SMELL. 249 



their opinions doubtful. Wilson, for example, 

 speaking of the turkey -vulture (Cathartes aura, IL- 

 LIGER), says, " These birds, unless when rising from 

 the earth, seldom 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 

 upward, 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 thunder-storm 

 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 Clavigero's 

 account of the black vulture (Catharte urubu, VIEIL- 

 LOT) 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 hailstorm, 

 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 great- 

 est height, and descend upon it with a majestic flight 

 in a great spiral course."! 



The raven is another of those birds which have 

 been celebrated for discovering distant objects by 

 the smell, which Bingley thinks " must be very 

 acute ; for in the coldest winter days, at Hudson's 

 Bay, when every kind of effluvia is almost instanta- 

 neously destroyed by the frost, buffaloes and other 

 beasts have been killed where not one of these birds 

 was to be seen, but in a few hours scores of them 

 have been found collected about the spot, to pick up 

 the blood and offal. "J Mr. Knapp is also disposed 



* Amer. Ornith., ix., 98, first edit. f Hist. Mexico. 

 Animal Biography, ii., 242. 



