Dutchman's Trousers????

Scientific Name
: Dicentra Spectabilis

Family
: Fumariaceae

Common names
: Bleeding Heart, Dutchman's Trousers

Flowering Season
: May-August

Colour
: Red, Pink, White


Spotted these little beauties while hanging out the zillionth load of washing. Knew they are known as Bleeding Heart, which I thought appropriate for Easter. On Googling however I discovered they have another name. Any suggestions as to WHY??? gratefully received, but keep it (moderately) clean......