WordNet (r) 3.0 (2006):

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