This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol2", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Fleshy perennial herbs, the thick succulent leaves densely imbricated on the short sterile shoots and scattered on the erect flowering stems, with compound terminal usually dense cymes of showy flowers. Flowers 6-20-parted. Petals distinct, oblong or lanceolate, acute or acuminate. Stamens twice as many as the petals. Styles filiform; ovules ∞. Follicles many-seeded. [Latin, always living.]
About 40 species, natives of the Old World, chiefly distinguished from Sedum by the more numerous parts of the flower, the following typical.
Sempervivum tectorum L. Sp. Pl. 464. 1753.
Flowering stems about 1° high, the barren shoots forming lateral nearly globular tufts. Leaves oval or ovate, the lower 1'-1 1/2' long, very thick, short-pointed, bordered by a line of stiff short hairs; cyme large, dense; flowers sometimes 1' broad, pink, sessile along its spreading or recurved branches; petals lanceolate, acute, 2 to 3 times as long as the obtuse ciliate sepals.
Essex Co., Mass.. escaped from gardens and reported as well established; Somerset Co., N. J. Native of continental Europe. Summer. Healing-blade. Aye-green. Bullock's-eye. Poor Jan's-leaf. Jupiter's-beard. Hen-and-chickens. Old English names, homewort, sengreen and thunder-plant; a fancied protection against lightning, as well as fire.