184 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



lateral cytnose branches forming a flattish panicle i to 2 inches across. Buds 

 ovate, blunt. Flowers many, | inch across, exceeding the pedicels. Calyx 

 cup-shaped, lobes green, ovate, blunt, equalling the tube, persistent in fruit. 

 Petals lanceolate to ovate, white, blunt, 2 to 3 times the sepals. Stamens spreading, 

 nearly equalling the petals, filaments white, anthers purple. Scales broadly 

 spathulate, yellow. Carpels white, erect | erect also in fruit, when they are 

 streaked red. 



Flowers July. Hardy. 



Habitat. — Europe, Siberia, W. Asia, N. Africa. 



A very common species in gardens, and quite naturalized on walls 

 and rocks in many parts of our own islands, but seldom if ever 

 indigenous there. 



Very variable in leaf, different forms exhibiting in the garden 

 a continuous series from linear (fig. 102, a, a) tp almost globular 

 (fig. 102, c, c) . Near the former end of the series lies the type, described 

 by Linnaeus as " foUis oblongis," while at the other end are the 

 forms described under the names Aihoutn DC. = hrevifolium Boiss., 

 iurgidum DC, &c. Much variation is also found as regards the shape 

 of the leaf in cross-section, some forms being more or less flattened 

 while others are circular. Some of the long-leaved forms have even 

 a groove down the middle of the upper face of the leaf. But in the 

 garden, at least, there is little use in attaching names to any of these 

 forms, since all are linked together by intermediates. The flowers 

 vary also, as regards both length and breadth of petal (see fig. 102), 

 and as regards colour, most fading with a rosy tinge, but some 

 remaining quite white. 



Var. micranthum Bastard (pro specie). 



Illustrations. — Sowerby. "English Bot.," ed. 3, 4, pi. 529, fig. 2. Cusin 

 and Ansberque, "Herb. Flor. Fran9aise, Crassul.," tab. 21. 



' Elle differt du 5. album parce que les feuilles des jeunes pousses 

 sont dress^es et non 6tal^es ; du S. iurgidum par les feuilles cylin- 

 driques peu ou point renfldes ; de tous deux par ses fleurs de moiti^ 

 plus petites.' — Bastard in lift, ex De Candolle, " Flore Fran^aise," 

 Suppl., p. 523. 



I quote the original description because there has been much 

 looseness concerning this plant, the 5. micranthum of some authors 

 and field botanists being only var. hrevifolium Boissier (" folia caulina 

 abbreviata ovato-oblonga ") with flowers as large as, or only slightly 

 smaller than, those of the type. True 5. micranthum I have seen 

 in cultivation only from specimens collected by several correspondents 

 in the Pyrenees. Brevifolium and turgidum seem unworthy of 

 varietal rank ; in that case the distinguishing character of micranthum 

 remains : flowers half the size of those of the type. The flowers of 

 my plants are f those of the type in diameter, which is rather less 

 than \ in area ; the plants are very small and compact, with leaves 

 and stems shorter than in any of the dozens of album forms which 

 I have grown. The occurrence of true micranthum in the British Isles 



