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.
Leaves simple and entire. Flowers yellowish, in compound umbels. Calyx-teeth none. Fruits laterally compressed. About sixty species of this genus are known, chiefly from the north temperate zone, a few reaching South Africa. The etymology of the name is uncertain. Most of the species are herbaceous or annual, but the only one that concerns us is shrubby.
1. B. fruticosum. - A small branching shrub with alternate coriaceous obovate-lanceolate mucronate glabrous leaves glaucous beneath, and terminal compound umbels of yellowish flowers with entire involucral bracts. The only shrubby species of the family in general cultivation, and this is not very hardy, and more curious than beautiful. South Europe.