124 CRASSULACE^. 



brilliant colours or showy qualities of any kind ; their pecu- 

 liar recommendations are rather that they abound in soft tints 

 of flower and foliage, and great variety of form and aspect — 

 they are, in fact, generally humble quiet objects, but attractive 

 and pleasing in a high degree. For the most part they are 

 mountain rock-plants, generally affecting dry habitats where 

 little else will grow but themselves; they are therefore naturally 

 well adapted for ornamenting dry rockwork, for planting in 

 thin gravelly soil, on dry exposed banks, and for draping stumps 

 and stones and old walls or ruins with a varied mantle of 

 interesting vegetation. jSIany of them are excellent border- 

 plants; and, as already alluded to above, some are likely to 

 become popular for many uses in the flower-gardens in bed- 

 ing-out. They are plants of the easiest culture, flourishing 

 abundantly in almost any soil but those that are excessively 

 wet ; but special requirements of species for peculiar purposes 

 will be noticed afterwards in the proper place. All may be 

 propagated by division — that method is unmistakably suggested 

 to even the casual observer by the Sempervivwns generally, 

 which divide themselves, more or less freely, annually; but in 

 nearly every case propagation in this tribe is the most simple 

 matter, whether by division or cuttings. 



Cotyledon umbilicus, syn. Umbilicus pendulinus ( Wall 

 Navelwort). — The genus Cotyledon is a small one, comprising 

 plants of no striking ornamental qualities; but they are useful 

 for planting on old walls with a view to covering them, and are 

 easily established in such positions if inserted in crevices where 

 a little soil or decayed lime or stone exists — anything, in short, 

 that will serve to retain them in their place, along with a little 

 moisture, which is all they appear to want in the shape of 

 nutriment. The species selected grows about 6 or 9 inches 

 high. The leaves are thick, fleshy, and round, with a few re- 

 mote teeth, and attached by their centres to the longish stalks. 

 The flowers are greenish yellow in long racemes, and are pro- 

 duced throughout the summer. Native of Britain and Ireland, 

 and many parts of western Europe. 



Sedum. — This is the most numerous genus in the hardy sec- 

 tion of the tribe. There is a large number of the species in 

 cultivation, but they are chiefly confined to botanic gardens, 

 and only a few of the more common are to be found generally 

 in private ones throughout the country. Some are pretty 

 border-plants, others are suitable for rock-gardens, and gene- 

 rally for furnishing dry gravelly places with vegetation, and 

 draping stumps, old walls, and ruins. Hardy species only are 



