412 ANSERES. PELECANID^E. 



time of the day, in taking a lengthened flight, 

 whether shifting their locality, or slowly sweeping 

 over the sea, they usually take a lineal order. 



In flying thus in lines, I have been struck with 

 the unity which they manifest in their motions: 

 the flight is performed by alternate intervals of 

 heavy flappings, and sailing on outstretched mo- 

 tionless wing ; and the resumption or suspension 

 of the one or the other state, is regulated by 

 the leading bird of the line. For example ; the 

 first begins to flap; in an instant the second be- 

 gins, then the third, then the fourth, and so on, 

 with perfect regularity of succession; and neither 

 ceases till the first does, and then only each in 

 his own turn. That this does not depend on the 

 period of each motion being constant, is shown 

 by the fact, that the duration of either state is 

 very varying and arbitrary. If a bird be follow- 

 ing the same course, near at hand, but not within 

 the line, he does not regard the succession at 

 all, but governs his own motion. 



The Pelican on alighting on the water to swim, 

 brings his feet, which before had been stretched 

 out behind, into a standing position, and, as it 

 were, slides along the surface, for several yards 

 before he swims. 



Voracious and formidable as is the Pelican to 

 the smaller of the finny races, he is not without 

 his enemies among them. I once observed a large 

 Shark gliding along at the surface of the water 

 near a flock of swimming Pelicans, wilily endea- 

 vouring to -approach some unwary one within seizing 



