ON ROCK PLANTS. 299 



pyramidal flower stem, ift. to' 2ft. high, and covered from May 

 to July with large white flowers. .S. longifolia has large rosettes 

 of silvery leaves, 6in. long, and bears white flowers, dotted with 

 red, on much-branched flower-stems ift. high. S. pyramidalis 

 is merely a robust variety of S. Cotyledon. 



(2) The Mossy Section contains the dense, moss- or 

 cushion-like Saxifrages ; of these S. hypnoides and »S. muscoides 

 are examples. The former bears small white flowers, on stems 6in. 

 to i2in. long, from May to July; the latter, known also as 

 S. moschata, bears racemes of pale yellow or purple flowers during 

 May and June. 



(3) The Oppositifolia Section comprises those with small 

 opposite leaves. The typical plant, S. oppositifolia, has leafy, 

 creeping stems, 6in. to 8in. long, and produces solitary bright 

 purple flowers during April and May. Its variety pyrenaica 

 also has purple flowers, and is an excellent rock-garden plant. 

 Several other varieties are also grown. 



(4) The Round-leaved Section includes such kinds as 

 S. sarmenlosa, S. umbrosa, and .S. rotundifolia. The first, how- 

 ever, is only half-hardy. S. umbrosa (London Pride) is a well- 

 known plant, sending up a leafless flower-stalk 6in. to i2in. high; 

 the flowers, which are borne in a panicled cyme, are white, but 

 often spotted with red. »S. rotundifolia has white flowers marked 

 with scarlet dots. 



(5) The Large-leaved Section comprises the species with large 

 leaves, commonly known in gardens as Megaseas. Of these the 

 following are best known : 6 1 . cordifolia (Megasea cordifolia), with 

 large cordate leaves and clusters of bright rose-coloured flowers; 

 it grows ift. high, and flowers from March to May. S. crassifolia 

 has large oval leaves, which are fleshy and shining; in April 

 and May it bears clusters of reddish flowers on stalks ift. in 

 height. S. (Megasea) purpurascens has large, smooth, purple 

 leaves; the flower-stems are i2in. high, and are surmounted with 

 clusters of bright purple flowers in June. .S. Stracheyi has large 

 shining green leaves, and lovely pink flowers upwards of iin. 

 across, produced in March and April on stems 9m. high. 



Sedums (Stonecrops) are essentially rock-garden plants, and 

 also succeed well on old walls, ruins, &c. Some, such as 

 5. glaucum and S. lydium, are also useful for carpet-bedding. 

 They thrive in almost any position, and are easily increased 

 either by seeds, by cuttings, or by division. £. acre, although a 

 British plant, is much grown ; it sends out numerous barren, 

 creeping shoots, from which rise dwarf erect branches bearing 

 yellow flowers ; its variety aureum has the tips of the leaves of a 

 bright golden-yellow during the spring. S. album grows 6in. high, 

 and produces its cymes of white flowers on pinkish stems 

 during June and July. S. glaucum grows from 3m. to 4m. high, 

 and bears cymes of white flowers. S. kamtschaticum has prostrate 



