Violet; Pansy (Viola), fam. Violaceae.
There are several species in the forest, difficult to distinguish. Yellow Morning Violet (Viola matutina) is most common. In the city, some violet species are grown, too, mostly Heart's ease Pansy (Viola tricolor). Ripe fruits of Heath Dog-Violet (Viola canina) look rather unusually (three last photos): threelobe capsules with small pea-like seeds.
Violet has diuretic, blood-cleaning, vasoconstrictive, expectorant action.
It should be noted that the African (Usambara) Violet (Saintpaulia), one of the most common room flowers, has no relation to true violets. Only the size, sometimes the flower color, and the shape of the leaves may appear similar. Moreover, "Violet root" is actually Orris (Iris) root, which smell is occasionally similar to the flowers of some violet species.