A genus of shrubs in which some thirty-eight species are now recognised, of which fourteen were published by Simpson in 1945. All but one (found on Lord Howe Island) are natives of New Zealand. One of the most distinctive features of the genus is the very frequently flattened branches; another is the nearly always leafless condition of the shrubs at maturity; still another is the curious way in which the central part of the pod carrying the seeds falls out when quite ripe, leaving a sort of ring or empty framework. The carmichaelias make no great display of colour but they are pretty and very profuse in flower, and usually charmingly fragrant. The part played in the economy of most plants by leaves is, in this genus, largely performed by the green, flattened stems – not an uncommon occurrence in the broom family. C. petriei and C. enysii are apparently quite hardy; the other species described, with the exception of C. grandiflora, may need a sheltered spot close to a wall facing south or south-west.