ClipArt ETC
"a, b, c, d, inferior laryngeal or syringeal muscles, not well made out in this figure; But typical oscine arrangement (acromyodian) is perceived, inasmuch as anterior (a) and posterior (d) intrinsic muscular masses go to ends of the first tracheal half-ring, at b and c; the extrinsic slip e passing to sternum." Elliot Coues, 1884

The Laryngeal Muscles of a Rook

"a, b, c, d, inferior laryngeal or syringeal muscles, not well made out in this figure; But typical…