Syringeal Anatomy in the Common Crow

A careful study of the functional anatomy of its syrinx in the Common Crow (Corvus brackyrkynchos) contradicts the view expressed by Welty (1963) that this species is not capable of vocal versatility, i.e. significant variation in pitch and variety of notes produced. Poor vocalizers such as most nonpasserines may have only two or three pairs of syringeal muscles, but true song birds typically have seven pairs, and as many as nine pairs have been reported in some song birds (Welty, 1963: 118-119). Owen (1866) and Ames (1965) describe the anatomy of syringeal muscles in the suborder Passeres. Shufeldt (1890) discusses the muscles of the air passages in the raven (Corvus corax sinuatus). In a preliminary study of sound production in the Common Crow, Miskimen (1951) reports seven pairs of syringeal muscles. Myers (1917) and Gross (1964) describe the functional anatomy of the chicken (Gallus domesticus) syrinx. Ruppell (1933) investigated the vocal structures of the Herring Gull (Larus argentatus). His apparatus for holding the syrinx made it possible to observe the vibration of the vocal membranes, but his review of the literature and experimental work all emphasized the importance of pressure in the interclavicular air sac during sound production. Miller (1934) was able to produce sound with the syrinx of the Great Horned Owl (Bubo virginianus) and Turkey (Meleagris gallopavo) by blowing