I opened the stomachs of several specimens, shot in different parts of the continent, and in all, remains of insects were as numerous as in the stomach of a creeper.

When this species migrates in the summer southward, it is replaced by the arrival of another species coming from the north.
This second kind (Trochilus gigas) is a very large bird for the delicate family to which it belongs: when on the wing its appearance is singular.

Like others of the genus, it moves from place to place with a rapidity which 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.