A History of the Birds of New Zealand.
Ocydromus Brachypterus. — (Buff Woodhen.)
Ocydromus brachypterus, Lafr. Mag. de Zool. 1842, pl. 42.
Ocydromus hectori, Hutton, Trans. N.-Z. Inst. vol. vi. p. 110 (1874).
Ocydromus brachypterus, Buller, Trans. N.-Z. Inst. vol. x. p. 214 (1878).
Ad. similis O. australi, sed pallidior: supracaudalibus et scapularibus nigricanti-brunneo conspicuè transfasciatis: pectore superiore lætè stramineo: pectore medio cinereo tincto: hypochondriis et subcaudalibus distinctè transfasciatis.
Adult. Of similar size to O. australis, but having the plumage of a more uniform buff or pale olivaceous brown colour, with the wings, sides of the body, and flanks more conspicuously barred with brownish black.
Young. There is a specimen in the Otago Museum, just fledged, in which the distinctive characters described above are sufficiently marked. On comparing it with a fledgling of Ocydromus australis this became the more apparent, the former having obscure barred markings on the flanks, which were entirely absent in the other.
Varieties. A specimen which I refer to this species, on account of the pronounced character of the barred markings on the wings, is a singular example of partial albinism; the entire plumage is pure white, slightly shaded with cream on the nape, excepting only the wing-feathers which are of the normal colours, and completely covered with transverse markings, the bars being very regular and distinct; the tail-feathers are like the body-plumage, pure white; bill whitish horn-colour, tinged with yellow at the base; legs and feet pale brown.
My late brother, Mr. John Buller, assured me that he invariably found the Alpine bird considerably larger in size than those inhabiting the plains, and of a much lighter colour.
A specimen brought by Mr. Henry Travers from the interior of the Marlborough, Province has the general plumage of a yellowish-buff colour, very obscurely marked and spotted with brown; and among those obtained by Sir George Grey in the Otago hills, for the purpose of stocking the Kawau Island, I observed that one (apparently a young bird) had similar plumage, although it was more distinctly banded on the sides and flanks. Sir G. Grey informed me that these birds were taken by himself at an elevation of 6000 feet, where they were found concealed under the tussocks or hiding among the loose rocks, the assistance of a dog being required to dislodge them. A specimen in my collection has the whole of the upper surface light fulvous shaded with brown, each feather having a subterminal spot of that colour; the primaries and secondaries are dark rufous brown barred with black, and the soft overlapping feathers are fulvous, stained more or less with rufous and barred with black in their middle portion, margined and spotted towards the end with cream-yellow; the throat, fore neck, and breast pale cinereous brown, mixed with fulvous on the crop; the lower parts dull cinereous brown, fasciated on the sides and flanks with narrow markings of fulvous.
Professor Hutton regards this bird as distinct (Ocydromus troglodytes, Wagler), and says of it:—“The distinguishing marks of this species are its large size, the general olivaceous tints of its plumage, the middle tail-feathers having generally a black streak down the shaft, and the primary feathers of the wing tapering towards the point.”
Obs. All the Woodhens in the Canterbury Museum (excepting O. earli and O. fuscus) appear to me to belong to O. australis. There is one marked (in Prof. Hutton’s handwriting) O. troglodytes, but it does not differ from the rest in any essential respect, although it is an unusually large example, and pale in all its colours.page 120
It is with some hesitation that I accord specific rank to this bird, for although my collection contains some beautifully marked specimens, they intergrade to such an extent that it is extremely difficult to draw any distinct line between this species and O. australis.
I have thought it best, however, to give a figure and description of my most characteristic specimen, and to leave ornithologists to choose for themselves whether they will recognize this form as distinct, or as being only an extreme variety of the highly variable South-Island Woodhen.
My own revision of the group was thus stated in a paper which I read before the Wellington Philosophical Society in January 1878 *:—
“Although as a group the limits of the genus Ocydromus are sufficiently well defined, considerable difficulty has been experienced in determining the species. Every naturalist who has studied the subject appears to have arrived at some different conclusion as to the number of constant forms; and where the variances as to size and plumage are so well maintained it is difficult to avoid drawing specific distinction. If, however, it can be shown that all these extreme forms graduate in a series, or, in óther words, run into one another, it becomes impossible to find any fixed aberrant characters. Without professing to be able yet to place the matter beyond all dispute, I venture to think that the series of specimens which I have the honour to exhibit this evening affords pretty strong evidence that several of the so-called species in the South Island must be united under the name of Ocydromus australis.
“In my ‘Birds of New Zealand’ (1st ed.), I admitted only three well-ascertained species as inhabiting New Zealand—namely, O, earli, O. australis, and O. fuscus. I mentioned in the introduction to that work that, although Dr. Finsch recognized a fourth (O. troglodytes, Gmel.), I was unable to draw any specific line. Nevertheless, I pointed out very fully, in my account of the South-Island Woodhen, the great variation both as to size and markings which that species exhibits, especially among birds from different localities.
“Captain Hutton, in an article on the New-Zealand Woodhens, read before this Society † in September, 1873, agreed with Dr. Finsch in admitting O. troglodytes, and added two more species of his own under the names of O. hectori and O. finschi. He further described a ‘variety or immature’ example of this last-named species, which he suggests my ‘possibly be identical with Gallirallus brachypterus, Lafr.’
“Dr. Finsch, in a paper ‡ written the year following, professes to identify Ocydromus troglodytes with the O. australis of my text, page 170, but not the plate; of O. hectori he remarks, ‘I consider this a good species after having compared a typical specimen;’ and of O. finschi he flays that, having examined the type, he considers it a good species, although not without some suspicion that it may prove to be a variety of O. fuscus. He confuses Ocydromus australis, Sparrm., with the well-known O. earli; and with respect to the latter in Hutton’s list, he makes the following singular statement:—‘Dr. Buller, in his great work, unfortunately does not mention the typical specimen of O. earli, Gray, and not having compared it myself, I am unable to make out whether the true earli is, indeed, the bright cinnamon-red bird as Captain Hutton and I believe, or whether it is the same as O. australis, figured under the name of earli by Dr. Buller’ §. Captain Hutton, on the other hand, writes me:—‘I am sure that you are right about the identification of O. earli, and I don’t understand how Finsch thinks otherwise’ ∥.
“Baron A. von Hügel, who has lately been on a scientific tour through the colonies, writes thus in ‘The Ibis’ ¶:—Of New-Zealand things I have got a very fair collection—some 300 specimens already. Ocydromus I have, of course, gone in for, and have a lot of notes about it. I don’t believe in more than three good species—O. australis (with endless varieties), O. fuscus, and O. earli. The last two are difficult to procure, although I shall doubtless get a series of the latter in the North Island; but of O. australis one could got a shipload in a very short time. I have got a splendid series, showing every age from embryo to adult, and varieties to perfection.’ It will be seen, therefore, that the Baron, who comes to the subject with a totally unprejudiced mind, adopts my published division of the species in a very positive manner.
“If, on further investigation, it should be found necessary to add a fourth species, this must be Ocydromus brachypterus, Lafresnaye; for Dr. Finsch, who appears to have examined the type specimen, affirms distinctly ** that it is the same as Hutton’s O. hectori; and Captain Hutton himself admits that this is ‘very probable’ ††. This is of course the bird referred to at page 171 of my ‘Birds of New Zealand’ (1st ed.), in the following passage:—‘Dr. Hector informs me that on all the high mountains of the Otago province he met with a “cream-coloured variety,” very readily distinguishable from the common bird. Mr. Buchanan confirms this observation, and states that on the Black Peak, at an elevation of 6000 feet, he found this light variety very abundant, but none of the other birds; the former, indeed, were so numerous as to prevent his getting any sleep.’ It seems unfortunate that, in obedience to the law of priority in nomenclature, we must sink a name, very fittingly bestowed, in favour of brachypterus, which expresses no distinguishing specific character, being equally appropriate to all the forms of Ocydromus.”
* Trans. N.-Z. Inst. vol. x. pp. 213–216.
† Op. cit. vi. p. 110.
‡ Ibid. vii. pp. 226–236.
§ Ibid. vii. p. 231.
∥ Id. ibid. ix. p. 330.
¶ ‘The Ibis,’ 1875, p. 393.
** Trans. N.-Z. Inst. viii. p. 202.
†† Loc. cit. ix. p. 330.