The sexes are so precisely similar in outward appearance, that dissection must be resorted to to distinguish the one from the other.
Forehead buff, each feather edged with brown; all the upper surface and wings brown, tinged with olive; tail reddish olive, crossed near the tip by a narrow band of black; throat and chest greyish white, each feather margined with black, giving that part a mottled appearance; flanks, abdomen and under tail-coverts buff; irides brownish red; bill dark brown; feet brown.
The Plate represents two individuals of the natural size.
ACANTHIZA DIEMENENSIS: Gould.
J. Gould and H. C. Richter del et lith. C. Hullmandel Imp.
ACANTHIZA DIEMENENSIS, Gould.
Tasmanian Acanthiza.
Acanthiza Diemenensis, Gould in Proc. of Zool. Soc., Part V. p. 146; and in Syn. Birds of Australia, Part IV.
Brown-tail, Colonists of Van Diemen’s Land.
I believe this species, like the Acanthiza Ewingii, to be peculiar to Van Diemen’s Land, over the whole of which country it is rather numerously dispersed, and where it inhabits forests and open woodlands, but evinces a preference to low and shrub-like trees rather than to those of a higher growth. It also frequents the gardens and shrubberies of the colonists; it is consequently one of the commonest and one of the best known birds of the island. Active and sprightly in its actions, it prys about the foliage with the most scrutinizing care in search of insects and their larvæ, which constitute its sole food. It frequently utters a rather loud harsh note, which is sometimes changed for a more full and clear strain; still its vocal powers are by no means conspicuous. It has a much more lengthened bill, and is altogether a larger bird than the Acanthiza pusilla, whose habitat seems restricted to the south-eastern portion of the Australian continent. The plumage of the sexes is alike, and their size and general appearance so similar, that without the aid of dissection it is impossible to distinguish them. The nest of this little bird, which is usually built in a low shrub, is rather a dense structure, being formed of grasses, fibrous roots and the inner bark of trees, warmly lined with feathers; it is of a globular form, with a small hole in the side near the top for an entrance, and is very similar in appearance to that of the Common Wren, Troglodytes Europæus. The eggs are four or five in number, of a beautiful pearly bluish white, sprinkled and spotted with reddish brown. In some instances the spots form a zone round the larger end. The medium length of the eggs is eight lines and a half, and breadth six lines.
Independently of the task of incubating its own offspring, this species very frequently has to perform the additional labour of hatching and rearing the young of the Bronze Cuckoo (Chalcites lucidus), whose single egg or young is often found in the nest. It is a very early breeder, commencing in August and continuing until January, during which period two or three broods are generally reared by each pair.