522 



UMBELUFEREAE. 



[VOL. II. 



i. Eryngium aquaticum L,. Rattlesnake- 

 master. Button Snakeroot. (Fig. 2660.) 



Eryngium aquaticum L. Sp. PI. 232. 1753. 

 Eryngium yuccaefolium Michx. Fl. Bor. Am. i: 164. 

 1803. 



Stout, 2-6 high, glabrous; stem striate, simple, 

 or branched above. Leaves elongated-linear, acum- 

 inate at the apex, mostly clasping at the base, 

 finely parallel-veined, the lower sometimes 3 long 

 and i %' wide, the upper smaller, all with bristly 

 margins; heads stout-peduncled, globose-ovoid, 

 6 // -io // long, longer than the ovate or lanceolate 

 cuspidate bracts; bractlets similar to the bracts but 

 smaller; calyx-lobes ovate, acute; fruit scaly, about 

 \" long. 



In wet soil or upland, pine-barrens of New Jersey to 

 Illinois and Minnesota, south to Florida, Missouri and 

 Texas. June-Sept. 



2. Eryngium Virginianum Lam. 

 Virginian Eryngo. (Fig. 2661.) 



E. Virginianum Lam. Encycl. 4: 759. 1797. 



Stem slender, erect, glabrous, branched 

 above, striate, i-3 high. Upper stem- 

 leaves linear, acuminate, sessile and clasp- 

 ing at the base, a'-S' long, spiny-toothed 

 or rarely laciniate, reticulate-veined; basal 

 and lower leaves long-petioled, the blade 

 linear-oblong, often obtuse, entire, or re- 

 motely denticulate; heads subglobose, 4"- 

 7" long, equalling or shorter than the lan- 

 ceolate spiny-toothed or entire reflexed 

 bracts; bractlets usually j-cuspidate with 

 the middle cusp longest; calyx-lobes lan- 

 ceolate, cuspidate; fruit scaly. 



In marshes near the coast, New Jersey to 

 Florida, west to Texas. July-Sept. 





3. Eryngium Leavenworthii T. & G. 

 Lea vemvorth's Eryngo. (Fig. 2662.) 



Eryngium Leavenworthii T. & G. Fl. N. A. 1:604. 



!-(' 



Stout, glabrous, i-3 high, branched above. 

 Stem-leaves sessile, or somewhat clasping at the 

 base, palmately pinnatifid into narrow spiny- 

 toothed segments; basal and lowest leaves ob- 

 lanceolate, mostly obtuse, spinose-denticulate; 

 heads peduncled, ovoid-oblong, z'-z' long, 

 nearly i' thick, equalling or longer than the 

 spinose bracts; bractlets 3~7-cuspidate, those of 

 the upper part of the heads large and resem- 

 bling the bracts; calyx-lobes pinnatifid, longer 

 than the fruit. 



In dry soil, Kansas, to Texas. July-Oct. 



