SAXIFHAGACEJE. 65 



Herbs or undershrubs, with alternate or rarely opposite leaves 

 and flowers variously disposed, white, yellow, rose-colour, or purple. 



The generic name of these plants seems to be in allusion to their supposed medical 

 virtues, and to come from the words saxum, a stone, and frangere, to break. 



Section I.— PORPHYRION. Tausch. 



Stems elongated, perennial, leafy. Leaves small, opposite, per- 

 sistent, thickened towards the apex, where there are 1 to 3 pores 

 at first covered with deciduous calcareous scales, ciliated with the 

 cilise not articulated to the margin of the leaf. Plowering-shoots 

 short, annual. Sepals cohering to the middle, erect, free, or adnate 

 to the ovary, purple, rarely yellow. 



SPECIES I.-SAXXFR AG A OPPOSITIPOLI A. Linn. 

 Plate DXL. 



Stems much branched, prostrate. Leaves crowded, opposite, 

 4-farious, oblong-oblanceolate, thickened and obtuse at the apex. 

 Flowers terminal, solitary, sub-sessile. Calyx free from the ovary ; 

 segments ciliated, with the cilia? not glandular. Petals obovate, 

 rose-lilac fading to purple. Stamens shorter than the corolla. 

 Seeds oblong-triquetrous, rugose. 



On the damp ledges of alpine rocks. Rare in Merioneth, 

 Carnarvon, Yorkshire, and Cumberland. Common in the Scotch 

 Highlands. 



England, Scotland, Ireland. Perennial. Summer. 



Stems much-branched, prostrate, reddish-brown, with the leaves 

 generally crowded, especially towards the apex of the shoots. Leaves 

 about i inch long, recurved towards the apex, somewhat cartilagi- 

 nous, mostly with fascicles of leaves or abbreviated shoots in their 

 axils, ciliated with thick white hairs, which seem to be a production 

 of the substance of the leaf itself, slightly channelled above nearly 

 to the apex, which is marked with usually a single pore. Flowering- 

 shoots i to 1 inch long, with the leaves crowded or distant. Flowers 

 i inch across, bell-shaped, pale reddish-purple, but losing some of 

 the red tinge as they fade. Calyx-segments broadly-ovate, obtuse. 

 Petals oval-obovate, scarcely acute, with a central nerve giving off 

 two opposite branches near the base, and these lateral nerves dividing 

 into 2 a little way above their origin. Capsule £ inch long (exclu- 

 sive of the beaks), ovate-ovoid, terminating in 2 long diverging beaks. 

 Seeds reddish-brown. Plant deep-green, glabrous. 



Purple Mountain Saxifrage. 

 French, Saxifrage a Feuilles oppos'ets. German, GegenblaUriger Steinbrech. 

 VOL. IV. K 



