The story
Alluding to the shape of its seed vessel. Compare mediaeval Latin bursa pastoris, French bourse-à-berger, German Hirtentasche.
Etymology from Wiktionary, CC BY-SA 4.0.
shepherd's purse
Today it means: An edible weed, Capsella bursa-pastoris, family Brassicaceae, native to Europe but now found world-wide. Full definition →