Dicentra cucullaria: foliage and flowers

Dicentra cucullaria, known in English as "Dutchman's breeches" and in French as dicentre à capuchon, is a perennial woodland spring ephemeral native to parts of North America. It forms mounds of delicately fringed leaves and very nifty and reconizable flowers shaped like little white pants (hanging waist-down as though from a clothesline).

I had never seen this plant in real life, and was very pleased to discover it in a neighbour's garden.