Stigma load from single butterfly visits on emasculated flowers

_Rhododendron calendulaceum_ twigs bearing budding inflorescences were cut in the field and kept in water in the lab. Flowers were emasculated upon anthesis, and emasculated inflorescences were attached to the end of a pole and presented to foraging _Papilio glaucus_ butterflies near flowering _R. calendulaceum_ plants in the field. Stigmas of emasculated flowers were removed and attached to a microscope slide in the field following a visit, and scored for the presence/absence (=Y/N) of pollen grains and butterfly wing scales upon inspection under the microscope.