1) Brassicaceae 2) Dilleniid dicot genus 3) Genus capsella 
[bivalve] Capsella is a mollusc genus in the family Donacidae, the bean clams or wedge shells. ...[plant] Some recent authors circumscribe Capsella to contain only three species: Capsella bursa-pastoris, Capsella rubella and Capsella grandiflora. == Species == ...
(Shepherd's Purse) This frost-hardy annual is originally from Europe and has naturalized widely. This plant has a flavor resembling Mustard. The branched stems rise up from a basal rosette of leaves. In early summer, spikes, 12 to 2 feet high and bearing white flowers, rise out of the foliage. The blossoms are followed by purse-shaped fruits.â...
[n] - shepherd`s purse
genus Capsella noun shepherd`s purse