Showy Lady Slipper (Cypripedium reginae) has a pink labellum.

P: Petalum
S: Sepalum
L: Labellum

The labellum (or Lip) is part of an Orchid, Canna or other less known flower that serves to attract insects that pollinate the flower, and acts as a landing platform for those insects. Canna (or Canna lily, although not a true Lily) is a Genus of approximately twenty Species of Flowering plants Insects ( Class Insecta) are a major group of Arthropods and the most diverse group of Animals on the Earth with over a million described Pollination in angiosperms and Gymnosperms is the process that transfers pollen grains, which contain the male Gametes (sperm to where the female

The labellum is a modified petal and can be distinguished from the other petals and from the sepals by its large size and its often irregular shape. A petal (from Ancient Greek petalon "leaf" "thin plate" regarded as a highly modified leaf is one member or part of the corolla A sepal (from Latin separatus "separate" + petalum "petal" is a part of the flower of Angiosperms or flower plants It is not unusual for the other two petals of an orchid flower to look like the sepals, so that the labellum stands out as distinct.

References

• Bailey, L. H. - Canna x orchiodes. Gentes Herb. (Ithaca), 1 (3): 120 (1923).
• Chaté, E. - Le Canna, 1866.
• Khoshoo, T. N. & Guha, I. - Origin and Evolution of Cultivated Cannas. Vikas Publishing House.