White Common Foxglove (Digitalis purpurea forma albiflora) flowers, photographed in ultraviolet light.
In ultraviolet the flowers are much darker than in visible light. They lose the darker spots that run down the centre of the lower part of the flower. The interior of the flowers is darker still, but has light strips along either side.
The pollen grains are also much darker in ultraviolet than they are in viisble.
2 images manually combined in Photoshop for exposure.