VMBELLIFEKAE. 673 



2. Sanicula gregaria Bicknell. Clustered Snake-root. (I. F. f. 26C5.) 

 Stems erect, 3-9 dm. high, umbellate-branched, the branches slender. Leaves 

 thin, bright green, 5 -divided; segments stalked, obovate-cuneate to lanceolate, acute 

 or acuminate, doubly serrate with bristle-tipped teeth, sharply incised, mostly less 

 than 8 cm. long; basal leaves numerous, those of the stem only I or 2, petioled; in- 

 volucral leaves large. 3-parted; pedicels of staminate flowers, 2-3 mm. long, 3 or 4 

 times the length of the minute campanulate calyx; calyx-lobes ovate, obtuse; petals 

 much surpassing the calyx; fruit stipitate, broadly obovoid, 3 mm. long, the 

 slender styles recurved; bristles very small; oil-tubes 5; seed not furrowed. In 

 woods and thickets, Vt. and Ont. to Minn., Va., Kans. and Neb. May-June. 



3. Sanicula Canadensis L. Short-styled Snake-root. (I. F. f. 2666.) 

 Rather dull green. 3-12 dm. high, widely branched, the umbellate fruit-bearing 

 rays only 2-10 mm. long. Stem leafy; leaves petioled, 3-5 -divided; segments 

 cuneate-obovate to narrowly oblong, acute, mucronate-serrate, or incised, often 

 small; involucral leaves small, those of the involucels bract-like; staminate flowers 

 few; calyx 1 mm. long, parted into linear-lanceolate acute lobes which exceed the 

 minute white petals; fruit short-stipitate, subglobose; the bristles slender; oil-tubes 

 5 ; seed dorsally furrowed. In woodlands, Vt. to Fla., S. Dak. and Tex. June- Aug. 



4. Sanicula trifoliata Bicknell. Large-fruited Snake-root. (I. F. f. 2667.) 

 Stem slender, 3-8 dm. high. Umbels of 3-5 often irregular rays 8-25 mm. long; 

 leaves rather bright green, thin, slender-petioled, 3-divided; segments stalked, 

 broadly ovate, or obovate, or the lateral ones rhomboid, acute, coarsely doubly ser- 

 rate, or incised, the teeth spinulose-cuspidate; staminate flowers few; calyx I mm. 

 long, its linear rigid lobes incurved, subulate; petals white, about half as long as 

 the calyx; larger oil-tubes 2, with numerous minute ones; seed not sulcate. In 

 hilly woods, Vt, to Ont., N. Y. and Ind. June-July. 



4. ERYNGIUM L. 



Herbs, with spiny-toothed lobed dentate or sometimes dissected, rarely entire 

 leaves, and bracted heads or spikes of small white or blue flowers subtended by 

 bractlets. Calyx-teeth rigid, pungent, or acute. Petals erect. Disk expanded. 

 Fruit scaly or tuberculate, somewhat flattened laterally. Carpels nearly terete, 

 their ribs obsolete or none, the oil-tubes usually 5. [Greek, a kind of thistle.] 

 About 150 species, of wide distribution. Besides the following, about 18 others 

 occur in southern and western N. Am. 



Plants erect, tall ; stem-leaves spiny or bristly-margined. 



Leaves elongated-linear, parallel-veined. 1. E. aquaticum. 



Leaves elongated-linear, reticulate-veined. 2. E. Virginiatium. 



Stem-leaves palmately incised-pinnatifid. 3. E. Leavenworthii. 



Plants prostrate, slender; leaves unarmed. 4. E. prostratu?n. 



I. Eryngium aquaticum L. Rattlesnake-master. Button Snake- 

 root. (I. F. f. 2660.) Stout, 6-18 dm. high, glabrous. Leaves acuminate, mostly 

 clasping at the base, the lower sometimes 1 m. long and 4 cm. wide; heads stout- 

 peduncled, globose-ovoid, 1-2 cm. long, longer than the ovate or lanceolate cuspi- 

 date bracts; calyx-lobes ovate, acute; fruit scaly, about 2 mm. long. In wet soil 

 or upland, Conn, to S. Dak., Fla., Kans. and Tex. June-Sept. 



2 Eryngium Virginianum Lam. Virginian Eryngo. (I. F. f. 2661.) 

 Stem glabrous, 3-9 dm. high. Upper stem-leaves linear, acuminate, sessile and 

 clasping at the base, 5-20 cm. long, rarely laciniate; basal and lower leaves long- 

 petioled, the blade linear-oblong, entire, or remotely denticulate; heads subglobose, 

 8-14 mm. long, equalling or shorter than the lanceolate reflexed bracts ; bractlets 

 usually 3-cuspidate; calyx-lobes lanceolate, cuspidate; fruit scaly. In marshes 

 near the coast, N. J. to Fla.. west to Tex. July-Sept. 



3. Eryngium Leavenworthii T. & G. Leavenworth's Eryngo. (I. F. 

 f. 2662.) Stout, glabrous, 3-9 dm. high. Stem-leaves sessile, palmately pinnati- 

 fid into spiny-toothed segments; basal and lowest leaves oblanceolate, mostlv ob- 

 tuse, spinose-denticulate; heads peduncled, ovoid-oblong, 2-5 cm. long, equalling 

 or longer than the spinose bracts; bractlets 3-7-cuspidate, those of the upper part 

 of the heads large and resembling the bracts; calyx-lobes pinnatifid. In dry soil, 

 Kans. to Tex. July-Oct. 



