The first group we are to notice in the sub-family of the
MERULIN/E,
or True Thrushes, is composed of such as frequent rocks, or stony ground; having
rounded wings, lengthened tarsi, and feet more adapted for walking than for
perching : such birds, in short, as appear to enter in the genus Petrodncla, Vig.
Between these and the Song Thrushes the affinity is too marked, and too close, to
require pointing out. The genus Merula comprehends the Blackbird, Throstle,
and the whole of the European Thrushes; and numerous species of this typical
group are found in every temperate and tropical region, both of the Old and New
World. The genus Orpheus, Sw., has a more limited range ; no examples
occur in Europe; and such as exhibit the typical structure are all from America.
If we regard the uncommon powers of song possessed by the Mocking-Birds, as
sufficient to confer upon them the typical distinctions of this family, the genus
Orpheus will hold that station. But if we consider that a more perfect organization
for all other purposes, should guide us in this decision, then the title must be
conferred upon Merula ; in either case the peculiarities of the two groups point
them out as the leading types of the whole family. We have not yet satisfied
ourselves on the precise nature of the two remaining types of this division, and
shall therefore forbear hazarding any opinion. That the Merulinm unite with
the Long-legged Thrushes, we can, however, entertain no doubt. The Orpheus
rufus of North America exhibits, like these latter birds, a perfectly entire bill,
strong feet, short wings, and lengthened tail; and when such an ornithologist as
M. Temminck describes our Orpheus longirostris (which, in fact, is the Mocking-
Bird of Mexico) as a decided Pomatorhinus, the absence of the intermediate forms
will not, in our opinion, materially affect the accuracy of our arrangement.
The appearances of Nature, nevertheless, are so deceptive, that the oldest and
most experienced of her students are perpetually mistaking her relations ; and if
we were to proceed only by the synthetic method, or even by simple analysis,
we may be deceived into combinations the most artificial that can well be imagined.
Hence it is fortunate that every arrangement, thought to be natural, peremptorily
requires being brought to the test of analogical relations; and these, as we before
observed, are so many, and so severe, that if our interpretation of Nature will
stand such trials, we may confidently hope that no very glaring error has been
committed. For this purpose, let us first look to the five great the primary test by which we must try the orders of birds as
ANALOGIES OF THE MERULID-ffi.
Orders. Analogies. Families.
I nsessores . Feet formed both for perching and walking: omnivorous . . Merulirue.
R aptores . .Bill with a prominent tooth, & abruptly hooked: insectivorous . Myotherinae.
N atatores . Feet remarkably short . . . . . . . Brachypodin<B.
G rallatores. Wings long, pointed ; tail short: feed on soft substances . . Orwlince.
R asores . . Bill horny, hard, generally entire; feet very strong . . Crateropodinre.
The analogies in the two first columns are sufficiently evident: the third also
is satisfactory; the fourth is somewhat obscure; but the fifth is so particularly
beautiful, that it deserves further illustration. The short convex wings; the
broad, spreading tail; great difficulty in flight; a size superior to all others in
their respective circles, are the typical distinctions of these two groups ; even the
nostrils are formed upon the same principle; the membrane, by which the aperture
; is defended, and which in other birds is soft and pliable, in these assumes
the appearance of a hard scale, as if covered by a prolongation of the horny substance
of the beak. The loud, harsh, and disagreeable notes of both groups is
another singular point of resemblance, which almost completes the picture.
We next proceed to compare our groups with those of the tribes of Insessores.
C onirostres . Wings lengthened; bill gradually arched, slightly notched. Merulinee.
D entirostres. Bill abruptly hooked, with a prominent tooth . . . . . .Myotherinae.
F issirostres . Feet very short; rictus bristled: insectivorous.................Brachypodince.
T enuirostres . Feet short; rictus smooth: nectarivorous or frugivorous Oriolince.
S cansores . . Claws acute, formed for clinging to vegetables . . . . Crateropodvnte.
The analogies of the Orioles, scarcely perceptible when viewed in direct reference
to the Grallatores, now become more satisfactory. These birds, with the whole
of the Tenuirostres, are remarkable for the soft and delicate nature of their food;
and both, in unison with such habits, have the rictus entirely smooth. The Tem i-
rostres sip the nectar of flowers; the Oriolinw feed upon the fruits. The reader
may have remarked, that some peculiar habits of the Crateropodince could not be
explained by their analogy to the Rasores; the latter living in plains, and seldom
perching, whereas the former are scarcely ever seen upon the groundbut this
is at once explained by their relation to the Scansores; both groups being, in
different degrees, scansorial, and living on the upright stems of vegetables.