Pedicularis sylvatica Lousewort CC DD N
The English name of this plant doesn't refer to a herbal cure for lice but the belief was that the meadows in which it grows, cause the cattle to be infested with lice and liver flukes.
Pedicularis is the Latin for louse but sylvatica implies that it is a plant of the woods, forests and hedgerows. I tend to find it in wet meadows in the open rather than shady places.
Pedicularis sylvatica is common in most of the British Isels but is scarcer in the drier eastern parts of England. It is common in Wales, Ireland and Scotland.