A History of the Birds of New Zealand.
Cabalus Modestus. — (Hutton’s Rail.)
Rallus modestus, Hutton, Ibis, 1872, p. 247.
Rallus dieffenbachii (young), Buller, Birds of New Zealand, 1st ed. p. 180 (1873).
Cabalus modestus, Hutton, Trans. N.-Z. Inst. vol. vi. p. 108 (1874) *
Cabalus dieffenbachii (young), Sharpe, App. Voy. Ereb. and Terror, p. 29 (1875).
Ad. olivascenti-brunneus, unicolor, plumis quibusdam interscapulii et tectricibus alarum majoribus paucis indistinctè fulvo fasciatim terminatis: supracaudalibus fulvo magis distinctè transfasciatis: facie laterali vix cinerascente: gutture sordidè cinereo, brunnescente obscurato: corpore reliquo subtùa brunneo, dorso concolore, sed angustè et magis distinctè fulvo transfasciato: rostro et pedibus pallidè brunneis: iride pallidè bruanneâ.
Adult. General plumage dull olive-brown, plumbeous at the base; throat greyish, each feather tipped with brown; feathers of the breast narrowly fringed with pale fulvous; those covering the upper part of abdomen and sides of the body, as well as the under tail-coverts, crossed by two narrow bars of the same colour; the first three primaries very faintly barred with reddish fulvous; tail-feathers, rump, and thighs obscurely freckled with fulvous. Irides, bill, and legs light brown. The plumage is very soft in texture, and the markings have the indeterminate character peculiar to young Rails.
Young. Covered with thick down of uniform brownish black.
This small Ocydromine form (which I treated in my former edition as the young of Cabalus dieffenbachii) was obtained by Mr. Henry Travers in the small island of Mangare (one of the Chatham Isles) in 1872; and Mr. Walter Hood informs me that it may still be obtained there, although difficult to procure, owing to its semi-nocturnal habits.
Prof. Hutton writes:—“Both the birds obtained by Mr. H. Travers were full-grown, one accompanied by her young one, and the other containing well-developed ova; they were both exactly alike in colour and dimensions, in neither of which do they show any approach to the colour and dimensions of R. dieffenbachii, as may be seen by comparing descriptions of the two; while in all known Rails the young soon acquire a plumage approaching in colour to that of the adult, and always attain their adult plumage before breeding. In its body, tail, wings, legs, and feet. C. modestus is a smaller bird than R. dieffenbachii, while the bills of the two are of nearly the same length; but in all Rails the legs and feet attain the full size very early, and long before the bill acquires its full length.”
* I have been favoured with the following interesting note:—“I have found the MS. of a paper all but completed, but never published, ‘Oil a comparison of the skeletons of Cabalus (= Rallus) modestus and Rallus philippensis’; and I take the present opportunity, through Sir Walter Buller’s kindness, of adding this footnote in support of the very distinctive characters of the bird in question—Cabalus modestus, Hutton. In the MS. above referred to I incidentally alluded to ornithologists’ recognized genera, which sometimes, when critically examined by the light of their osteology, do not furnish convincing data of stable bony characters in support of their attributed generic rank. In the instance of the Rail here mentioned, I then wrote:—’In anticipation of what follows as a matter of fact, I shall adduce proofs of differentiation such as not only indicate specific separation, but warrant generic relegation.’ I then give proofs of the bird being an adult, or nearly so, and of its being relatively flightless. Then followed comparisons of the bones &c., whereof I may mention, as an epitome of results and as the drawings elucidate, that trenchant distinctions obtain in the sternum and furcula, in the pelvis, and in the cranium and mandible, &c. The octavo plate of illustrations thereof has been lying finished since 1874; and at the recommendation of Sir W. Buller I intend forwarding the same with a revision of the MS. to date to the New Zealand Institute, in whose publications first notice of the bird appeared.”—James Murie..