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Very similar to hederifolium, especially the flowers. The leaves are less pointed, though, and more rounded. hederifolium is much more uncommon than purpurascens, in Switzerland, only found in the West.
My Flickr photos...
Corolla lobes auriculate at base; flowers appearing before leaves, August - November .... C. hederifolium
Corolla lobes not auriculate at base; flowers appearing when leaves are developed, June - October .... C. purpurascens
Lat/Lng: 46.69, 9.67