180 CARIPI. Chap. V. 



motions are unlike those of all other birds. They dart 

 to and fro so swiftly that the eye can scarcely follow 

 them, and when they stop before a flower it is only for a 

 few moments. They poise themselves in an unsteady 

 manner, their wings moving with inconceivable rapidity, 

 probe the flower, and then shoot off to another part of 

 the tree. They do not proceed in that methodical 

 manner which bees follow, taking the flowers seriatim, 

 but' skip about from one part of the tree to another in 

 the most capricious way. Sometimes two males close 

 with each other and fight, mounting upwards in the 

 struggle as insects are often seen to do when similarly 

 engaged, and then separating hastily and darting back 

 to their work. Now and then they stop to rest, perch- 

 ing on leafless twigs, when they may be sometimes 

 seen probing, from the place where they sit, the 

 flowers within their reach. The brilliant colours with 

 which they are adorned cannot be seen whilst they 

 are fluttering about, nor can the different species be 

 distinguished unless they have a deal of white hue in 

 their plumage, such as Heliothrix auritus, which is 

 wholly white underneath although of a glittering green 

 colour above, and the white-tailed Florisuga mellivora. 

 There is not a great variety of humming-birds in the 

 Amazons region, the number of species being far smaller 

 in these uniform forest plains than in the diversifled 

 valleys of the Andes, under the same parallels of lati- 

 tude. The family is divisible into two groups con- 

 trasted in form and habits, one containing species which 

 live entirely in the shade of the forest, and the other 

 comprising those which prefer open sunny places. The 



