144 CLASS AVES. 



The sonorous and discordant cries of the peacock, are pro- 

 duced, as in all birds, from the bottom of the trachea. The 

 lower larynx, and the bronchise, are provided with mem- 

 branes, whose vibration adds to the dilatation of the voice. 

 The rings of the trachea are entire, round, and osseous. 

 There is no socle at the aperture of the upper lar3nix, but it 

 is furnished with rugosities. 



The rump is very muscular, and its muscles serve as 

 motores to the long dorsal plumes implanted on their meshes, 

 and whose tension, or dilatation, causes them to be raised, 

 spread out, or lowered, according to the inclination of the 

 bird. 



From the small extent of their wings, it would appear 

 that the flight of the peacocks must be low and heavy ; still 

 they can make tolerably long passages in the atmosphere; 

 and the amplitude of their uropygial feathers, which, when 

 the air is agitated, or the wind contrary, might prove an 

 impediment to their progress, must, in calm weather, facili- 

 tate their course, by lessening the specific weight of their 

 bodies. They are fond, as we have observed, of elevated 

 situations, and will perch upon the highest trees, on the tops 

 of towers, and even on the spires of belfries. 



A sympathy has been observed to exist between peacocks 

 and turkeys, wliich are also among the number of those birds 

 that can form the figure of a wheel with their tails ; and they 

 and the peacocks agree better together than either with the 

 rest of the tenants of the poultry-yard. 



Elian extends the life of the peacock to one hundred years, 

 which opinion Willoughby assents to. It must, however, 

 be ranked among the number of fables with which natural 

 history abounds, and which have drawn upon it, tiiough un- 

 deservedly, the contempt of men of sense. The real duration 

 of the life of these birds is not more than five and twenty 

 years. 



