This section is from the book "Handbook Of Hardy Trees, Shrubs, And Herbaceous Plants", by W. Botting Hemsley. Also available from Amazon: Handbook of hardy trees, shrubs, and herbaceous plants.
A large order of shrubs and trees of extremely diverse and curious habit and foliage. Flowers often very brilliant, axillary or racemose, or in dense terminal spikes. Perianth inferior, 4-lobed or -toothed; lobes valvate in bud. Stamens 4, opposite the perianth-lobes. Fruit usually dry and woody, dehiscent or indehiscent, 1-celled, 1- or more seeded. Nearly all the members of this order occur in Australia and South Africa, a few only extending to South America, and northward in the Old World to Abyssinia, India, and Japan. None of the species are quite hardy with us, though some may withstand the ordinary winters of the south-western counties of England. Embothrium coccineum, a native of South America, is one of the hardiest. It is a shrub with simple entire oblong leaves and long pendent orange-scarlet flowers. The perianth is tubular with a sub-globose 4-cleft limb bearing the sessile anthers on the concave lobes. Grevillea robusta, Stenocarpus Cunninghamii, Persoonia Toru, Knightia excelsa, Hakea spp. and Rhopala spp., etc., are handsome shrubs for Summer decoration