INE ROD U Cl LON. XXlll

in the subordination and contrast with which the colours are arranged. These extraordinary developments
are nearly always confined to the male, and are, doubtless, bestcwed upon these little gems as a gorgeous
train is given to the Peacock, beautiful markings to the Polyplectron, &c. I know of no others but the
two species of the genus Cephalepis in which a single feather is made to serve the purpose of ornament.
In all other instances the feathers are disposed in pairs, or in equal number on either side of the head or
body, as the case may be; but in both these species the crest terminates in a single plume, which greatly
adds to the elegance of the slender topping. How splendid are the spangles which deck the neck-plumes
of the Lophornithes ! and how well do the blue ear-tufts of the Petasophore harmonize with the surrounding
green of the neck! ‘The genera Oxypoyon and Ramphomicron may be cited as singular instances
of ornamentation ; for they are both bearded and crested. Independently of these extra-developed portions
of the plumage, certain parts of the body are gorgeously coloured ; and here, again, some curious features
are observable. In very many instances the crowns are truly resplendent, as in [Zeliodoxa; while in

Helianthea the forehead only is decorated, with a star brighter than Venus, the queen of planets.

All the members of the genus Heliangelus are remarkable for their beautiful gorgets, succeeded by a
crescent of white separating it from the green of the under-surface. Some species of the Eviocnemides, beside
their thickly clothed tarsi, have rich and luminous upper tail-coverts; while others, such as the Eviocnemis
Aline, have the under tail-coverts unsurpassingly brilliant and beautiful. The members of the genus Augastes
are conspicuous for the shining, metal-like masks with which their faces are adorned ; while, differing from
all these, the 4gleactines have the lower part of their backs clothed in armour-like feathers, the brillianey
of which must be seen to be understood, but which, strange to say, is only apparent when viewed from
behind ; for if looked at in the direction of the feather, none of these hues are perceptible. Many more
instances besides these might be mentioned; but a reference to the plates on which they are represented,
or, still better, the birds themselves, will give a more correct idea of these remarkable colourings than can

be conveyed by any description.

Before leaving the subject of extra development, I may mention that I often find it carried to a greater
extent in some one species of a genus than in the others. I will give an example of what I here intend, by
reference to what is observable in another family of birds, the Trogonide. Here the extra development of
the upper tail-coverts which occurs in members of the genus Pharomacrus commences in the P. pavoninus,
increases in the P. Antissianus, and extends beyond the tail in P. auriceps ; but no species with upper tail-
coverts of intermediate length between those of the last-mentioned species and the immensely long
plumes of P. paradiseus appears to exist. In like manner, among the Andean Humming-Birds there is a
tendency to a gradual increase in the length of the bill, to the extent of two or two and a half inches ; but
no species has yet been seen in which that organ is intermediate between that length and the extraordinarily
developed bill of Doctmastes, which measures at least five inches. A similar fact is also observable with

respect to the spatules in the Spathure.
Apart from developement, I observe that in the Humming-Birds, as in some other groups to which I have
paid particular attention, the species of one genus are much more numerous than those of others, and that,

whenever this is the case, the genus usually comprises many closely allied species.

Among the most pleasing recollections of our youthful days is that of a birds’ nest. Where is the person