494 



EXPLANATION OF PLATES. 



Plate XI. Respiratory and Vocal Organs of the Rook, Corvus 



fruffileffus. 



Fig. 1. Respiratory, Vocal, and Diges- 

 tive Organs of the Rook. 



a, the tongue. 



b, uro-hyal bone. 



c, c, horns of hyoid bone. 



d, d, genio-hyoidei. 



e, e, stylo-hyoidei. 



f, f, cleido-thyroidei. 



g, h, i, oesophagus. 

 .;', proventriculus. 

 A, stomach. 



I, m, n, n, duodenum and rectum. 



0, 0, p, trachea. 



q, inferior larynx, with its muscles. 



r, r, bronchi, 



s, s, contractor muscles. 



t, t, lungs. 



ti,, u, aperture communicating with the 



thoracic cells. 

 V, V, V, three pairs of muscular slips 



analogous to the diaphragm. 



1, 2, 3, 4, 5, 6,7, ribs. 



Fig. 2. Hyoid Bone. 



a, glosso-hyal element. 

 h, basi-hyal. 



c, uro-hyal. 



d, d, apo-hyal. 



e, e, cerato-hyal. 



/,/i terminal cartilages. 



Fig. 3. Aperture of the Trachea or 

 Glottis. 



a, base of tongue. 



b, b, branches of hyoid bone. 



c, rima glottidis. 



d, triangular vacuity. 



e, elastic ligament. 



y,/, oval pad covered by papillae. 



Fig. 4. Bones of the Larynx viewed from 



before, 

 a, thyroid bone, 



Fig. 5. Bones of the Lirynx viewed from 

 behind. 



a, thyroid bone. 



b, b, appendages to the thyroid bone. 



c, cricoid bone. 



d, d, arytenoid bones. 



e, e, anterior margin of thyroid bone 

 with the two arytenoid ligaments. 



Fig. 6. Bones of the Larynx viewed 

 laterally. 



a, thyroid bone. 



b, its appendage. 



c, cricoid. 



d, arytenoid. 



f,f, cartilage appended to the aryte- 

 noid. 

 g, rings of trachea. 



Fig. 7. Bones of the Larynx viewed 

 from behind. 



a, thyroid. 



b, b, its appendages. 



c, cricoid. 



d, d, arytenoid. 



Figs. 8, 9, 10, 11, 12. Muscles of the 

 Larynx. 



1, 1, thyro-hyoidei. 



2, 2, thyro-arytenoidei, or apertores 



glottidis. 



3, 3, arytenoidei-obliqui. 



4, 4, thyro-cricoidei. 



5, 5, thyro-cricoidei postici. 



Fig. 13. Bifurcation of the Trachea, 

 a, a, b, last entire ring. 



Fig. 14. Last eiitire Ring of Trachea, 

 viewed from beneath. 



Fig. 15. Bifurcation of Trachea and 

 Bronchi viewed from beneath. 



a, bone of divarication. 



b, b, last or divided tracheal rings. 



Fig. 16. Inferior Laryngeal Muscles. 



a, anterior internal muscle. 



b, anterior external muscle. 



c, intermediate muscle. 



d, posterior muscle. 



Fig. 17. Trachea of the Nightingale. 



