2o6 The Naturalist in La Plata. 



is, for purposes of bird-portraiture, as good as a live 

 robin ; the same may be said of even many brilliant- 

 plumaged species less aerial in their habits than 

 humming-birds. In butterflies the whole beauty is 

 seldom seen until the insect is dead, or, at any rate, 

 captive. It was not when Wallace saw the 

 Ornithoptera croesus flying about, but only when 

 he held it in his hands, and opened its glorious 

 wings, that the sight of its beauty overcame him so 

 powerfully. The special kind of beauty which 

 makes the first sight of a humming-bird a revelation 

 depends on the swift singular motions as much as 

 on the intense gem-like and metallic brilliancj of 

 the plumage. 



The minute exquisite form, when the bird hovers 

 on misty wings, probing the flowers with its coral 

 spear, the fan-like tail expanded, and poising 

 motionless, exhibits the feathers shot with many 

 hues ; and the next moment vanishes, or all but 

 vanishes, then reappears at another flower only to 

 vanish again, and so on successively, showing its 

 splendours not continuously, but like the intermitted 

 flashes of the' firefly — this forms a picture of airy 

 grace and loveliness that baffles description. All 

 this glory disappears when the bird is dead, and 

 even when it alights to rest on a bough. Sitting 

 still, it looks like an exceedingly attenuated king- 

 fisher, without the pretty plumage ofcthat bird, but 

 retaining its stiff artificial manner. No artist has 

 been so bold as to attempt to depict the bird as it 

 actually appears, when balanced before a flower the 

 swift motion of the wings obliterates their form, 

 making them beem like a mist encircling the body ; 



