The pessulus is a delicate bar of
cartilage connecting the dorsal and ventral extremities of the first pair of bronchial cartilages in the
syrinx
In classical Greek mythology, Syrinx (Greek Σύριγξ) was a nymph and a follower of Artemis, known for her chastity. Pursued by the amorous god Pan, she ran to a river's edge and asked for assistance from the river nymphs. In answer, s ...
of birds. In some birds such as ''
Anas platyrhynchos
The mallard () or wild duck (''Anas platyrhynchos'') is a dabbling duck that breeds throughout the temperate and subtropical Americas, Eurasia, and North Africa, and has been introduced to New Zealand, Australia, Peru, Brazil, Uruguay, Argen ...
'' the pessulus may be ossified.
References
Bird anatomy
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