Pessulus

The pessulus is a delicate bar of cartilage connecting the dorsal and ventral extremities of the first pair of bronchial cartilages in the syrinx of birds. In some birds such as Anas platyrhynchos the pessulus may be ossified.¹

References

Yilmaz, Bestami; Yilmaz, Rahşan; Arican, Ilker; Yildiz, Hüseyin (2012). "Anatomical Structure of the Syrinx in the Mallard (Anas platyrhynchos)". Harran Üniversitesi Veteriner Fakültesi Dergisi. Retrieved 27 December 2021.

[1] Yilmaz, Bestami; Yilmaz, Rahşan; Arican, Ilker; Yildiz, Hüseyin (2012). "Anatomical Structure of the Syrinx in the Mallard (Anas platyrhynchos)". Harran Üniversitesi Veteriner Fakültesi Dergisi. Retrieved 27 December 2021.

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