SMELL. 69 



44 These birds, unless when rising- from the earth, sel- 

 dom flap their wings, but sweep along in ogees, and 

 dipping and rising lines, and move with great rapidity. 

 They are often seen in companies, soaring at an 

 immense height, particularly previous to a thunder 

 storm. Their wings are not spread horizontally, but 

 form a slight angle with the body upwards, the tips 

 having an upward curve. Their sense of smelling is 

 astonishingly exquisite, and they never fail to discover 

 carrion, even when at the distance from it of several 

 miles *." Their soaring in the air, whether during a 

 thunderstorm or at any other time, must evidently be 

 not for the purpose of smelling out, but for discovering 

 by the eye some piece of carrion. The Abbe Clavi- 

 gero's account of the black vulture (Catharte urubu, 

 VIEILLOT) is precisely similar. " They fly so high," 

 he says, " that although they are pretty large, they 

 are lost to the sight ; and, especially before a hail- 

 storm, they will be seen wheeling in vast numbers 

 under the loftiest clouds, till they entirely disappear. 

 They feed upon carrion, which they discover by the 

 acuteness of their sight and smell, from the greatest 

 height, and descend upon it with a majestic flight in 

 a great spiral course t." 



When the turkey-vultures roost, they usually sit 

 in companies on the branches of a large tree, and 

 *' they may be seen," says Wilson, " on a summer's 

 morning, spreading out their wings to the rising sun 

 and remaining in that posture for a considerable time. 

 Pennant conjectures that this is to purify their bodies, 

 which are most offensively fetid. But is it reasonable 

 to suppose that that effluvia can be offensive to them, 

 which arises from food perfectly adapted to their 

 nature and which is constantly the object of their 

 desires f?" This is corroborated by the remark of 



* Amer. Orinth. ix. 98, 1st edit. t Hist. Mexico, 



I Amer. Ornith. ix. 97. 



H 



