328 



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 



Fig. 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 



