What is syrinx

Syrinx

Syrinx is a 'vocal organ' which is found only in birds.  It produces sound in birds. It is situated between trachea and bronchi of a bird. Supported by last few(three) tracheal rings and first two brnnchial rings.
    
Syrinx consist of expanded chamber called "Tympanum" which is also supported by last three or four tracheal rings and first two rings of bronchi.

       The voice is produced by the vibration of tympaniform membrane
when the air expelled out from the lungs.

Mucous membrane of each bronchus forms an internal tynpaniform membrane and External tympaniform membrane. These membranes are regulated by "Intrinsic syringial muscles" and apair of "Sterno-tracheal muscles".
  At the junction of two bronchi a bony ridge,the "Persulus" extends dorso-ventrally.

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