Among other sources from which rubber is commercially obtained may be mentioned the Guayule plant (Parthenium argentatum) of Mexico, and the "Ecanda " plant of Portuguese W.
Parthenium and Maenalus on E.
P. parthenium, pellitory or "feverfew," was formerly used in medicine.
Pyrethrum Parthenium aureum: half-hardy, I ft.; grown for its golden foliage, and much used for bedding.
P. Parthenium eximium, 2 ft., is a handsome double white form of ornamental character for the mixed border; P. uliginosum, 5 to 6 ft., has fine large, white, radiate flowers in October; P. Tchihatchewii, a close-growing, dense evergreen, creeping species, with long-stalked, white flower-heads, is adapted for covering slopes in lieu of turf, and for rockwork.
Sylvestris; Phloxes, like P. subulata, with its varieties setacea, Nelsoni, nivalis; the single-flowered varieties of the Primrose, Primula vulgaris; the Polyanthuses; Pyrethrum Parthenium aureum, called Golden Feather; Sempervivum calcareum; the pinkflowered Silene pendula; self-coloured varieties of the Pansy, V.
Metallica are much employed; Gazanias; Heliotropes; Iresines; Lantanas; Lobelias; Mesembryanthemum cordifolium variegatum; Pelargoniums, of which the various classes of zonal or bedding varieties are unapproachable for effect and general utility; Petunias; Phloxes; Polemonium coeruleum variegatum; Pyrethrum Parthenium aureum, the well-known Golden Feather, especially useful as an edging to define the outline of beds upon grass; Tropaeolums, especially some of the varieties of T.
Olonos) to 7400, of Cyllene (Ziria) to 7900, in the southern corner buttresses of Parthenium and Lycaeum to more than 5000 ft., this inland plateau is again divided by numerous subsidiary ranges.
The Alternantheras, Amaranthuses, Iresines and Coleus Verschaffelti furnish high and warm colours; while Pyrethrum Parthenium aureum yields greenish-yellow; Thymus citriodorus aureus, yellowish; Mesembryanthemum cordifolium variegatum, creamy yellow; Centaureas and others, white; Lobelia Erinus, blue; and the succulent Echeverias and Sempervivums, glaucous rosettes, which last add much to the general effect.