-12 mm. long, I mm. broad, pungent, entire, much shorter than the heads; bractlets narrowly lanceolate, 3-5 mm. long, pungent, entire, occasionally puberulent (?), slightly exceeding the fruit; coma wanting; sepals broadly ovate, 1 mm. long, obtuse, apiculate; petals oval, about 1 mm. long; styles slender, exceeding the sepals; fruit turbinate, 2-3 mm. long, the calycine and lateral scales lanceolate, up to 1 mm. long, the dorsal greatly reduced or obsolete.
Type locality: Between Pachuco and Real del Monte, Hidalgo, collector unknown. Distribution: Jalisco to Mexico and Guerrero (Mexia 9028, Pringle 6197).