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deep violet to pure white or yellow. June-August. Alps 

 and southern Jura in pastures from 1000 to 25oo m. 



Culture : this charming plant may be grown in a soil 

 composed of equal parts of leaf-mould, sand and good 

 loam; a cool position, but on no account complete shade. 



Usages: the flower, gathered at the time of opening 

 and dried in shade is much valued by our Highlanders, 

 who employ an infusion of them against affections of the 

 throat and catarrh. 



V. cenisia (PI. XVI 1) is a species near akin, but with 

 subterranean stems which thrust long, winding stolons 

 among the stones. The leaves are longer, thicker, hardly 

 at all notched; the corolla is a trifle smaller and of bluer- 

 violet shade. July-August. Detritus of calcareous Alps 

 from i5oo to 25oo m. 



Culture difficult: requires a well-drained niche in the 

 rockery and sun. 



P. heteropbylla (PL XVI I) is a plant with slender, erect, 

 branched stems; leaves of different sizes and shapes; 

 flowers of medium size and reddish-violet. June-Septem- 

 ber in the south-east Alps, and has acclimatised itself in 

 Valais, both in the neighbourhood of the botanical garden 

 of Linnaea and on the Rochers de Naye below Rambertia. 



V. biflora (PI. XVII). Slender, short plant, with 

 blunted, reniform leaves, of a clear green, flowers small, 

 bright yellow, streaked with violet, scentless, arranged in 

 pairs on an erect stem, which bears one or more leaves. 

 June-August. Moist, shady and cool spots in the Alps 

 and Jura, particularly at the base of rocks. 



Culture: this delightful, yellow-flowered violet may 

 be grown in a cool, spongy, sandy soil (leaf-mould and 

 sand), on the rockery or at the foot of a north wall, or 

 even in shaded gravel. 



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