3 28 



The Bird 



and is often so characteristic that when too far off to dis- 

 tinguish the colour of its plumage, or for its notes to 

 reach our ears, the bird may be recognized by the undu- 

 lations or the directness of its flight. No one who has 

 ever visited the tropics can have failed to admire the 



Fro. 263. Wing of living Herring-gull; long and narrow for slow, 

 continuous flight. 



soaring vultures, spots of black swinging across the 

 heavens or swooping low in grand arcs over the palms. 

 Gulls and their kindred fly steadily with continuous wing- 

 beats, which, however, are much less rapid than in the 

 flight of a duck or a parrot. Many sparrows have an 

 abrupt jerking motion, hitching themselves over trees 



