100 THE OCEAN. 



habit, to allure the bird to its destruction ; for they 

 fix a fresh herring to a board, and draw it after a 

 sailing boat with some rapidity through the waves ; 

 by which many are killed in the manner just 

 narrated. The apparatus by which this bird is 

 furnished for its aerial powers, as well as for aiding 

 its arrowy descent, is very beautiful and instructive. 

 Professor Owen, by inserting a tube into the wind- 

 pipe, was enabled to inflate the whole body with air, 

 and found that air-cells communicating with each 

 other pervaded every part, separating even the 

 muscles from each other, and isolating the very 

 vessels and nerves, and penetrating the bones of the 

 M'ing. A large air-cell was found to be placed in 

 front of the forked-bone, or clavicles, which was 

 furnished with muscles, whose action was instant- 

 aneously to expel the air, and thus in a moment to 

 deprive the bird of that buoyancy, so necessary for 

 its flight, but equally detrimental to its swoop. 



In some interesting observations, by Colonel Mon- 

 tagu, on the habits of this bird in captivity, the same 

 fact is noticed. When the bird was placed on the 

 water of a pond, nothing could induce him to attempt 

 to dive, and from the manner of his putting the bill, 

 and sometimes the whole head under water, as if 

 searching for fish, it appears that the prey is fre- 

 quently so taken. It is probable more fish are caught 

 in their congregated migrations, when the shoals are 

 near the surface, than by the bird's descent upon 

 the wing ; for the herrings, pilchards, mackerel, and 

 other gregarious fishes, cannot at that time avoid their 

 enemy, who is floating in the midst of profusion. la 



