UTILITY OF BIRDS IX NATURE. 



cannot at its best equal the bird. I once saw a bat make 

 seven attempts to catch a moth fluttering along the still sur- 

 face of a moonlit river. A Swallow could have seized it at 

 once with no perceptible effort. Xo creature can equal the 

 soaring of the Eagle or Vulture, or that of the Man-o'-War 

 Bird as it sails on high above the storm ; while the speed 

 that the Hummingbird attains is such that the eye can 

 scarcely follow its most rapid flight. 



Birds are provided with wings to enable them ( 1 ) to pro- 

 cure food, (2) to escape their enemies, (3) to migrate. 



All birds have wings, though a few, like the Apteryx, have 

 them only in a rudimentary form. Others, like the Penguin 

 and the Ostrich, have small wings, but cannot raise them- 

 selves in the air. 



All birds that cannot fly, however, are reminders of a past 

 age, and are not fitted to live on the same earth with man. 

 Such birds are either already extinct or in a fair way to 

 become so, either at the hands of man or at the teeth or 

 claws of the dogs, cats, or other animals that man introduces. 

 Flight alone might save the few that remain. The Great 

 Auk, using its wings only in pursuing its prey under water, 

 disappeared before the onslaught of the white man ; while 

 the Loon, flying both under water and above it, still sur- 

 vives. 



Birds are pursued by many enemies. Water-fowl fly to 

 the water and dive to escape the Hawk or Eagle, and fly to 

 the land to escape the shark, alligator, or pike. Sparrows 

 fly to the thicket to elude the Hawk, and to the trees to 

 avoid the cat. Evidently this great power of flight was given 

 to birds to enable them not onby to concentrate their forces 

 rapidly at a given point, but also to pursue other flying 

 creatures. Birds can pursue bats, flying squirrels, flying 

 fish, and insects through the air. Bats and insects are their 

 only competitors in flight. Comparatively few insects can 

 escape birds by flight, and this they do mainly by quick 

 dodging and turning. The speed at which birds can fly on 

 occasion has seldom been accurately measured. The maxi- 

 mum flight velocity of certain wild-fowl is said to be ninety 

 miles an hour. Passenger Pigeons killed in the neighbor- 



