FISSIROSTRES.
The last division of the short-footed perching birds, which we have now arrived
at, comprises many groups, presenting among themselves a great diversity of
structure, but all conspicuous for the weakness of their feet. Tn this respect they
resemble the Tencirostres. There is, however, a remarkable difference in the
organization of the two groups, which is accompanied by habits no less dissimilar.
In the last assemblage of birds, the typical distinction rests upon the nourishment
being taken, or captured, by the tongue ; whereas among the F issirostres
this office is performed only by the bill. The whole of these birds, in short,
however different they may appear to a superficial observer, agree in having a
very wide rictus or gape, always broad at its base;’ their food, also, is no longer
vegetable, but is derived entirely from the insect world, and is caught during flight
in the manner of Swallows,—that family, in short, which stands pre-eminently
typical of the whole. The distinguishing characters of all these groups may be
thus stated:—
Analogies.
Coni rost res.
1. Typical group.
f Bill short, triangular; rictus smooth; feet perfect; 1
\ plumage compact.
Families.
HlRUNDINID®.
2. Sub-typical group.
Dentirostres. ( Bill short, triangular; rictus bristled; feet im- 1
( perfect; plumage lax. CaPRIMULGID®.
SCANSORES.
Tenuirostre8.
Fissirostres.
3. Aberrant group.
1 Bill stronger and longer; feet short, imperfect, 1
I and of different constructions.
T rogon I DTE.
Halcyonid®.
Meropid®.
So little has been published on the natural economy of the Trogons, that
hitherto our systematists have been left completely in the dark as to their probable
station in nature. On this point we hope to communicate some interesting
facts, the result of personal observations on these birds in tropical America, in
another place. For the present, we shall merely premise that, as fissirostral birds,
they seize their food during flight; that, as connected to the crepuscular Goatsuckers,
they feed chiefly during the evening; that, as united to Nyctyornis, Sw.,
and Prionites, 111., the bill is either smooth or serrated; that, as allied to the
scansorial Ramphastidce, the Trogons, like the Toucans, are omnivorous. Finally,
who that has seen the superb Trogon Pavoninus of MM. Spix and Temminck,
with its long, gilded, green feathers, is not immediately reminded of a Peacock?
This analogy, in short, has given rise to its specific name, and has been at once
perceived, without the least suspicion that the Trogons actually represented the
Gallinaceous order.
It now only remains to show in what manner the Curtipedes are united into a
circle, by the union of the Fissirostres and Scans ores. We have already intimated
that the Trogons typify the only fissirostral group which is omnivorous ; so also
are the Toucans and the Motmots (Prionites) : the affinity between the two latter
every writer since the days of Linnaeus has perceived ; but the bill of the Mot-
mots is .compressed, while that of nearly all fissirostral birds, as suited to their
peculiar habit of catching their food in the air, is considerably depressed. To
prove, therefore, the connexion of Prionites with the Fissirostres, it was necessary
that a form should be discovered which resembled Prionites, but had the broad bill
of a fissirostral bird; or, in other words, provided with such a flattened bill as is
seen in Galbula grandis. Now it fortunately happens that, although we have
not yet seen it, Mr. Vigors (who places the Motmots as one of the groups of the
Hornbills) has actually proved the existence of the very bird we have theoretically
described, without having the slightest suspicion of the station it occupies in
the chain of Nature. The very name of Platyrhynchus, which that gentleman has
judiciously bestowed upon this most extraordinary bird, is sufficient to show how
widely it differs from all its congeners in the shape, and consequently the functions of the bill. We would ask, therefore, as Prionites is connected with Ramphastos
on one side, into what genus does it merge upon the other ? Whatever that
genus may be, it must have short, weak feet; the bill may be either serrated or
entire, but it must be decidedly depressed, since that is the form which Nature
plainly shows she is about to assume in her new group. We should also expect
to see, in this succeeding link, a continuation of the same shortness of wing and
length of tail, which is so conspicuous in Prionites. Now the only bird yet
discovered, in the whole circle of Ornithology, which realizes this imaginary
description, is the Galbula grandis of Demerara. Unlike all its congeners, it has
a broad, depressed bill, but with the margins entire; it is equal in size to most of
the Motmots; its feet, like theirs, are weak; it has the same kind of short,
rounded wings and lengthened tail; and is, moreover, clothed in nearly the