272 CENTRAL CHILE. (CHAP, Xtr 
may be compared to that of Syrphus amongst flies, and Sphinx 
among moths; but whilst hovering over a flower, it flaps its 
wings with a very slow and powerful movement, totally different 
from that vibratory one common to most of the species, which 
produces the humming noise. I never saw any other bird, where 
the force of its wings appeared (as in a butterfly) so powerful in 
proportion to the weight of its body. When hovering by a 
flower, its tail is constantly expanded and shut like a fan, 
the body being kept in a nearly vertical position. This action 
appears to steady and support the bird, between the slow 
movements of its wings. Although fying from flower to flower 
in search of food, its stomach generally contained abundant re- 
mains of insects, which J suspect are much more the object of its 
search than honey. The note of this species, like that of nearly 
the whole family, is extremely shrill, 
