lyo The Bird 



windpipe, and the effect is heightened by the rings which 

 extend as far as the hmgs, which are half-rings or semi- 

 circles, the inner liah'es being replaced l)y membrane. 

 This organ is peculiarly characteristic of birds, there 

 being not a trace of it in any reptile. 



But though the f^yrinx alone is concerned in the pro- 

 duction of sound, this may be modified, made resonant, 

 or gi\'en a reverberating quality by a special structure 

 or by windings of the trachea before it reaches the syrinx, 

 and which are perfect analogies of human musical instru- 

 ments. Many species of ducks have an enlarged box of 

 bone, a kind of drum, on the lower portion of the trachea, 

 sometimes of one shape, sometimes of another, serving, 

 doubtless, to give power to the bird's voice. Cranes and 

 swans have veritable French horns in their breast-bones. 

 The windi)i])e enters between the arms of the clavicles 

 or wiGh-l)one, and describes an S or even a more intricate 

 figure before passing out and dividing into the two bronchial 

 tubes. When a Trumjjeter Swan stretches out its neck 

 and utters a musical clang, most maligned by comparing 

 it to a wlioo]), we should remember the cause of its mellow- 

 ness. In the majestic AMiooping Crane of our Western 

 States, which in a few years will have vanished from the 

 earth, the windings of the trachea reach their maximum. 

 The entire win(l{)ipe of this bird is four feet in length, and 

 of this, one-half is coiled within the sternum, or breast- 

 bone, giving remarkal)le volume and resonancy to the 

 voice. 



