This section is from the book "British Wild Flowers In The Four Seasons", by Thomas Moore. Also available from Amazon: British Wild Flowers.
* Flowers yellow.
D. aizoides: dwarf, tufted; leaves sessile, linear, ciliated; flowers few, rather large. - Rocks, rare. Fl. March, April.
** Flowers white.
D. muralis: annual; stem weak, ascending, leafy; lower leaves ovate or oblong, toothed; flowers white with minute entire petals. - Rocks and walls, rare. Fl. April, May.
D. verna: annual; stem dwarf, erect, leafless; leaves radical, ovate or oblong; flowers small, white, with deeply cloven petals. - Walls and dry banks. Fl. April, May.
 
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