AN ENCYCLOPADIA 
OF HORTICULTURE. 435 
Silphium—continued. 
opposite, or whorled, entire, toothed, or lobed. The best- 
known species are described below. Dr. Asa Gray says 
of §. laciniatum: “ On the wide, open prairies the leaves 
are said to present their faces uniformly north and south, 
whence it is called the Compass-plant”; this peculiarity, 
according to other authorities, is more noticeable in 
young specimens. 
culture of these plants, which are best placed at the 
backs of flower-beds. They may be increased by division. 
Fic. 485, INFLORESCENCE AND LEAF OF SILPHIUM LACINIATUM. 
S. laciniatum (torn).* Compass Plant; Pilot Weed; Polar 
Plant. j.-heads few, lin. to 2in. broad, somewhat racemose ; 
involucral scales nenn inted ; achenes broadly winged. July. 
l. pinnatipartite, petioled but dilating and ioscan He at base, the 
lower and radical ones ovate, lft. to 24ft. long ; divisions lanceo- 
late or linear, acute, cut-lobed or pinnatifid, rarely entire. A. 3ft. 
to 6ft. Plant rough-bristly. See Fig. 485. (B. M. 6534. 
S. perfoliatum (perfoliate-leaved). E -heads corymbose ; achenes 
winged and variously notched. July. Z. entire, ovate, 6in. to 
15in. long, coarsely toothed, the upper ones united by their bases, 
and forming a cup-shaped disk, ‘the lower ones abruptly nar- 
rowed into winge tioles, which are connate by their bases. 
Stem 4in. to 8in. high, square. (B. M. 3354.) 
S. terebinthinaceum (terebinthine). Prairie Dock. f.-heads 
small; involueral scales roundish, obtuse, smooth ; achenes nar- 
rowly-winged. July to September. l. ovate and ovate-oblong, 
Any ordinary soil is suitable for the, 
Silphium—continued. 
somewhat cordate, serrate-toothed, rough, especially beneath, 
lft. to 2ft. long, on slender petioles. Stem smooth, 4ft. to 10ft. 
mgd, panicled at the summit, and bearing many heads. (B. M. 
c5.) 
S. trifoliatum (three-leaved). f/l.-heads loosely paniculate ; 
achenes rather broadly winged. August. l., cauline ones lanceo- 
late, pointed, entire or scarcely serrate, rough, short-petioled, 
in whorls of three or four, the uppermost ones opposite, Stem 
smooth, rather slender, 4ft. to 6ft. high, branched above. 
(B. M. 3356.) > 
SILVER BELL TREE. ‘sce Halesia. 
SILVER BERRY. The fruit of Eleagnus argentea. 
SILVER BRACTS. A common name for Cotyledon 
Pachyphytum, 
SILVER BUSH. A common name for Anthyllis 
Barba-Jovis. 
See Juniperus virginiana 
SILVER CEDAR. 
SILVER FIR. The popular name for Abies pectinata. 
glauca. 
SILVER-GRAIN. The glittering plates, in ex- 
ogenous wood, caused by the division of the medullary rays. 
SILVER ROD. A common name for Asphodelus 
ramosus. 
SILVER - TREE. See Leucadendron argen- 
teum. The name is also applied to Elwagnus. 
SILVER WEED. See Argyreia. The name is 
also used for Potentilla Anserina. 
SILVER Y MOTH. See Plusia. 
SILYBUM (an old Greek name, applied by Dios- 
corides to some Thistle-like plants). ORD. Composite. A 
monotypic genus. The species is a glabrous, erect, bi- 
ennial herb, included, in some books, under Carduus. 
“The specific name, Marianum, was given to this plant 
to preserve the legend that the white stain on the leaves 
was caused by the falling of a drop of the Virgin Mary’s 
milk” (Lindley). The plant was formerly cultivated for 
culinary purposes, the root being boiled as a potherb, 
the heads treated like those of Artichokes, and the 
leaves used as a spring salad. It occurs in waste places, 
near gardens, &c., but is not indigenous to Britain. Any 
ordinary soil is suitable for its culture. Propagated by 
seeds. 
sS. um (St. Mary’s).* Blessed, Holy, or Our Lady’s Milk 
Thistle. /l.-heads rose-purple, globose, lin. to 2in. in diameter ; 
involucral bracts coriaceous, closely ay rao with one very 
stout, terminal spine; receptacle fleshy, hairy, not pitted. Jul 
to September. J. large, alternate, sinuately lobed or pinnatifid, 
white-spotted above ; teeth or lobes spiny. k. lft. to 4ft. South 
Europe, &c. (Sy. En. B. 681.) 
(the native name in Guiana of one of the 
species). Syn. Zwingera. ORD. Simarubee. A genus — 
comprising about fourteen species of stove, evergreen or 
deciduous trees or shrubs, natives of South America. 
Flowers small or rather large; calyx small, four or five- 
lobed ; petals four or five, longer than the calyx, spread- 
ing, valvate; disk narrow, erect; stamens eight to ten, 
included; panicles loose-flowered, short or elongated. 
Carpels one to five, drupaceous, the endocarp usually 
hard. Leaves alternate, impari- or abruptly pinnate, 
rarely one to three-foliolate; leaflets entire, coriaceous. 
Three species have been introduced, but S. Cedron is 
probably the only one now known in cultivation in this 
country. This is a small tree, remarkable for the febri- 
fugal properties of its seeds, which have also been, from 
time immemorial, reputed, in its native place, as a 
remedy for snake-bites. It thrives in well-drained, turfy 
loam. Propagated by cuttings of the ripened wood, in- 
serted in sand, under a glass, in heat; or by imported 
seeds. 
S. Cedron. Cedron-tree. f. di d in racemes 3ft. to 4ft. 
long. May. fr. about the size of a swan’s , 0 , four 
of the cells being barren. l. large, pinnate ; leaflets twenty or 
more, narrow-elliptic, beer” ays above, paler beneath. Trunk 
simple, erect, slender. A4. 20ft. New Granada, 1846. 
