862 AMMIACEAE 



involucres linear-lanceolate or linear-spatulate, reflexed at maturity, longer than the head : 

 fruit about 1 mm. long, sparingly tuberculate. 



In low grounds and pine lands, Kentucky to Missouri, Georgia, Florida and Texas. Summer. 



3. Eryngium Floridanum Coult. & Rose. Perennial. Stems 6-9 dm. tall, often 

 sparingly branched : leaf-blades various, those of the basal leaves narrowly oblong, 2.5-10 

 cm. long, usually entire, long-petioled, those of the upper stem-leaves long-linear, mostly 

 remotely serrulate, sessile or nearly so : heads subglobose, 10-12 mm. long : bracts of the in- 

 volucre linear-lanceolate, reflexed, longer than the head : bractlets linear, mucii longer than 

 the flowers, entire, sharp-pointed : fruit about 2 mm. long, crowned with the ovate acute 

 sepals. 



In brackish marshes. Florida. Spring to fall. 



4. Eryngium Virginianum Lam. Perennial. Stems 3-9 dm. tall, more or less cor- 

 ymbosely branched above : leaf-blades linear or oblong-lanceolate, 1-3 dm. long or longer, 

 serrate or laciniate above, acute, sessile or those of the lower cauline or basal-leaves undulate 

 and long-petioled : heads cylindric or oblong-ovoid, 1-1.5 cm. long, bur-like : bracts of the 

 involucre linear, entire or spiny-toothed, as long as the heads or longer : bractlets rigid, 

 3-pronged, the middle prong longer than the lateral : fruit scaly, crowned with the lan- 

 ceolate acuminate sepals. 



In swamps and on margins of ponds, New Jersey to Florida and Texas. Spring to fall. 



5. Eryngium Mettavieri Wood. Perennial, glabrous. Stems 10-18 dm. tall, sim- 

 ple or nearly so below : leaf-blades linear or linear-lanceolate, those of basal or lower stem- 

 leaves 1-2 dm. long, undulate, their petioles often 2-3 dm long, jointed, those of upper 

 stem-leaves attenuate, more or less spiny-toothed near the base : heads ovoid or globose- 

 ovoid, about 1.5 cm. long, robust: bracts of the involucres linear or narrowly linear-lan- 

 ceolate, .spiny-toothed, as long as the heads or longer, reflexed : bractlets with three equal 

 prongs : fruit about 2 mm. long, crowned with the ovate acute sepals. 



In low grounds, Florida. Summer and fall. 



6. Eryngium Ravenfelii A. Gray. Perennial. Stems 5-10 dm. tall, branched above : 

 leaf-blades linear, elongated, conduplicate, undulate or slightly toothed, those of basal and 

 lower stem-leaves 3-5 dm. long, those of the upper stem-leaves shorter : heads subglobose, 

 about 1 cm. long : bracts of the involucre spiny-toothed or entire, reflexed at maturity : 

 bractlets 3-pronged : fruit about 2 mm. long, crowned with the short mucronate sepals. 



In swampy pine lands, South Carolina to Florida. Summer and fall. 



7. Eryngium integrifolium Walt. Perennial. Stems 4-9 dm. tall branching above, 

 or sometimes also at the base : leaf-blades oblong to ovate-oblong or oblong-lanceolate, 3-8 

 cm. long, shallowly serrate or crenate, acute or obtuse, crenate or subcordate at the 

 base, all but the upper ones with broad petioles seldom over 1 cm. long : heads few, 8-10 

 mm. long, often broader than high : bracts of the involucres linear, entire or with few 

 spine-like teeth, longer than the head, spreading : bractlets 3-pronged, surpassing the flow- 

 ers : fruit over 2 mm. long, crowned with lanceolate acuminate sepals. [^E. virgatum Lam.] 



In pine woods, North Carolina to Florida and Texas. Summer and fall. 



8. Eryngium Ludovicianum Morong. Similar to E. integrifolium in habit, but more 

 slender : leaf-blades linear or linear-lanceolate, 2.5-7 cm. long, laciniately toothed at least 

 near the base : heads numerous, mostly less than 7 mm. long : bracts of the involucre very 

 narrowly linear or linear-flliform, commonly less than 1 cm. long: fruit less than 1.5 mm. 

 long, crowned with the triangular sepals. 



In thickets and low grounds, Louisiana and Texas. Summer and fall. 



9. Eryngium Hookeri Walp. Perennial. Stems 2-7 dm. tall, branching above: 

 leaf-blades various, those of basal leaves oblong or ovate-oblong, 3-6 cm. long, shallowly 

 toothed, their petioles shorter than the blades, those of the lower stem-leaves lanceolate, 

 laciniately-toothed and spinulose, with a pair of small laciniate segments at the base, sessile 

 or nearly so, those of upper leaves palmately 5-7-parted : heads ovoid-globose, 8-12 mm. 

 high : bi-acts of the involucres linear or linear-lanceolate, longer than the head, spiny- 

 toothed : bractlets entire, spine-tipped, the terminal ones elongated : fruit scaly, 1 mm. 

 long, crowned with the spine-tipped sepals. 



In low grounds, Texas. Spring and summer. 



10. Eryngium aromiticum Baldw. Perennial. Stems often branched at the base, 

 the branches ascending or prostrate, 1-6 dm. long, corymbosely branched near the top : 

 leaf-blades rigid, 1-3 cm. long, pinnately parted, the segments various, the lower setaceous, 

 the upper lanceolate to oblong or oval, spine-tipped and cartilaginous margined : heads sub- 

 globose, 5-10 mm. in diameter, bristly : bracts of the involucres 3-cleft,^ longer than the 

 head : bractlets 3-toothed : fruit 1 mm. long, tuberculate, crowned with the longer bristle- 

 like sepals. 



In dry pine lands, Florida and Alabama. Summer and fall. 



