16 
POPULAR HISTORY OF BIRDS. 
turn round and take a run at the birds^ who would quietly 
hop or fly away for a short distance^ but immediately re- 
turn to their avocations in following the pigs. Mr. Wallace 
describes them as entirely guided by sight, and not by smell, 
in seeking out their food, and gives some striking instances 
in proofs. 
The Falconid^, or Falcon family, form the second and 
by far the larger division of the diurnal birds of prey. The 
head and neck are closely covered with feathers, and the eye- 
brows in nearly all the species project over the eye, a cha- 
racter which strikingly alters the physiognomy of the family. 
Although they can live on carrion, yet most of the group 
prefer living prey, which they capture and kill. The fe- 
males are generally much larger than the males. Some of 
the birds belonging to the division Falconincs are capable 
of being trained to pursue game, and to return to their 
keeper when called : in these species the beak has a sharp 
tooth on each side near the hook, and the second quill of 
the wing is the longest. The birds with these characters, 
from their being used in falconry, have been named Noble, 
while all the other falconidous birds of prey, including 
eagles, have been named Ignoble. 
* 'Travels on tlie Amazon and Rio Kegro/ p. 182. 
