_J. Gould and H. C. Richter del et lith._ _Hullmandel & Walton Imp._
]
CUCULUS INORNATUS, _Vig. & Horsf._
Unadorned Cuckoo.
_Cuculus inornatus_, Vig. and Horsf. in Linn. Trans., vol. xv. p. 297.
—— _albostrigatus_, Ib., p. 298. young.
_Dju-dȕr-run_, Aborigines of Western Australia.
_Greater Cuckoo_ of the Colonists.
The southern portion of Australia generally, and the island of Van
Diemen’s Land, are inhabited by this species of Cuckoo; to the latter
country, however, it is only a summer visitant, and a partial migration
also takes place in the adjacent portion of the continent, as is shown
by its numbers being much fewer during winter. Its migratory movement
seems to be regulated, as in most other instances, by the more or less
abundant supply of food necessary for its sustenance. It arrives in Van
Diemen’s Land in the month of September, and departs northward in
February. During the vernal season it is an animated and querulous bird,
and it may then be seen either singly, or two or more males engaged in
chasing each other from tree to tree. Its ringing whistling call, which
consists of a succession of running notes, the last and highest of which
are several times rapidly repeated, is often uttered while the bird is
at rest among the branches, and also occasionally while on the wing. Its
food consists of caterpillars, _Phasmidæ_ and coleopterous insects,
which are generally procured among the leafy branches of the trees, and
in searching for which the bird displays considerable activity, and
great power of traversing the smaller limbs. When desirous of repose
after feeding, it perches on the topmost dead branches of the trees, on
the posts and rails of the fences, or any other prominent site whence it
can survey all around. It is however by no means a shy bird, and but
little caution is required to approach within gun-shot. Its flight is
straight and rapid, and not unlike that of the _Cuculus canorus_, to
which it bears a close resemblance in everything except its note;
occasionally it mounts considerably above the tops of the trees, and it
is capable of sustaining a long-continued flight.
In respect to its reproduction it is strictly parasitic, devolving the
task of incubation on the smaller birds, many species of which are known
to be the foster-parents; among them may be enumerated the various
_Melithrepti_, _Ptiloti_, _Maluri_, _Acanthizæ_, &c. After the young has
left the nest and attained a considerable size, it is not unusual to see
it fed by two or more species at the same time; this I have witnessed
with my own eyes; the young Cuckoo, in fact, selects some low dead
branch in an open glade of the forest, from which it seldom moves during
the day, as a convenient situation for its various foster-parents to
supply it with food, for the procuring and supplying of which all the
smaller birds appear to have entered into a mutual compact.
The specimens of this bird from Western Australia are somewhat smaller,
and have the white marks of the tail less distinct than specimens from
Van Diemen’s Land, but these differences are too trivial to be regarded
as other than mere local variations. When fully adult the plumage is
nearly of a uniform brown, with the inner webs of the wing and
tail-feathers relieved by bars and markings of white; the immature
colouring on the contrary presents a variegated and very diversified
character, which, owing to the constant change taking place, cannot be
described so as to render it clear to my readers. When the young leaves
the nest, the throat, face and shoulders are black, the feathers of the
remainder of the body crossed and spotted with buff; the black colouring
gradually gives place to the grey of the under surface, while the buffy
marks of the upper surface are retained even after the second or third
moult; it breeds in this state, and it is doubtful whether in the female
it is ever entirely cast off.
The stomachs of those dissected were found to be capacious, membranous,
and thickly lined with hair.
The egg is about seven-eighths of an inch long by five-eighths broad,
and is of a cream-colour speckled all over with markings of brown.
The adult male has the head, neck and all the under surface brownish
grey, with a streak of dark brown down the sides of the neck; all the
upper surface olive-brown, becoming much darker on the wings and tail;
basal portion of the inner webs of the primaries broadly barred with
white; tail-feathers barred on the margins of both webs with white,
slightly on the outer and deeply on the inner; all the feathers tipped
with white, and with a mark of white on the stem near the tip, this mark
being very small on the central tail-feather, and gradually increasing
on the lateral feathers until on the outer it forms a band; under-irides
very dark brown; eyelash yellow; gape and inside of the mouth rich deep
orange; feet olive.
The female differs in having the upper surface mottled with buff and
rufous, in having a triangular spot of reddish buff at the extremity of
each of the wing-coverts, and the markings of the tail buff instead of
white; all which markings may in very old birds give place to a style of
colouring similar to the male.
The young, independently of the differences pointed out above, has the
feet yellowish olive, the soles of the feet yellow; the bill yellowish
olive, the corner of the mouth and the tip of the bill being more yellow
than the rest of that organ; irides greyish brown.
The figures represent the two sexes of the natural size.
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