194 



INTEODUCTOEY OHAPTBE. 



is very complicated, and diflfers from the human larynx and trachea. 

 It consists of a kind of osseous chamber ; which, however, is only 

 a swelling in the arterial trachea at the point where it bifurcates 

 and enters the breast to form the bronchial tube. It is this 

 formation, called the lower larynx, which constitutes the organ of 

 song. Five pairs of muscles, attached to the walls of this chamber, 

 stretch or relax the vocal chord, by which means they enlarge 



rig. 70. 



Fig. 71. 



or diminish the cavity of the larynx. Whoever has watched any 

 song-bird singing must have noted the swelling and contracting 

 of its throat as it poured out its melody, modifying, in a thousand 

 ways, the tension of the vocal chords and of the larynx, and 

 producing those marvellous modulations whose perfection must 

 always be a subject of astonishment and admiration. 



The song of birds must be the expression of some sentiment ; 

 they surely sing as much for their own pleasure as to charm those 

 who listen to them. While they fiU the woods with their melo- 

 dious accents they direct their looks on all sides, as if proud of 

 their talents, and desirous of gathering the tribute of admiration 

 to which they feel themselves entitled. Their song varies with 

 the season, but it is in the early spring their efforts are the most 

 successful, and we are most disposed to admire the beauty and 

 harmony of their voices. Can anything be more delicious than 

 the warbling of the Linnet, the piping of the Goldfinch, slowly 

 swelling from their leafy bower, or the melodious cadence of the 

 Nightingale, as it breaks the silence of the woodland during the 

 serene nights of leafy June ? 



Our landscape would be sad and mute indeed without these 



