546 ERYNGIUM 



up in living-rooms. The plants mostly grow from 2-3 

 ft. high and head out in July and Sep. J. B. Keller ad- 

 vises a light soil and sunny situation. E. ainetlii/stinum 

 is probably the favorite. Meehan says that Ji, planum 

 is much visited by bees. The weak point of Eryngiums 

 is that they are slow to recover from the shock of divi- 

 sion. This makes it difficult to work up a stock at home 

 sufficient to make an effective group. D. Dewar, in his 

 garden monograph of the group, Gn. 46, p. 522, says that 

 the only safe way to increase the Sea Hollies is by seed. 

 "Sow the seed in pans as soon as gathered, and place in 

 a coldframe. The seeds will germinate in the spring, 

 and if properly managed will be ready to plant out the 

 following year." It is said that many of the species are 

 less showy and satisfactory here than in England. 

 A. I/vs. divided into radiating segments. 

 B. Bracts longer than the heads. 

 C. Number of bracts 10-SO. 

 D. Jioot-lvs. deeply notched at the base and merely 

 toothed at the margin. 



1. alplnum, Linn. Bracts 10-20, a little longer than the 

 oblong heads. Alps. R.H. 187G. p. 113. B.M. 922. (Sn. 

 46:993. — There is a white variety. 



DD. Boot-li'S. less deeply notched at the base, elsewhere 

 more dissected. 



2. Oliveri^num, Laroch. Bracts 10-12, more rigid and 

 fewer-toothed than in £. alpinum : heads ovate. 

 Orient. Gn. 45, p. 223. 



CO. Number of bracts 6-9. 

 D. Root-lvs. deeply cut. 



3. ameth^stinum, Linn. Fig. 776. Root-lvs. pinnatifid: 

 bracts 7-8, few-toothed at the base, much longer than 

 the globose heads. Eu. Gn. 46, p. 522, and 55, p. 454. E. 

 caelestinum, a trade name unknown to our botanies, is 

 the same thing, according to J. B. Keller. 



nn. Hoot-lvs. merely crenate-dentate. 



4. gigantdum, Bieb. Root-lvs. deeply cordate: bracts 

 8-9: head ovate. Armenia. Gn. 46, p. 523. 



BB. Bracts as long as or shorter than the heads. 

 c. Upper stem-li'S. 5-parted. 



5. pl&num, Linn. Middle stera-lvs. stalkles.s, undi- 

 vided: bracts 6-7: head rotund. Eu., N.Asia. 



cc. Upper stem-h'S. about 8-parted. 



6. L^avenworthii, Torr. & Gray. Height 1-3 ft. : stem- 

 Ivs. stalkless, somewhat clasping : heads ovoid-oblong. 

 Kans. to Tex., Mex. B.B. 2:522. 



AA. I/cs. undivided, long and linear. 



7. aqudticum, Linn. (A^. j/HCcopWJiHjH, Michx.). Height 

 2-6 ft.: stem striate, uribranched or branched above: 

 Ivs. mostly clasping, finely parallel-veined, lower some- 

 times 3 ft. long, 1% in. wide, all bristly margined: 

 heads globose-ovoid. U. S. B.R. 5:372. ^_ jj 



In No. 1 the involucre 

 is a deeper blue than 

 in Nos. 2-5 ; in No. 7 the 

 involucre is not colored 

 and the fls. are white 

 or pale. No. 1 needs 

 deep soil and partial 

 .shade. No. 3 also makes 

 a good bog plant. No. 

 7 grows well in either 

 wet or dry situations. 

 Heights of the first five 

 species, 2-3 ft.; 3-5, 

 2-3 H; 3^, .3-4. 



P. W. Barclay. 



ERYSIMUM (possi- 

 iily means blister-draw- 

 ing). Cruciferte. Of 

 this big genus we cul- 

 tivate two brilliant 

 yellow and orange, 

 spring- and summer- 

 blooming, hardy "an- 

 777 Erysimum aiperum nuals," scarcely, if at 



ERYSIMUM 



all, inferior to the true wallflowers (Cheiranthus) for 

 general purposes, and two lower-growing and perhaps 

 earlier-blooming rock-garden plants. The genus has 

 70-100 species of biennial and perennial herbs, with 

 long, soft, appressed, 2-parted hairs: Ivs. narrow, linear 

 or oblong, entire or variously toothed: fls. orange or 

 yellow, rarely purple, often fragrant ; petals 4 ; style 

 persistent. 



Although the two most popular kinds are biennials, 

 the gardeners think of them as annuals. Their seeds can 



778. Erysimum asperum (X3^). 



be sown in the fall and produce earlier bloom than if 

 sown in spring. Fig. 777 shows the last flowers open at 

 the top of the pyramid, while the seed pods are swelling 

 below. 



The rockery kinds, J. B. Keller writes, do well also in 

 the front row of the border and on dry banks. They like 

 full exposure to sunlight, and in the spring months are 

 completely covered with bright flowers, Divided plants 

 only, not seeds, are offered by American dealers. In 

 Gn. 24, p. 462, it is said that £!. ochroleucnm on level 

 ground is likely to lose its lower Ivs. and to perish on 

 heavy soils in hard winters. It thrives best when fre- 

 quently divided, and may be prop, by cuttings. 



A. Plants biennial: height 1£-1S in. 

 B. Fls. yellow. 



isperam, DC. (A'. Arkansdntitn, Nutt.). Figs. 777, 

 778. Height 1-3 ft. in the wild, 12-18 in. in gardens : Ivs. 

 dentate or entire, upper ones mostly entire: fls. H in. 

 across: pods rough, IJ2— 4in. long, 4-sided, nearly erect. 

 U. S. E. Arkansanum isinerely a western and broader- 

 leaved form. B.B. 2:152. 



BB. Fls. orange. 



Ferofski&num, Fisch. & Mey. Pods shorter than in 

 the above, and standing out more nearly at right angles, 

 not so stiff and straight, constricted below the narrower 

 style. Caucasus, Afghanistan. B.M. 3757. P.M. G:245. 

 — There are strains of seed saved by Vilmorin-Andrieux 

 & Co., from compact and dwarf plants suitable for edg- 

 ings. (A'. Perofskiamtm nanum, R.B. 32:101. F. nanum 

 conipactum aureum, Gt. 46, p. 194. F. compactum au- 

 reum, Peter Henderson & Co.). 



AA. Plants perennial: height mostly 4-6 in.: rock- 

 garden plants. 



rup6stre, DC. (F. pulchillum, J. Gay). Stem rather 

 woody at base: Ivs. somewhat dentate; stem-lvs. oblong, 

 the hairs short, dense, 2-3-parted. Asia Minor. R.H. 



