This section is from the book "Commercial Gardening Vol2", by John Weathers (the Editor). Also available from Amazon: Commercial Gardening, A Practical & Scientific Treatise For Market Gardeners.
A genus of pretty little rock plants with trailing stems, deeply toothed pinnate leaves, and small flowers. They are quite hardy in most places, and are increased by seeds, division, and cuttings. The best-known kinds are: adscendens, with silvery leaves; Buchanani, with heads of reddish flowers; glauca, with blue-green foliage; inermis, with bronzy stems and light-green leaves; microphylla, one of the most popular for covering rockwork, etc.