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A History of the Birds of New Zealand.

Origin of the New-Zealand Avifauna

Origin of the New-Zealand Avifauna.

I have already said enough about the ancient and existing forms of bird-life in New Zealand to convince the most casual reader that we have within this comparatively small area a very remarkable ornithological province. In some respects it is quite unique, and, taken altogether, it is perhaps, to the student of biological history, the most interesting insular district on the face of our globe. In his admirable work on ‘The Geographical Distribution of Animals,’ Mr. Wallace has given, in a large woodcut, an ideal scene in New Zealand, representing some of its more singular forms. Referring to this, he says, “no country on the globe can offer such an extraordinary set of birds as are here depicted”; and in his elaboration of the subject, he has thrown more light than any previous writer on the origin and development of these peculiar ornithic types.

Looking to the fragmentary character of the New-Zealand fauna generally—the almost total absence of Mammalia and Amphibia, the phenomenal development of wingless birds that existed till quite recent times and are now represented by the various species of Apteryx, the highly specialized forms of non-volant Rails, besides the many other endemic genera of land-birds, and the great paucity of reptiles and insects—we must conclude that it is but the remnant of an ancient fauna, perhaps the most ancient in the world, which formerly occupied a very much wider area of the earth’s surface.

Professor Newton, in his Address to the British Association last year, called the attention of naturalists generally to the extreme interest which attaches to every portion of this unique fauna. Remarking on its origin and development he says:—“One thing to guard against is the presumption page xlix that the fauna originated within its present area, and has been always contained therein. Thus I take it that the fauna which characterizes the New-Zealand Region—for I follow Professor Huxley in holding that a Region it is fully entitled to be called—is the comparatively little changed relic and representative of an early fauna of much wider range; that the characteristic fauna of the Australian Region exhibits in the same way that of a later period; and that of the Neotropical Region of one later still.” He points out that the indigenous species are with scarcely an exception peculiar to the country, and from every scientific point of view of the most instructive character; and he urges the importance of their closest study, because the Avifauna is now being fast obliterated by colonization and other agencies, and with it will pass into oblivion, unless faithfully recorded by the present generation, a page of the world’s early history full of scientific interest.

The biological problems which the peculiar fauna and quasi-tropical flora of New Zealand suggest can only be met and reasonably explained on the hypothesis of a former land-connection between these islands and the northern or tropical portion of Australia; the severance, by submersion of the intervening land, having taken place at a period anterior to the spread of Mammalia over this portion of the earth’s surface. Mr. Wallace has, I think, made it perfectly clear that this ancient land-connection was with North Australia, New Guinea, and the Western Pacific Islands, rather than with the temperate regions of Australia. At p. 443 of his ‘Island Life’ he gives a reduced map showing the depth of the sea around Australia and New Zealand, as established by the most recent soundings. From this it is manifest, as he points out, that there is a comparatively shallow sea, or, in other words, a submarine bank, at a depth of less than 1000 fathoms, indicating the additional land-area that would be produced if the sea-bottom were elevated 6000 feet. This submerged plateau, if we may so term it, presents a remarkable conformation, extending in a broad mass westward and then sending out two great arms, one reaching to beyond Lord Howe’s Island, while the other stretches over Norfolk Island to the great barrier reef, thus forming the required connection with tropical Australia and New Guinea. It is argued that the ancient land-connection thus indicated, with perhaps, at a still more remote epoch, a connection with the great Southern continent by means of intervening lands and islands, will explain many of the difficult zoological problems that New Zealand presents.

This theory, while it accounts for the introduction into New Zealand by a north-western route, in very ancient times, of the Struthious type of birds, from which all the known species of Dinornis and Apteryx may have descended, explains too the tropical character of much of the New-Zealand flora, which is somewhat anomalous considering the temperate climate of New Zealand as we know it. Mr. Wallace states, as the result of careful research, that there are in New Zealand thirty-eight thoroughly tropical genera of plants, thirty-three of which are found in Australia, and, with a very few exceptions, in the northern or tropical portions only. To these may be added thirty-two more genera of plants which, though chiefly developed in temperate Australia, extend also into the tropical or subtropical portion of it, and which, it may reasonably be inferred, reached New Zealand by the same route. But to make this line of reasoning perfectly intelligible, it ought to be mentioned that the geological history of Australia shows it to have been for an immense period of time divided into an Eastern and a Western island, in the latter of which only the largely peculiar flora of temperate Australia—distinguished by its Eucalypti, Proteas, and Acacias—was developed, and where alone the marsupial Mammalia had their home. At this period, according to the above theory, New Zealand was in connection with the tropical portion of the Eastern island alone. This important geological fact will therefore account for the non-introduction into New Zealand, along with the page l ancestors of the Moas and Kiwis and the tropical plants referred to, of the marsupial fauna and the peculiar temperate flora so characteristic of Australia as we now know it*.

Sir Joseph Hooker, undoubtedly the ablest and most accomplished of living botanists, referring to an apparently insoluble enigma in the relations of the flora of New Zealand with that of Australia, thus expresses himself in the Introduction to his well-known ‘Flora of Australia’:—

“Under whatever aspect I regard the flora of Australia and New Zealand, I find all attempts to theorize on the possible causes of their community of feature frustrated by anomalies in distribution, such as I believe no two other similarly situated countries on the globe present. Everywhere else I recognize a parallelism or harmony in the main common features of contiguous floras, which conveys the impression of their generic affinity, at least, being affected by migration from centres of dispersion in one of them, or in some adjacent country. In this case it is widely different. Regarding the question from the Australian point of view, it is impossible in the present state of science to reconcile the fact of Acacia, Eucalyptus, Casuarina, Callitris, &c. being absent in New Zealand, with any theory of trans-oceanic migration that may be adopted to explain the presence of other Australian plants in New Zealand; and it is very difficult to conceive of a time or of conditions that could explain these anomalies, except by going back to epochs when the prevalent botanical as well as geographical features of each were widely different from what they are now. On the other hand, if I regard the question from the New-Zealand point of view, I find such broad features of resemblance and so many connecting links that afford irrefragable evidence of a close botanical connection, that I cannot abandon the conviction that these great differences will present the least difficulties to whatever theory may explain the whole case.”

It will be seen that the theory of which an outline has been given, while accounting in a rational manner for the marked peculiarities of the New-Zealand fauna, offers at the same time a probable solution of some of the strange anomalies of its flora in relation to that of Australia.

Mr. Wallace has explained that, in zoology, discontinuity in the areas of distribution must be accepted as an indication of antiquity, and that the more widely the fragments are scattered the more ancient we may, as a rule, take the parent group to be. “Thus the marsupials of South America and Australia are connected by forms which lived in North America and Europe; the camels of Asia and the llamas of the Andes had many extinct common ancestors in North America; the lemurs of Africa and Asia had their ancestors in Europe, as did the Trogons of South America, Africa, and

* “If we examine the geological map of Australia, we shall see good reason to conclude that the eastern and the western divisions of the country first existed as separate islands, and only became united at a comparatively recent epoch. This is indicated by an enormous stretch of Cretaccous and Tertiary formations extending from the Gulf of Carpentaria completely across the continent to the mouth of the Murray River. During the Cretaceous period, therefore, and probably throughout a considerable portion of the Tertiary epoch, there must have been a wide arm of the sea occupying this area, dividing the great mass of land on the west—the true seat and origin of the typical Australian flora—from a long but narrow belt of land on the east, indicated by the continuous mass of Secondary and Palæozoic formations already referred to, which extend uninterruptedly from Tasmania to Cape York. Whether this formed one continuous land, or was broken up into islands, cannot be positively determined; but the fact that no marine Tertiary beds occur in the whole of this area renders it probable that it was almost, if not quite, continuous, and that it not improbably extended across to what is now New Guinea. At this epoch, then, Australia would consist of a very large and fertile western island, almost or quite extra-tropical, and extending from the Silurian rocks of the Flinders range in South Australia to about 150 miles west of the present west coast, and southward to about 350 miles south of the Great Australian Bight. To the east of this, at a distance of about 250 or 400 miles, extended, in a north and south direction, a long but comparatively narrow island, stretching from far south of Tasmania to New Guinea; while the crystalline and Secondary formations of Central North Australia probably indicate the existence of one or more large islands in that direction.”—Island Life.

page li tropical Asia. But besides this general evidence, we have direct proof that the Struthious birds had a wider range in past times than now. Remains of extinct Rheas have been found in Central Brazil*, and those of Ostriches in North India, while remains believed to be of Struthious birds are found in the Eocene deposits of England; and the Cretaceous rocks of North America have yielded the extraordinary toothed bird, Hesperornis, which Professor O. Marsh declares to have been a ‘carnivorous swimming Ostrich.’ As to the second point, we have the remarkable fact that all known birds of this group have not only the rudiments of wing-bones, but also the rudiments of wings, that is, an external limb bearing rigid quills or largely developed plumes. In the Cassowary these wing-feathers are reduced to long spines like porcupine-quills, while even in the Apteryx the minute external wing bears a series of nearly twenty stiff quill-like feathers. These facts render it probable that the Struthious birds do not owe their imperfect wings to a direct evolution from a reptilian type, but to a retrograde development from some low form of winged birds, analogous to that which has produced the Dodo and the Solitaire from the more highly developed Pigeon type. Professor Marsh has proved that, so far back as the Cretaceous period, the two great forms of birds—those with a keeled sternum and fairly developed wings and those with a convex keel-less sternum and rudimentary wings—already existed side by side; while in the still earlier Archœopteryx of the Jurassic period we have a bird with well-developed wings, and therefore probably with a keeled sternum. We are evidently, therefore, very far from a knowledge of the earlier stages of bird-life, and our acquaintance with the various forms that have existed is scanty in the extreme; but we may be sure that birds acquired wings, and feathers, and some power of flight before they developed a keeled sternum, since we see that bats (with no such keel) fly very well. Since, therefore, the Struthious birds all have perfect feathers, and all have rudimentary wings, which are anatomically those of true birds, not the rudimentary fore legs of reptiles, and since we know that in many higher groups of birds—as the Pigeons and the Rails—the wings have become more or less aborted, and the keel and the sternum greatly reduced in size by disuse, it seems probable that the very remote ancestors of the Rhea, the Cassowary, and the Apteryx were true flying birds, although not perhaps provided with a keeled sternum or possessing very great powers of flight. But in addition to the possible ancestral power of flight, we have the undoubted fact that the Rhea and the Emu both swim freely, the former having been seen swimming from island to island off the coast of Patagonia. This, taken in connection with the wonderful aquatic Ostrich of the Cretaceous period discovered by Professor Marsh, opens up fresh possibilities of migration; while

* Reinhardt is of opinion that “the ancient and the modern Rhea are of one and the same species.”—Ibis, 1882, p. 332.

“See Buller’s illustration in Trans. N.-Z. Instit. vol. iii. plate 12 b. fig. 2.”

“Professor Marsh has shewn that there is good reason for believing that the power of flight was gradually acquired by Birds, and with that power would be associated the development of a keel to the sternum, on which the volant faculty so much depends, and with which it is so intimately correlated that, in certain forms which have to a greater or less extent given up the use of their fore-limbs, the keel, though present, has become proportionally aborted. Thus the Carinate type would, from all we can see at present, appear to have been evolved from the Ratite. This view receives further support from a consideration of the results of such embryological research as has already been made—the unquestionable ossification of the Ratito sternum from a smaller number of paired centres than the Carinate sternum, in which (with the doubtful exception of the Anatidæ) an additional, unpaired centre makes its appearance. Again, the geographical distribution of existing, or comparatively recent, Ratite forms points to the same conclusion. That these forms—Moa, Kiwi, Emeu and Cassowary, Rhea, and finally Ostrich—must have had a common ancestor nearer to them than is the ancestor of any Carinate form seems to need no proof. If we add to these the Æpyornis of Madagascar, the fossil Ratitæ of the Siwalik rocks, and the as yet but partially recognized Struthiolithus of Southern Russia, to say nothing of Gastornis, the evidence is stronger still. Seattered as these Birds have been or are throughout the world, it seems justifiable to consider them the survivals of a very ancient type, which has hardly undergone any essential modification since the appearance of Bird-life upon the earth—even though one at least of them has become very highly specialized.”—Prof. Newton in Enc. Brit. vol. xviii. pp. 43, 44.

page lii the immense antiquity thus given to the group and their universal distribution in past time, renders all suggestions of special modes of communication between the parts of the globe in which their scattered remnants now happen to exist altogether superfluous and misleading”*.

In his last-named work, Mr. Wallace divides all known islands into two classes, “Continental” and “Oceanic.” The former are always more varied in their geological formation—containing both ancient and recent stratified rucks—are rarely remote from a continent, and always contain some land Mammalia, also Amphibia and representatives of the other classes of animals in considerable variety. The “Oceanic” islands are usually far removed from continents and are always separated from them by very deep seas, are entirely without land Mammalia or Amphibia, but are generally well stocked with birds and insects and with some reptiles. Now New Zealand, which is undoubtedly “Continental” in its geological formation, also in the existence of the submerged bank already described connecting it in ancient times with North Australia and New Guinea, is as decidedly “Oceanic” in its zoological character, except as regards its wingless birds and the remarkable tuatara lizard (Sphenodon punctatum), which is said to constitute per se a distinct order of Reptilia of extreme antiquity. Mr. Wallace therefore terms New Zealand and the Celebes, where the conditions are somewhat similar, “Anomalous islands;” but Ancient continental may be perhaps a more convenient term.

As already explained, at the time of the supposed land-connection to the North-west, the Marsupial fauna could not have reached the eastern land now forming part of Australia; but it seems very probable that, at this early period, tropical Australia was tenanted by some Struthious kind of bird, perhaps volant in its character, which had reached this land, by way of New Guinea, through some ancient continental extension. If this theory, so well propounded by Mr. Wallace, is the true one, then the Cassowaries of New Guinea, the Emus of Australia, the extinct Dromornis of Queensland, and the Moas and Kiwis of New Zealand are doubtless the moditied descendants of this ancestral type. “The total absence (or extreme scarcity) of mammals in New Zealand obliges us to place its union with North Australia and New Guinea at a very remote epoch. We must either go back to a time when Australia itself had not yet received the ancestral forms of its present marsupials and monotremes, or we must suppose that the portion of Australia with which New Zealand was connected was then itself isolated from the mainland, and was thus without a mammalian population… But we must on any supposition place the union very far back, to account for the total want of identity between the winged birds of New Zealand and those peculiar to Australia, and a similar want of accordance in the lizards, the freshwater fishes, and the more important insect groups of the two countries. From what we know of the long geological duration of the generic types of these groups we must certainly go back to the earlier portion of the Tertiary period at least in order that there should be such a complete disseverance as exists between the characteristic animals of the two countries, and we must further suppose that, since their separation, there has been no subsequent union or sufficiently near approach to allow of any important inter-migration, even of winged birds, between them. It seems probable, therefore, that the Bampton shoal west of New Caledonia, and Lord Howe’s Island further south, formed the western limits of that extensive land in which the great wingless birds and other isolated members of the New-Zealand fauna were developed. Whether this early land extended eastward to the Chatham Islands and southward to the Macquaries we have no means of ascertaining; but as the intervening sea appears to be not more than 1500 fathoms deep,

* ‘Island Life,’ by Alfred Russel Wallace, pp. 451, 452.

page liii it is quite possible that such an amount of subsidence may have occurred. It is possible, too, that there may have been an extension northward to the Kermadec Islands, and even further to the Tonga and Fiji Islands, though this is hardly probable, or we should find more community between their productions and those of New Zealand. A southern extension towards the Antarctic continent at a somewhat later period seems more probable, as affording an easy passage for the numerous species of South American and Antarctic plants and also for the identical and closely allied freshwater fishes of these countries. The subsequent breaking up of this extensive land into a number of separate islands—in which the distinct species of Moa and Kiwi were developed—their union at a later period, and the final submergence of all but the existing islands, is a pure hypothesis, which seems necessary to explain the occurrence of so many species of these birds in a small area, but of which we have no independent proof”*.

In a preceding section I have already mentioned that, as a rule, the species of Dinornis which, in former times, inhabited the North Island were different in character from their contemporaries in the South Island, although the two areas of land are only separated by a strait scarcely eighteen miles across in its narrowest part. The same feature is maintained to the present day in the existing Avifauna, clearly showing that each island has a biological history of its own. Thus the Saddle-back (Creadion carunculatus) of the North is represented in the South by C. cinereus, a closely-allied species, but differing in the colour of its plumage; [unclear: Nth] Is thrushTurnagra hectori (now almost extinct) is represented by T. crassirostris, a species that will soon follow suit, although still plentiful in certain localities; the Weka (Ocydromus earli) is represented by several other closely-related species (O. australis, O. fuscus, and O. brachypterus) so closely resembling the northern bird both in appearance and habits that they are called “Woodhens” by the settlers of both islands and by them, as well as by the natives, are generally regarded as identical; the Popokatea (Clitonyx albicapilla) is represented by another species (C. ochrocephala) differing in colour, but so closely allied to it that the Maoris apply the same name to both; the Toutouwai (Miro australis), to which precisely the same remark applies, is represented by M. albifrons, and Glaucopis wilsoni by G. cinerea, distinguishable only by the colour of its ornamental wattles. Another case in point is furnished by the two representative species of Apteryx, the North Island bird being characterized by a different structure of plumage to that of the well-known Apteryx australis inhabiting the South Island. Till of late years it was believed that Apteryx oweni, which differs entirely from both of these species in the grey colour and mottled appearance of its plumage, was confined to the colder districts of the South Island; but in 1876 I communicated to the Wellington Philosophical Society the discovery of this bird near the summit of the Tararua mountains on the north side of Cook’s Strait, where it was found frequenting the stunted vegetation immediately below the snow-line. The existence of this species was entirely unknown to the Maoris of the North Island, and its occurrence under the conditions I have mentioned is a very interesting fact in geographical distribution.

Analogous cases of representative species in more or less widely separated areas are of frequent occurrence in other parts of the world. “The cause of this” (writes Mr. Wallace) “is very easy to understand. We have already shown that there is a large amount of local variation in a considerable number of species, and we may be sure that were it not for the constant intermingling and intercrossing of the individuals inhabiting adjacent localities this tendency to local variation would soon form distinct races. But as soon as the area is divided into two portions, the intercrossing is stopped,

* ‘Island Life,’ p. 454.

Trans. N.-Z. Instit. vol. viii. pp. 193–194.

page liv and the usual result is that two closely allied races, classed as representative species, become formed. Such pairs of allied species on the two sides of a continent, or in two detached areas, are very numerous; and their existence is only explicable on the supposition that they are descendants of a parent form which once occupied an area comprising that of both of them,—that this area then became discontinuous,—and, lastly, that, as a consequence of the discontinuity, the two sections of the parent species became segregated into distinct races or even species.”

In his ‘Geographical Distribution of Animals’ Mr. Wallace treats New Zealand and her satellites as forming a subregion of Australia. The Australian, or “great insular region of the earth,” is divided by him into four subregions, distinguished as the Austro-Malayan, Australian, Polynesian, and New Zealand. The last-named subregion is made to include Norfolk Island, Phillip and the Nepean Isles, Lord Howe’s Island and the Kermadec Isles on the north, the Chatham Islands on the east, the Auckland, Macquarie, Emerald, Campbell, Antipodes, and Bounty Islands on the south and south-east.

Other prominent writers on the subject have claimed for New Zealand full recognition as a separate biological province, quite distinct from Australia and every other region of the earth, My own study of the subject having brought me to the same conclusion, I propose to examine here, very briefly, the grounds upon which Mr. Wallace links New Zealand to Australia as contiguous sections of one biological region. He admits, of course, that there is a “wonderful amount of speciality,” but he contends that “the affinities of the fauna, whenever they can be traced, are with Australia or Polynesia.”

If we take Mr. Wallace’s own table of the geographical distribution we find, on a careful analysis, that out of twenty-eight families stated to be common to Australia and New Zealand, three are included in error, namely Sittidæ, Dicæidæ, and Pandionidæ, thus reducing the number to twenty-five. Of these, fifteen are admitted by him to be cosmopolitan, and may therefore be discharged from the present inquiry. Of the remaining ten, four belong to the Old World, four to the Oriental, Ethiopian, Austro-Malayan, and Polynesian regions respectively, and one highly specialized family, the Spheniscidæ, to the south temperate regions, leaving thus only one family, the Tit mouseParidæ, as restricted in its range to the two countries. This family is represented in New Zealand by a single genus, Certhiparus, about the true position of which there is considerable doubt, and this genus again is represented by a single species, so that, as regards the mere distribution of families, the argument altogether fails. Let us now examine the far more important question of identical or representative genera and species in the two countries, for this after all is the true test of a common origin. Of the twelve genera of Australian birds which he treats as belonging equally to New Zealand, it may be remarked that two (namely Graucalus and Acanthochœra), each of them represented by a single species, have only occurred in New Zealand as accidental stragglers, at very long intervals; that Tribonyx, as already explained at p. xiv, has never actually occurred in a wild state; and that Orthonyx and Hieracidea have, on further investigation of their characters, been replaced by two endemic genera, Clitonyx and Harpa. Of the remaining seven, two alone (Gerygone and Sphenœacus) are characteristic of Australia, the others ranging over a great part of the southern hemisphere; thus, Platycercus is spread over New Guinea and Polynesia, as well as Australia, Rhipidura extends to India, and Zosterops through Polynesia and the Malay Archipelago to India and Africa. Of the five species mentioned by Mr. Wallace as being identical in Australia and New Zealand, it may be mentioned that three (Acanthochæra carunculata, Graucalus melanops, and Hirundo nigricans) are among our rarest stragglers from abroad, and that the Shining Cuckoo (Chrysococcyx lucidus) is an page lv annual migrant to and from Australia: thus leaving only Zosterops cœrulescens to be accounted for, and this species has been sufficiently treated of already.

Mr. Wallace’s strongest point is the Family Meliphagidæ, which is a very typical and well-distributed Australian group. But accepting, as I think we must do, his theory of the introduction of the ancestral types into New Zealand by way of tropical Australia and New Guinea, it is easy to account for the presence of this peculiar form in both countries, inasmuch as the Meliphagidae have representatives as far north as the Sandwich Islands, whilst other members of the group are spread through the Austro-Malayan subregion, finding their extreme western limit in the Celebes. Supposing that the ancient type reached New Zealand by the north-western route, it then resolves itself into a mere question of time and “descent with modification.”

Dr. Otto Finsch, who has written several interesting papers on New-Zealand Ornithology, appears to me to exaggerate very much the importance of this feature, for he accepts it as a proof of “far more intimate connection with Australia than one would suppose from the geographical position of the two countries.” He is unable, however, to account for the absence of true Trichoglossi in New Zealand, seeing that this group is so strongly developed in the temperate parts of Australia.

It is a point of some significance that the Meliphagine genera in New Zealand are not very closely related to those of Australia, except in the case of Pogonornis, which approximates somewhat to Ptilotis, a decidedly subtropical genus. Apart from the true Honey-eaters, the only genera that Mr. Wallace specially refers to as related to peculiar Australian ones are Miro and Myiomoira (allied to Petrœca), Ocydromus (allied to Eulabeornis), and Hymenolœmus (allied to Malacorhynchus). It seems to me, therefore, that he has not succeeded in establishing a co-ordinate relation between the avifaunae of these so-called subregions of Australia.

It is worthy of remark also that, with the exception of the highly developed Meliphagidae, comprising four very distinct genera (and numbering altogether only five species), none of the New-Zealand families contain more than two genera, presenting a marked difference in this respect to the numerous subordinate groups among the birds of Australia.

Seeing that the Shining Cuckoo (Chrysococcyx lucidus) is met with in New Guinea, and probably further west, that it is likewise found in tropical Australia, and that it comes to us from the north, or north-west–for it always makes its appearance first at the extreme north–it is easy to understand that the migratory impulse has been inherited from time immemorial, and the more so as the closely-allied species (C, plagosus) is also a summer visitant to the temperate and southern portions of Australia. But it is very difficult to imagine why the Long-tailed Cuckoo (Eudynamis taitensis), which hibernates in the warm islands of the Pacific–the Friendly, Society, Marquesas, Fiji, and Samoa groups–ranging over more than 40° of longitude, should make its annual pilgrimage across 1500 miles of ocean to New Zealand*.

The Waders are, for the most part, cosmopolitan, and are therefore of little account when estimating the geographical relations of the avifauna.

* Mr. Wallace says, in his account of the Chatham Islands (‘Island Life,’ p. 454):—“It is stated that the Zosterops differs from that of New Zealand, and is also a migrant; and it is therefore believed to come every year from Australia, passing over New Zealand, a distance of nearly 1700 miles!” But this is evidently a lapsus calami, the bird intended being the Chrysococcyx. Prof. Hutton stated (Trans. N.-Z. Instit. vol. v. p. 225) that this happened in the case of C. plagosus; but I have shown elsewhere that he was wrong in his identification of the species, the Shining Cuckoo (C. lucidus) which annually visits the Chatham Islands being identical with the New-Zealand bird. Chrysococcyx plagosus, distinguished by its narrower bill, has never been met with in New Zealand, and it would be strange indeed if this Australian species had occurred in the Chatham Islands to the eastward.

page lvi

One of the most widely distributed species is the Eastern Golden Plover (Charadrius fulvus), which, at all times rare in New Zealand, is plentiful in Australia, and spreads itself over the Polynesian Islands and the Indian Archipelago, westward to Ceylon, and northward to Siberia and Kamtschatka, where it rears its young.

Several of our Ducks are common to Australia, but it is well known that this Order is a very diffuse one in all parts of the world. Our common Grey Duck (Anas superciliosa), for example, extends its range into Tasmania and Australia, over a large portion of Polynesia, and as far north as the Sandwich Islands; whilst the White-winged Duck (Anas gibberifrons) is met with, not only in Australia, but in New Caledonia and the Indian Archipelago. The genus Hymenoloemus, represented by our peculiar Mountain Duck, is closely related to an Australian one, and our Shoveller (Rhynchaspis variegata) is a representative species to that inhabiting Australia and Tasmania, the two forms being very closely allied. Two other Ducks, however (Dendrocygna eytoni and Nyroca australis) are so rare with us that they may fairly be regarded as Australian stragglers. Even where the species is peculiar to New Zealand, the genus to which it belongs may be a widely spread one: for example, Fuligula novæ zealandiæ belongs to a genus which has representatives in the northern parts of America, in Europe and in Asia, and our splendid Casarca variegata represents a genus which is almost cosmopolitan.

One of the most puzzling of these occurrences is the Little Bittern (Ardetta pusilla), which, although decidedly rare, has been met with on the west coast and in the southernmost part of the South Island. Both this and our common species (Botaurus pœciloptilus) are birds of feeble wing; yet they are identical with, the species inhabiting temperate Australia, showing that they must have preserved their individuality as species for a very long period of time. The same remark applies to our Porphyrio melanonotus, and, in a lesser degree, to Rallus philippensis and Ortygometra affinis, which are very closely related to R. pectoralis and O. palustris respectively.

When we come to compare our avifauna with that of the Polynesian “subregion” there is still less resemblance, for the only genera common to both are the two referred to above, whilst the only species mentioned by Mr. Wallace as identical is our other migratory Cuckoo (Eudynamis taitensis). It is true that he questions the fact of these Cuckoos being migratory at all, and endeavours to account for their disappearance in winter by suggesting that “in a country which has still such wide tracts of unsettled land, they may only move from one part of the islands to another.” But quite apart from the lengthened form of the wing in both of these Cuckoos, which at once proclaims them “birds of passage,” the fact of their seasonal arrival in and departure from our country, as fully recorded in my account of each species, is well attested, and forms an essential part of their natural history.

Besides the genera of occasional or accidental occurrence (Acanthochœra and Hirundo) and the migratory Cuckoo already mentioned, the only groups of land-birds common to New Zealand and Polynesia are Platycercus, Carpophaga, and Zosterops, and the widely spread genera Rhipidura, Halcyon, and Circus*

* It may be worth noting that I have remarked the following similarity between the names employed in the Fijian and Maori languages for the same or corresponding birds:—

Kawakawasa.=Kawekawea (Eudynamis taitensis).
Lulu.=Ruru (an. Owl).
Kaka (a kind of Parrot).=Kaka (Nestor meridionalis).
Toa (any fowl-like bird).=Moa (Dinornis).
Toro.=Toroa (an Albatros).
Kula (a red Parrot).=Kaka-kura.
page lvii

The Cormorants are evidently adapted by nature to a cold or temperate climate, for as we advance towards the Tropics they disappear, and it is said that not a single species is to be found in the whole of Polynesia.

In New Caledonia and the New Hebrides, which form a sort of transition ground into Australia proper and the Papuan group, we have the same genera, and in addition thereto, inhabiting New Caledonia, a flightless Rail, allied to the New-Zealand Woodhen.

The Chatham Islands to the east of New Zealand, the Auckland Islands, and the other scattered islets to the south and south-east are so obviously related to New Zealand geographically, besides coming within the political limits of the Colony, that I have included their birds in the present work. It is interesting to notice, however, that these islands nearly all contain one or more peculiar species, showing that the isolation has been of sufficiently long duration to allow of this development. Thus in the Chatham Islands and the adjacent islets there are seven peculiar species, namely, Anthornis melanocephala, Gerygone albofrontata, Miro traversi, Sphenœacus rufescens, Rallus diffenbachii, Cabalus modestus, and Phalacrocorax featherstoni.

In the Auckland Islands, lying about 300 miles to the south of New Zealand, the three species mentioned by Mr. Wallace as peculiar (Anthus aucklandicus, Platycercus aucklandicus, and P. malherbii) have been proved to have no existence as valid species; but, as already mentioned, this small area contains two species of Duck (Nesonetta aucklandica and Mergus australis) hitherto not met with elsewhere; also a Snipe (Gallinago aucklandica) and a species of Rail (Rallus- brachypus), both of which are supposed to be peculiar to these small islands.

From Macquarie Island, still further south, we have the handsome Phalacrocorax nycthemerus and possibly a new species of Rail; from Campbell Island, so far as our present knowledge extends, another fine Cormorant (P. magellanicus) and a peculiar Penguin; from the Snares the unique Eudyptes atrata, described by Prof. Hutton; and from Antipodes Island the interesting Ground-Parrakeet (Platycercus unicolor) lately discovered by Captain Fairchild. A small Hawk. received by me from Macquarie Island is undoubtedly the same as our Harpa ferox, and the Rail which Prof. Hutton has distinguished as Rallus macquariensis seems to me to be merely a local race of P. philippensis, if at all separable from that species. There can be no doubt, therefore, of the propriety of including even this remote island in the New-Zealand region.

The case is different, however, with the islands to the north of New Zealand. The instances mentioned by me at p. 24 of the present volume make it abundantly clear that at some period there was a land-connection with Lord Howe’s Island, Norfolk Island, and the Nepean group, and possibly with the Kermadec Islands * to the eastward; but, owing to the introduction from time to time of a colonist population, so to speak, from the nearer continent, the avifauna of these islands is decidedly more Australian than New Zealand. With the exception of Nestor productus and Notornis alba, all the species of land-birds inhabiting Norfolk Island and the Nepean group belong to Australian genera; and of the sixteen recorded species, all but three occur also in various parts of Australia.

The same remarks apply to Lord Howe’s Island lying midway between Norfolk Island and Australia. With the exception of Ocydromus sylvestris, all the birds belong to well known Australian

* Mr. J. F. Cheeseman, who accompanied the Annexation expedition to the Kermadec Islands last year, has lately communicated to the Linnean Society (through Sir Joseph Hooker) a report on the flora of these islands. He mentions incidentally that the land-birds found there, which were few in number, appeared to belong to New-Zealand species, but he doea not state what these birds were.

page lviii types, and the species themselves are identical, with the exception of Zosterops strenuus and Z. tephropleurus, both of which, strange to say, are peculiar to this small island.

To summarize the results, it may be mentioned that out of sixty-nine species of “land-birds” (excluding the Herons and Bitterns) only eleven have a wider range than New Zealand. Of these exceptions five are only accidental stragglers from Australia; two are annual migrants; and the remaining four are Zosterops cœrulesoens, Rallus philippensis, Ortygometra tabuensis, and Porphyrio melanonotus. But, what is even more remarkable still, out of thirty-four genera, after making a similar elimination to the above, not less than twenty-two are strictly endemic, showing at a glance how restricted is the character of the New-Zealand Avifauna.

That the Ornis of New Zealand may have been, from time to time, affected by casual immigration from Australia is probable enough, for, as we have seen, even during recent years, many individual cases of the kind have been recorded at irregular intervals; and it is rather matter for surprise, on this ground, that there is not a stronger family likeness, so to speak, between the indigenous birds of the two countries at the present day.