This section is from the book "Commercial Gardening Vol4", by John Weathers (the Editor). Also available from Amazon: Commercial Gardening, A Practical & Scientific Treatise For Market Gardeners.
Darwin's Barberry (B. Dartvini), from Patagonia, is another splendid evergreen with arching sprays of small spiny leaves, and orange flowers; and with it may be classed stenophylla (a hybrid between Darwini and empetrifolia) an excellent plant for covert work, etc. B. japonica, B. nepalensis, B. Thunbergi, and B. Wallichiana, are other good kinds, but there are several others not so well known. The common Barberry of our copses and hedges (B. vulgaris) is a deciduous species with about fifty different varieties, one of which (atropurpurea) has rich purple-red leaves. When in fruit in autumn all varieties of B. vulgaris are handsome, especially one called asperma, which has drooping clusters of scarlet oblong berries. Special varieties are usually raised from layers. B. aristata (fig. 415), from North India, resembles the common species, but has large blue-green berries.