British birds

by W. H. Hudson; Frank E. Beddard

Voice Organ.

Fig. 15.—Syrinx of Raven (Posterior Surface).

g, tympaniform membrane.

Fig. 16.—Syrinx of Raven (Lateral View)

a, b, c, e, f, intrinsic muscles; d, sterno-tracheal muscle.

Fig. 17.—Syrinx of Raven cut open Longitudinally.

i, pessulus; h, vibrating membrane; g, membrana tympaniformis.