6 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



S. maximum, and S. Anacampseros, and one Rhodiola, the ubiquitous 

 S. roseum — if we except S. quadrifidum, which spreads from Arctic 

 Asia just into Russia. Almost all the perennial species are in culti- 

 vation, though in some cases very rarely ; a few Balkan and Greek 

 plants are yet unknown in gardens. Some of the annual plants are 

 found in gardens, but the pretty blue S. coeruleum is the only one 

 of value. 



In our own islands eight species are undoubtedly native — namely, 

 roseum, Telephium, album, anglicum, acre, reflexum, rupestre, villosum. 

 Several others, such as dasyphyllum and sexangulare, are naturahzed. 

 Most of our native species have been spread by human agency much 

 beyond their original native limits. 



Literature. — Nyman, "Conspectus Florae Europeae," and Sup- 

 plements. 



Africa. 



The Mediterranean Httoral yields a number of the familiar species 

 of southern Europe, and also some endemic plants, such as S. multiceps 

 (well known in cultivation) and the curious S. tuberosum. A few 

 species occur on the mountains of Abyssinia, and one or two others 

 have recently been discovered as far south as the Equator, on Mt. 

 Ruwenzori. R, Hamet reduces * the nine species which have been 

 described from the interior of Africa to five — namely, abyssinicum 

 Hamet, Meyeri- Johannes Engler, ruwenzoriense Baker fil, Epiden- 

 drum Hochstetter, sediforme Hamet. None of these is known in 

 cultivation. 



The Atlantic Islands. 



Madeira yields three species of Sedum — S. farinosum Lowe (possibly 

 an extreme form of the European album) and two yellow-flowered 

 species, fusiforme and nudum, apparently related to those of Central 

 Africa and Central America. The Canaries possess S. lancerottense 

 (closely aUied to the Madeiran nudum) and the Mediterranean annual 

 rubens ; possibly also a third species undescribed (a poor specimen 

 in Herb. Kew.). Of the above, nudum and lancerottense are in culti- 

 vation. 



The Caucasus. 



The Caucasian region is particularly interesting as being the 

 headquarters of two very distinct sections of the genus — the group 

 Involucrata of Marschall von Bieberstein, of which the famiHar 

 spurium is a characteristic example ; and the still more distinct little 

 group of the Sempervivoides. Most of these are confined to the 

 Caucasus, but a few are found in the adjoining regions of Asia Minor or 

 Persia. The Involucrata number half a dozen species, with roundish, 

 flat, mostly opposite leaves and red or white flowers. Of these, 

 spurium is very widespread in cultivation, with crimson, pink, or 



♦ In litt., Herb. Brit. Museum. 



