"This beautiful bird," says M. Montes de Oca, "which is generally known in Mexico by the name of the Royal Blue Myrtle-sucker, arrives in the vicinity of Jalapa, Coantepec, and Orizaba in considerable numbers during the months of October and November, and is mostly found feeding from a plant called marapan between the hours of seven and one o'clock. During this time it is seldom seen to alight, and then only for a very short time, but is constantly on the wing, flitting from flower to flower, describing segments of a circle in its flight, and sometimes almost touching the ground. For the remainder of the day very few are to be seen, and I think it probable that they visit the woods for certain kinds of mosquitoes, with which I have often found their stomachs well filled. The pugnacity of this species is very remarkable; it is very seldom that two males meet without an aërial battle. The contest commences with a sharp, choleric shriek, after which, with dilated throats, the feathers of the whole of their bodies erected on end, and their tails outspread, they begin to fight with their bills and wings; the least powerful soon falls to the ground or flies away. I have never known one of these battles last longer than about ten seconds, and in the specimens I have under my notice in cages, their fighting has mostly ended in the splitting of the tongue of one of the two, which then surely dies, from being unable to feed." * * * * * The TRUE SABRE-WINGS (_Platystylopterus_) are recognisable by their comparatively great size and strength, and the unusual development of the shafts of the exterior quills; the tail is straight at its extremity; the beak short and powerful, and almost straight. THE FAWN-COLOURED SABRE-WING. The FAWN-COLOURED SABRE-WING (_Platystylopterus rufus_) is about five inches and a half long, and seven broad. In this species the mantle and central tail-feathers are of a bronze-like green, the under side brownish yellow, and the exterior tail-feathers brownish yellow with a black spot near the tip. This bird is an inhabitant of Guatemala. We are entirely without particulars as to its life and habits. * * * * * The JEWEL HUMMING BIRDS (_Hypophania_) have a powerful and slightly-curved beak and small foot, in some instances covered with down; the wing, which somewhat resembles that of the _Oreotrochilus_, is sometimes short, sometimes long; in the otherwise short tail two of the feathers are generally much prolonged. THE CRIMSON TOPAZ HUMMING BIRD.