A deciduous shrub 3 or 4 ft high, of straggling habit, with crooked, much-branched stems. Leaves of two kinds; the first kind 1⁄2 to 1 in. long, 1⁄8 to 1⁄4 in. wide, narrowly obovate, rounded or spine-tipped at the apex, margins without teeth; second kind about the same in length but much wider in proportion, and with three or five large spiny teeth, altogether very much like a tiny holly leaf in form. The leaf-clusters spring from the axils of triple spines, each prong of which is 1⁄2 to 3⁄4 in. long, and as they are often less than 1⁄2 in. apart on the branchlet, the shrub is formidably armed. Flowers solitary, on a stalk 1⁄3 in. long; orange-yellow, with sepals and petals so incurved as to make each flower a little ball. Berries about the size of peas, black, covered with blue bloom, but not often seen in this country.
Discovered originally on the Straits of Magellan by Commerson, but said also to occur wild in other parts of Chile and Argentina. It is a curious and very rare barberry, flowering at Kew in April. It produces sucker growths from the base, by which means it can be propagated. B. ilicifolia Forst., another species with holly-like leaves, bears some resemblance to this, but has short, many-flowered racemes.