COLOURS OF HUMMING-BIRDS. 127 



united. The extremities of the tubes are, however, flat 

 and fibrous. This tubular and retractile tongue enables 

 the bird to suck up honey from the nectaries of flowers, 

 and also to capture small insects ; but whether the latter 

 pass down the tubes, or are entangled in the fibrous tips 

 and thus draw back into the gullet, is not known. The only 

 other birds with a similar tubular tongue are the sun- 

 birds of the East, which however, as we shall presently 

 explain, have no affinity whatever with the humming- 

 birds. 



Colours and Ornaments. The colours of these small 



birds are exceedingly varied and exquisitely beautiful. 



The basis of the colouring may be said to be green, as in 



parrots ; but whereas in the latter it is a silky green, in 



humming-birds it is always metallic. The majority of 



the species have some green about them, especially on 



the back ; but in a considerable number rich blues, 



purples, and various shades of red are the prevailing 



tints. The greater part of the plumage has more or less 



of a metallic gloss, but there is almost always some part 



which has an intense lustre, as if actually formed of 



scales of burnished metal. A gorget, covering the greater 



part of the neck and breast, most commonly displays this 



vivid colour ; but it also frequently occurs on the head, 



on the back, on the tail-coverts above or below, on the 



upper surface of the tail, on the shoulders or even the 



quills. The hue of every precious stone and the lustre 



of every metal is here represented ; and such terms as 



topaz, amethyst, beryl, emerald, garnet, ruby, sapphire ; 



golden, golden-green, coppery, fiery, glowing, iridescent, 



refulgent, celestial, glittering, shining, are constantly 



used to name or describe the different species. 



