Cypripedium reginae has a pink lace. P: Petalum S: Sepalum 50: The sink.
The "lip" or Labellum (lip) is a part of the orchid flower, plants belonging to the family Orchidaceae. It is a modified petal, which is clearly distinguished from other petals and sepals because of its large size and generally irregular shape.
The distal part of the lip when it is divided into two parts by a constriction, is called Epiquilo.
The proximal part of the lip when it is divided into two parts by a constriction, is called Hypoquil. Bibliography
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