A genus of evergreen shrubs and small trees, natives of Australia, found mostly on the eastern side of the sub-continent and in Tasmania. The callistemons belong to the myrtle family, where they are associated with Eucalyptus, Leptospermum, Metrosideros, etc. in the subfamily Leptospermoideae, characterised by a dry, capsular fruit (not fleshy as in the ‘true’ myrtles and their allies). The genus is unmistakable and unlikely to be confused with any other except Melaleuca; but many of the species are poorly defined and in some instances grade into others by intermediates. All are alike in having entire, narrow leaves (round in cross-section in some species), hard in texture and with a prominent midrib. The flowers are in spikes; both sepals and petals are present, but are obscured by the long and very numerous red, yellowish, or greenish stamens, which give to the inflorescence the appearance of a bottle-brush; they are inserted on an ovoid or urn-shaped receptacle. The fruit is a woody capsule, fixed limpet-like to the branch and persisting for many years. A peculiarity of Callistemon (and of Melaleuca) is that the growing-point does not abort after flower production but grows on beyond the inflorescence to produce further stem, leaf, and, in due season, flower. The beautiful genus Melaleuca is too tender for inclusion in this work; it is distinguished from Callistemon by the arrangement of the stamens in several distinct clusters in each flower.