230 THE STORY OF THE BIRDS 



variety of ways, the spatulate ends sometimes 

 being bent forwards almost to the crown of 

 the head. This Humming-Bird is not a very 

 brightly coloured one, the tail being apparently 

 the principal decoration, and therefore manipu- 

 lated accordingly. Belt observed two males of 

 another Humming-Bird, the Florisuga mellivora, 

 displaying their charms in a sort of friendly 

 rivalry before a single female of the same species. 

 First one would dart upwards, suddenly ex- 

 panding the snow-white tail, which, like an in- 

 verted parachute, covered more space than the 

 rest of the bird, and then gradually descend, 

 turning slowly round, displaying both back and 

 front ; then the other would soar as its com- 

 panion came down, going through precisely the 

 same actions. Some of the Tyrant Birds are 

 also remarkable for aerial display. One of these, 

 Cnipolegus hudsoni, is black with a white bar 

 on the wings. It is in the habit of sitting on 

 a dead twig at the top of a bush, at intervals 

 leaving this perch and beginning literally to 

 waltz round and round in the air so rapidly 

 that the wings, looking like a mixture of black, 

 white and grey mist, make a loud humming 

 sound. Just as suddenly this wild fantastic 

 dance ceases, and the bird resumes its perch to 



