324 
TROPICAL NATURE 
IV 
allied species on Chimborazo ranges from fourteen thousand 
feet to the limits of perpetual snow at sixteen thousand feet 
elevation. It frequents a beautiful yellow -flowered alpine 
shrub belonging to the Asteraceae. On the extinct volcano of 
Chiriqui in Veragua a minute humming-bird, called the little 
Flame -bearer, has been only found inside the crater. Its 
scaled gorget is of such a flaming crimson that, as Mr. Gould 
remarks, it seems to have caught the last spark from the 
volcano before it was extinguished. 
Not only are humming-birds found over the whole extent 
of America, from Sitka to Tierra-del-Fuego, and from the 
level of the sea to the snow-line on the Andes, but they in- 
habit many of the islands at a great distance from the main- 
land. The West Indian islands possess fifteen distinct species 
belonging to eight different genera, and these are so unlike 
any found on the continent that five of these genera are 
peculiar to the Antilles. Even the Bahamas, so close to 
Florida, possess two peculiar species. The small group of 
islands called Tres Marias, about sixty miles from the west 
coast of Mexico, has a peculiar species. More remarkable are 
the two humming-birds of Juan Fernandez, situated in the 
Pacific Ocean, four hundred miles west of Valparaiso in Chili, 
one of these being peculiar; while another species inhabits 
the little island Mas-afuera, ninety miles farther west. The 
Galapagos, though very little farther from the mainland and 
much more extensive, have no humming-birds ; neither have 
the Falkland islands, and the reason seems to be that both 
these groups are deficient in forest, and in fact have hardly 
any trees or large shrubs, while there is a great paucity of 
flowers and of insect life. 
Eumming-Urds of Juan Fernandez as illustrating Variation and 
Natural Selection 
The three species which inhabit Juan Fernandez and Mas- 
afuera present certain peculiarities of great interest. They 
form a distinct genus, Eustephanus, one species of which in- 
habits Chili as well as the island of Juan Fernandez. This, 
which may be termed the Chilian species, is greenish in both 
sexes, whereas in the two species peculiar to the islands the 
males are red or reddish-brown, and the females green. The 
