212 



GENERAL ORNITHOLOGY. 



Fig. 101 — Respiratory and vocal organs of the Rook, Corvus frugilegus, an Oscine Passerine bird ; nat. size, 

 after Macgillivray. 1. a, tongue; ft, basi-brancliial, commonly called uro-hyal; c, c, horns of hyoid bone; d.<l, 

 genio-hyoid muscles; e, e, stylo-hyoid muscles; /,/, cleido-hyoid muscles; g. h, i, oesophagus; j, proventriculus; 

 or secretory stomach; k, gizzard, or gigerium, the muscular stomach ; ;, m, n, n, intestine, duodenum to rectum ; 





