Source : WordNet®

mission bells
     n 1: herb of southwestern United States having dark purple
          bell-shaped flowers mottled with green [syn: {black
          fritillary}, {Fritillaria biflora}]
     2: herb of northwestern America having green-and-purple
        bell-shaped flowers [syn: {rice-grain fritillary}, {Fritillaria
        affinis}, {Fritillaria lanceolata}, {Fritillaria mutica}]