SEMPERVIVUM. 



Group III. Barbatula. — Leaves fringed and tipped with a tuft of hairs. 

 The rest as before. 



S. Pomdlii is placed by some as a hybrid between 8. arvernense and 

 S. arachnoideum, with rosettes of middling size. 



8. fimbriatum, with loose rosettes of rather soft pointed leaves. 

 Besides the points that separate the two groups, this may easily be 

 known from S. montanum, with which it often grows, by its looser 

 rosettes, and the much broader and less spidery petals of its brighter 

 pink flowers. 



Group IV. Arachnoidea. — Dwarf small rosettes with the leaves all 

 interwebbed with more or less of cottony fleece from tip to tip. 



S. arachnoideum is certainly the most important of the smaller rock- 

 garden species. It is a really lovely little jewel, no less in its masses 

 of neat woolly-white balls than when among them rise up stems of 

 3 or 4 inches in summer, expanding sprays of large and comfortable 

 twelve-rayed stars in the most glowing shade of ruby rose, shining on 

 the hot banks of the Alps like little catherine-wheels of living red light, 

 above the crowded whiteness of the globules below. No heat can ever 

 be too great for this plant — the hotter, the happier. In the mountains 

 it is certainly a species that prefers the non-calcareous formations ; 

 it is very abundant, but also very local, and may be seen in carpets in 

 many a warmer exposure at rather low elevations in the Southern 

 ranges, on walls and banks, for choice, but never in the higher alpine 

 turf in company with the large-rosetted species. In the Southern 

 Alps, as the warmth grows greater, so does the density and whiteness 

 of its cobwebbing, until, in the Maritimes, it turns as snowy as wool, 

 and may be seen on the black and crimson porphyry ledges of the Roja 

 valley in hot places, lying like dropped shreddings of a fleece, unrecognis- 

 able as a plant in its congeries of little snowy globes, until the spray- 

 ing heads of scarlet-rosy whirligigs rise up above in brilliant and flaming 

 contrast. This is the lovely form called S. a. transalpinum. Another 

 variety, often quoted in catalogues, is 8. Laggeri, which, in gardens, 

 seems to be merely a rather larger variety of 8. arachnoideum. In 

 the limestone regions of the Jura this species is replaced by the quite 

 similar but much less cobwebby S. Fauconneti, which establishes a 

 connecting link between these small Houseleeks and S. montanum. 

 Another close cousin is 8. barbatulum from the Eastern Alps ; 8. a. 

 bryoeides is a mere form with specially minute and serried rosettes ; 

 and another very tiny miniature variety is 8. a. Cottettii ; while another 



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