Bitone
The petals and sepals differ in shade or intensity of the same basic color. The petals are the darker shade (e.g., rose pink), while the sepals are lighter (e.g., pale pink). A Reverse Bitone has sepals which are darker than the petals.
Bicolor
The petals and sepals are of different colors (e.g., red and yellow or purple and gold). The petals are the darker of the two colors.
