Water Ermine is a tiger moth,
Spilosoma urticae. Wings white, the fore pair each with a black dot; head and thorax white, body yellow, the tip snowy white, with a row of black spots down the back, and one on each side. Caterpillar black, very hairy. It feeds in marshy places on mint and willow herb, concealing itself on the under side of the leaves. The moth appears in June.
Water ermine