SEMPERVIVUM. 



break into sprays carrying only a few rather large waxy flowers of 

 soft clear pink in early summer, with a stripe of deeper rose to each 

 petal. It should be established in cool, damp, and rocky places, there 

 to be let seed itself about at will. 



S. virens is only a Southern form of S. album. 



S. Wallichianum from the Himalaya blooms from June to August, 

 grows half a yard high, and has yellow flowers. It is not likely to be 

 found a species of value. 



Selaginella. — Of these quaint little creeping Club-mosses several 

 may be grown for their bright-green shining carpets in cool places, 

 where they persist through the winter and turn russet. Pieces 

 should be taken off the mass in autumn to be sure of their safety. 

 Species that may be grown are 8. Douglasii, helvetica, Braunii, selagi- 

 noeides (S. spinosa) — all of them pretty and pleasureful coverers of light 

 sandy vegetable soil in a cool place. 



Selliera. See Goodenia. 



Sempervivum. — The Houseleeks form a vast family, most 

 mmutely differentiated, often confused, and often interbreeding. 

 They are all of the easiest culture and the loveliest effect, at least so 

 far as their carpets and masses of rosettes go, — green, blue, violet, 

 ruby ; or of all shades commingled ; or cobwebbed till they are like 

 Ping-pong balls in cotton wool. Their flowers are not always of equal 

 merit — whirling large catherine-wheels gathered in wide heads on stout 

 stems in summer, but sometimes rather dull and indeterminate in tone. 

 However, there are few things in the rock-garden so valuable even for 

 their flowers, as are the Houseleeks for their massed rosettes alone. 

 Any sunny place and any light and rather rich soil, perfectly drained, 

 and thoroughly sunburned, will bake them as happy as the centuries 

 are long. A terrible notion was started some years ago, and gained 

 an astonishing prevalence which even now still lingers; it used to 

 cause these wretched plants to be inserted on rocks in kneaded pats 

 of manure and clay. No more prejudicial or preposterous treatment 

 could be imagined ; the manure goes sour, and the plants, unable to 

 penetrate the hard unwholesome mass with their roots, do not, indeed, 

 always immediately die (for it takes more than difficulty to kill a 

 Sempervivum), but they sit sullen in a hump, and make little or no 

 increase ; until at last, when you awake to the wisdom of moving 

 them, you are ablo to see the sickness and infertility of their sluggish 

 rootage in that odious medium. Not, indeed, that they are hostile 

 to food, or that a little stimulant does not lnightiTy help them to start 

 on inclement ledges and bare rock-faces, but above all they dislike 

 hard impermeable stuff such as this caked mixture produces. Lot a 



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