284- On the Singing of Birds. 



of the organs of song. But I hope to make these observations 

 more clear, by noticing, that, in the vulture, and other birds 

 of that kind, the muscles of voice are entirely wanting ; while 

 the gallinaceous tribes, as well as the waders and swimmers 

 generally, have but one pair of muscles. The Psittacidae 

 [parrot family] possess three pairs of these muscles of voice : 

 but no birds, I believe, are found to possess four pairs of 

 muscles ; hence, the more we look into the construction of 

 the organs of song in birds, we shall find the more reason to 

 be convinced of their adaptation for the highly interesting and 

 agreeable employment of their vocal powers ; and the more, 

 also, shall we see of the power and wisdom of Him who created 

 them. 



The trachea in song birds (Jig. 38.) is always short and 

 straight ; and, according to the slenderness of the cartilaginous 



SB 



O I )) 1 



The trachea, or windpipe, of the song bird : — a, the superior larynx ; b, the tracheal tube ; c, the 

 inferior larynx ; d, the bronchus, which passes to the lungs ; e e,.the os hyoides, or bones of 

 the tongue; /, the tongue. 



rings, and the spaces between them, so will be the variations 

 of the notes, and the almost endless variety of modulations 

 and inflections, arising from the rapid motion of the laryngeal 

 tube, producing those wonderful effects (to my ears, at least) 

 of piano and forte, or soft and loud ; sounds not only vying 

 with the proudest efforts of art on the violin, flute, clarionet, 

 or even the mellow- toned harp, but still keeping up a strain 

 that never wearies by repetition, but increases our delight by 

 every new variation. 



" Well do I love those various harmonies, 

 That ring so gaily in spring's budding woods, 

 And in the thickets, and green and quiet haunts, 

 And lonely copses." 



" Their tones 



Are sweeter than the music of the lute, 



Or the harp's melody, or the notes that gush 



So thrillingly from beauty's ruby lip."* 



If we notice the tracheal tube of wading and swimming 

 birds {fig. 39., which is a rude sketch of the trachea of the 



* J. M'Lellan, jun., an American poet. 



