1138 



ERYNGIUM 



ERYNGIUM 



yolucre. The stiff leaves of the pandanus group are 

 little damaged by weather. The dried stems retain their 

 color, and are sometimes hung in living-rooms. The 

 plants mostly grow from 2 to 3 feet high and head out in 

 July to September. A light rich soil and sunny situa- 

 tion are advised. Poor drainage is to be avoided. E. 

 amethystinum is probably the most popular species in 

 this country. E. planum is said to be much visited by 

 bees. They are slow to recover from the shock of divi- 

 sion. This makes it diffi- 

 cult to work up a stock 

 at home sufficient to 

 make an effective group. 

 The only safe way to 

 increase them is by seed. 

 The seed may be sown 

 as soon as gathered. 

 They will germinate in 

 the spring, and should 

 be ready to plant out 

 the following year. Some 

 of the species self -sow. The species 

 described below are perennial. 



INDEX. 



A. The pandanus-leaved group. 

 B. Bracts of involucre long and prominent. 



1. agavifolium, Griseb. Becoming 6 ft. 

 high in its native country: st. simple below 

 and somewhat branched above, 3-forked at 

 top: basal Ivs. rosulate, ensiform, to 5 ft. 

 long, coarsely spinose-serrate: head cylin- 

 drical, about 2 in. long and half as thick; 

 the involucral bracts 10-16, ovate at base 

 and gradually narrowed, entire or sparsely 

 spinulose; sepals round-ovate or nearly- 

 orbicular; petals pbovate or elliptic-oblong. 

 Argentina, blooming Jan.-March. G.W. 15, p. 477. 



2. bromeliaefolium, Delar. Becoming 9 or 10 ft. 

 tall, the st. about 4-forked at top: basal Ivs. numerous, 

 1H ft. and more long, narrow and very acute, the 

 margins subulate-dentate, spine-pointed: head ovoid 

 or ovoid-cylindrical, about 1 in. long; involucral bracts 

 many, rigid, unequal, linear-subulate, pungent-pointed; 

 sepals ovate-lanceolate, short-acuminate and mucro- 

 nate. Highlands, Mex.; Dec. 



3. protaefldrum, Delar. Plant very stout, 3 ft. and 

 more, the st. fistulose and sulcate: st.-lvs. very stiff, 

 the upper ones 8 in. or more long, linear-lanceolate, 

 long-acuminate and pungent-pointed, the margin 

 subulate-spinose: head ovoid-cylindrical, 2J^ in. long; 

 bracts of involucre very many and very rigid, in several 

 series, lanceolate and sharp-pointed; fls. very many; 

 sepals broad-ovate, obtuse, short-mucronate; petals 

 white, obovate-spatulate. Mex. Sept. G.C. III. 

 41:248,249. Gn. 75, p. 380. 



BB. Bracts of involucre scarcely prominent, not very stiff. 

 c. Nerves of If. diverging. 



4. aquaticum, Linn. (E. yuccsefblium, Michx.). BUT- 

 TON SNAKEROOT. RATTLESNAKE MASTER. Height 



1417. Eryngium 

 amethystinum. ( X 1 A) 



2-6 ft.: st. striate, unbranched or branched above: 

 Ivs. undivided, long and linear, rigid, mostly clasping, 

 finely parallel-veined, lower sometimes 3 ft. long, 1J^ 

 in. wide, all bristly margined: heads globose-ovoid. 

 Wet soil, E. U. S. * 



cc. Nerves of If. parallel, prominent. 

 5. Lassauxii, Decne. Height 3-6 ft., thest. fistulose, 

 3-forked at top: basal Ivs. often slightly twisted, cana- 

 liculate, to 2 in. wide, long-acuminate, the margin 

 spiny: heads in a broad corymb, each one small, 

 about M m - through, whitish green; involucre-bracts 

 ovate- lanceolate, spinulose - ciliate ; 

 sepals nearly orbicular or 4-angled- 

 orbicular, truncate and erose; petals 

 rectangular-ovate. S. Brazil, Para- 

 guay, Uruguay. G.W. 3, p. 549. 



6. pandanifolium, Cham. & 

 Schlecht. St. to 8 ft. high, leafy, 

 3-4-forked above: basal Ivs. 4-5 ft. 

 long, spine margined above; st.-lvs. 

 many, to 1>2 ft. long, spiny; heads 

 colored, globose-ovoid, less than 

 ^2 in. long, in large panicles; invo- 

 lucral bracts broad-ovate, very 

 acute, rough on the back; sepals 

 nearly orbicular or oval, short- 

 mucronate; petals dark purple, 

 ovate or orbicular-oblong. S. Brazil, 

 Argentina. Gn. 61, p. 37. G.W. 4, 

 p. 197. 



7. eburneum, Decne. (E. bracted- 

 sum, Griseb.). Height 8 ft., from -a 

 thick rhizome, the st. ivory-white: 

 basal Ivs. crowded, canaliculate, 3 

 ft. and more long, acuminate, very 

 spiny, the spines being slender: 

 heads not colored, ovoid or globose- 

 ovoid, %in. long; involucral bracts 

 triangular or lanceolate or linear; 

 sepals ovate or oval, obtuse or 

 short-acuminate; petals somewhat 

 rectangular - oblong, fimbriate at 

 apex. S. Brazil, Uruguay, Argentina. 



AA. The cut-lvd. group (or Ivs., at least on st , 

 broader, more or less toothed, and not pan- 

 danus-like) . 



B. Lvs. fleshy. 



8. maritimum, Linn. Glaucous-blue, stiff, 

 much-branched, about 1 ft. high: Ivs. very stiff, 

 broad, sinuate, more or Iess3-lobed, handsomely veined, 

 with coarse prickly teeth, those on the st. clasping, 

 the radical ones petioled: heads nearly globular, pale 

 blue; involucral bracts 5-8, much smaller and narrower 

 than the st.-lvs.; sepals ovate-lanceolate; petals oblong. 

 Seacoasts of Eu. Gn. W. 15:489. 



BB. Lvs. not fleshy. 

 c. Basal Ivs. usually not lobed (or not prominently so}. 



9. alpinum, Linn. Height 12 ft., bluish above, from 

 a thick root: radical Ivs. deeply cordate-triangular, 

 acuminate, coarsely double-crenate; st.-lvs. round- 

 cordate, often 3-lobed at the apex or palmatifid: head 

 globose-cylindrical, about 1 in. long; involucral bracts 

 12-18, lance-oblong, rigid, multifid; fl?. many; sepals 

 ovate-lanceolate; petals somewhat rectangular. Eu. 

 B.M. 922. G.C. III. 53:139. G.M. 46:136. Gn.W. 

 21:278. G.W. 3:576; 15, p. 478. R.H. 1876, p. 113. 

 Gn. 46:523. There is a white variety. Prized for the 

 attractive blue color of the heads and upper part of 

 the plant. 



10. Oliverianum, Delar. (E. alpinum var. Oliver- 

 ianum, Spreng.). Hybrid, perhaps of E. planum and 

 E. giganteum, or perhaps with E. alpinum: plant strong, 



