Fig. 5. The cockatiel syrinx is situated at the distal end of the trachea cranial to the bronchi. (A) Schematic external ventral view of the cockatiel syrinx depicting the syringeal muscles and the inserted angioscope. Note the slightly asymmetric m. sternotrachealis (ST). (B) Schematic left-side view illustrating the extent of the paired protrusions (PP). (C) Schematic horizontal section through the cockatiel syrinx with the approximate position and field of view of the angioscope (yellow light) in Figs 6a–f and 7. SP, m. syringealis profundus; SS, m. syringealis superficialis; BC, bronchial cartilage; T, trachea; TL, m. tracheolateralis; TY, tympanum (consisting of four closely apposed or fused tracheosyringeal cartilages); LTM, lateral tympaniform membrane.
