[100] This view was, I believe, first put forth by myself in a paper read before the Geological Section of the British Association in 1869, and subsequently in an article in Nature, Vol. I. p. 454. It was also stated by Mr. S. B. J. Skertchley in his Physical System of the Universe, p. 363 (1878); but we both founded it on what I now consider the erroneous doctrine that actual glacial epochs recurred each 10,500 years during periods of high excentricity.
[101] Explication d'une seconde édition de la Carte Géologique de la Terre (1875), p. 64.
[102] For most of the facts as to the zoology and botany of these islands, I am indebted to Mr. Godman's valuable work—Natural History of the Azores or Western Islands, by Frederick Du Cane Godman, F.L.S., F.Z.S., &c., London, 1870.
[104] Some of Mr. Darwin's experiments are very interesting and suggestive. Ripe hazel-nuts sank immediately, but when dried they floated for ninety days, and afterwards germinated. An asparagus-plant with ripe berries, when dried, floated for eighty-five days, and the seeds afterwards germinated. Out of ninety-four dried plants experimented with, eighteen floated for more than a month, and some for three months, and their powers of germination seem never to have been wholly destroyed. Now, as oceanic currents vary from thirty to sixty miles a day, such plants under the most favourable conditions might be carried 90 X 60 = 5,400 miles! But even half of this is ample to enable them to reach any oceanic island, and we must remember that till completely water-logged they might be driven along at a much greater rate by the wind. Mr. Darwin calculates the distance by the average time of flotation to be 924 miles; but in such a case as this we are entitled to take the extreme cases, because such countless thousands of plants and seeds must be carried out to sea annually that the extreme cases in a single experiment with only ninety-four plants, must happen hundreds or thousands of times and with hundreds or thousands of species, naturally, and thus afford ample opportunities for successful migration. (See Origin of Species, 6th Edition, p. 325.)
[105] The following remarks, kindly communicated to me by Mr. H. N. Moseley, naturalist to the Challenger, throw much light on the agency of birds in the distribution of plants:—"Grisebach (Veg. der Erde, Vol. II. p. 496) lays much stress on the wide ranging of the albatross (Diomedea) across the equator from Cape Horn to the Kurile Islands, and thinks that the presence of the same plants in Arctic and Antarctic regions may be accounted for, possibly, by this fact. I was much struck at Marion Island of the Prince Edward group, by observing that the great albatross breeds in the midst of a dense, low herbage, and constructs its nest of a mound of turf and herbage. Some of the indigenous plants, e.g. Acæna, have flower-heads which stick like burrs to feathers, &c., and seem specially adapted for transposition by birds. Besides the albatrosses, various species of Procellaria and Puffinus, birds which range over immense distances may, I think, have played a great part in the distribution of plants, and especially account, in some measure, for the otherwise difficult fact (when occurring in the tropics), that widely distant islands have similar mountain plants. The Procellaria and Puffinus in nesting, burrow in the ground, as far as I have seen choosing often places where the vegetation is the thickest. The birds in burrowing get their feathers covered with vegetable mould, which must include spores, and often seeds. In high latitudes the birds often burrow near the sea-level, as at Tristan d'Acunha or Kerguelen's Land, but in the tropics they choose the mountains for their nesting-place (Finsch and Hartlaub, Orn. der Viti- und Tonga-Inseln, 1867, Einleitung, p. xviii.). Thus, Puffinus megasi nests at the top of the Korobasa basaga mountain, Viti Levu, fifty miles from the sea. A Procellaria breeds in like manner in the high mountains of Jamaica, I believe at 7,000 feet. Peale describes the same habit of Procellaria rostrata at Tahiti, and I saw the burrows myself amidst a dense growth of fern, &c., at 4,400 feet elevation in that island. Phaethon has a similar habit. It nests at the crater of Kilauea, Hawaii, at 4,000 feet elevation, and also high up in Tahiti. In order to account for the transportation of the plants, it is not of course necessary that the same species of Procellaria or Diomedea should now range between the distant points where the plants occur. The ancestor of the now differing species might have carried the seeds. The range of the genus is sufficient."
[106] Nature, Vol. VI. p. 262, "Recent Observations in the Bermudas," by Mr. J. Matthew Jones.
[107] "The late Sir C. Wyville Thomson was of opinion that the 'red earth' which largely forms the soil of Bermuda had an organic origin, as well as the 'red clay' which the Challenger discovered in all the greater depths of the ocean basins. He regarded the red earth and red clay as an ash left behind after the gradual removal of the lime by water charged with carbonic acid. This ash he regarded as a constituent part of the shells of Foraminifera, skeletons of Corals, and Molluscs, [vide Voyage of the Challenger, Atlantic, Vol. I. p. 316]. This theory does not seem to be in any way tenable. Analysis of carefully selected shells of Foraminifera, Heteropods, and Pteropods, did not show the slightest trace of alumina, and none has as yet been discovered in coral skeletons. It is most probable that a large part of the clayey matter found in red clay and the red earth of Bermuda is derived from the disintegration of pumice, which is continually found floating on the surface of the sea. [See Murray, "On the Distribution of Volcanic Débris Over the Floor of the Ocean;" Proc. Roy. Soc. Edin. Vol. IX. pp. 247-261. 1876-1877.] The naturalists of the Challenger found it among the floating masses of gulf weed, and it is frequently picked up on the reefs of Bermuda and other coral islands. The red earth contains a good many fragments of magnetite, augite, felspar, and glassy fragments, and when a large quantity of the rock of Bermuda is dissolved away with acid, a small number of fragments are also met with. These mineral particles most probably came originally from the pumice which had been cast up on the island for long ages (for it is known that these minerals are present in pumice), although possibly some of them may have come from the volcanic rock, which is believed to form the nucleus of the island." The Voyage of H.M.S. Challenger, Narrative of the Cruise, Vol. I. 1885, pp. 141-142.
[108] Four bats occur rarely, two being N. American, and two West Indian Species. The Bermuda Islands, by Angelo Heilprin, Philadelphia, 1889.
[109] Fourteen species of Spiders were collected by Prof. A. Heilprin, all American or cosmopolitan species except one, Lycosa atlantica, which Dr. Marx of Washington describes as new and as peculiar to the islands. (Heilprin's The Bermudas, p. 93.)
[110] Mr. Theo. D. A. Cockerell informs me that there are two slugs in Bermuda of which specimens exist in the British Museum,—Amalia gagates Drap. common in Europe, and Agriolimax campestris of the United States. Both may therefore have been introduced by human agency. Also Vaginulus Morelete var. schivelyæ which seems to be a variety of a Mexican species; perhaps imported.
[111] "Notes on the Vegetation of Bermuda," by H. N. Moseley. (Journal of the Linnean Society, Vol. XIV., Botany, p. 317.)
[112] Gigantic Land Tortoises Living and Extinct in the Collection of the British Museum. By A. C. L. G. Günther, F.R.S. 1877.
[113] The following list of the beetles yet known from the Galapagos shows their scanty proportions and accidental character; the forty species belonging to thirty-three genera and eighteen families. It is taken from Mr. Waterhouse's enumeration in the Proceedings of the Zoological Society for 1877 (p. 81), with a few additions collected by the U. S. Fish Commission Steamer Albatross, and published by the U. S. National Museum in 1889.
| Carabidæ. Feronia calathoides. ,, insularis. ,, galapagoensis. Amblygnathus obscuricornis. Solenophorus galapagoensis. Notaphus galapagoensis. Dytiscidæ. Eunectes occidentalis. Acilius incisus. Copelatus galapagoensis. Palpicornes. Tropisternus lateralis. Philhydrus sp. Staphylinidæ. Creophilus villosus. Necrophaga. Acribis serrativentris. Phalacrus darwinii. Dermestes vulpinus. Malacoderms. Ablechrus darwinii. Corynetes rufipes. Bostrichus unciniatus. Tetrapriocerca sp. Lamellicornes. Copris lugubris. Oryctes galapagoensis. |
Elateridæ. Physorhinus galapagoensis Heteromera. Allecula n. s. Stomion helopoides. ,, lævigatum. Ammophorus obscurus. ,, cooksoni. ,, bifoveatus. Pedonœces galapagoensis. ,, pubescens. Phaleria manicata. Curculionidæ. Otiorhynchus cuneiformis. Anchonus galapagoensis. Longicornia. Mallodou sp. Eburia amabilis. Anthribidæ. Ormiscus variegatus. Phytophaga. Diabrotica limbata. Docema galapagoensis. Longitarsus lunatus. Securipalpes. Scymuns galapagoensis. |
[114] Mr. H. O. Forbes, who visited these islands in 1878, increased the number of wild plants to thirty-six, and these belonged to twenty-six natural orders.
[115] Juan Fernandez is a good example of a small island which, with time and favourable conditions, has acquired a tolerably rich and highly peculiar flora and fauna. It is situated in 34° S. Lat., 400 miles from the coast of Chile, and so far as facilities for the transport of living organisms are concerned is by no means in a favourable position, for the ocean-currents come from the south-west in a direction where there is no land but the Antarctic continent, and the prevalent winds are also westerly. No doubt, however, there are occasional storms, and there may have been intermediate islands, but its chief advantages are its antiquity, its varied surface, and its favourable soil and climate, offering many chances for the preservation and increase of whatever plants and animals have chanced to reach it. The island consists of basalt, greenstone, and other ancient rocks, and though only about twelve miles long its mountains are three thousand feet high. Enjoying a moist and temperate climate it is especially adapted to the growth of ferns, which are very abundant; and as the spores of these plants are as fine as dust, and very easily carried for enormous distances by winds, it is not surprising that there are nearly fifty species on the island, while the remote period when it first received its vegetation may be indicated by the fact that nearly half the species are quite peculiar; while of 102 species of flowering plants seventy are peculiar, and there are ten peculiar genera. The same general character pervades the fauna. For so small an island it is rich, containing four true land-birds, about fifty species of insects, and twenty of land-shells. Almost all these belong to South American genera, and a large proportion are South American species; but several of the insects, half the birds, and the whole of the land-shells are peculiar. This seems to indicate that the means of transmission were formerly greater than they are now, and that in the case of land-shells none have been introduced for so long a period that all have become modified into distinct forms, or have been preserved on the island while they have become extinct on the continent. For a detailed examination of the causes which have led to the modification of the humming birds of Juan Fernandez see the chapter on Humming Birds in the author's Natural Selection and Tropical Nature, p. 324; while a general account of the fauna of the island is given in his Geographical Distribution of Animals, Vol. II. p. 49.
[116] No additions appear to have been made to this flora down to 1885, when Mr. Hemsley published his Report on the Present State of our Knowledge of Insular Floras.
[117] Journal of the Linnean Society, Vol. XIII., "Botany," p. 556.
[118] Geographical Distribution of Animals, Vol. II. p. 81.
[119] St. Helena: a Physical, Historical, and Topographical Description of the Island, &c. By John Charles Melliss, F.G.S., &c. London: 1875.
[120] Mr. Marsh in his interesting work entitled The Earth as Modified by Human Action (p. 51), thus remarks on the effect of browsing quadrupeds in destroying and checking woody vegetation.—"I am convinced that forests would soon cover many parts of the Arabian and African deserts if man and domestic animals, especially the goat and the camel, were banished from them. The hard palate and tongue, and strong teeth and jaws of this latter quadruped enable him to break off and masticate tough and thorny branches as large as the finger. He is particularly fond of the smaller twigs, leaves, and seed-pods of the Sont and other acacias, which, like the American robinia, thrive well on dry and sandy soils, and he spares no tree the branches of which are within his reach, except, if I remember right, the tamarisk that produces manna. Young trees sprout plentifully around the springs and along the winter water-courses of the desert, and these are just the halting stations of the caravans and their routes of travel. In the shade of these trees annual grasses and perennial shrubs shoot up, but are mown down by the hungry cattle of the Bedouin as fast as they grow. A few years of undisturbed vegetation would suffice to cover such points with groves, and these would gradually extend themselves over soils where now scarcely any green thing but the bitter colocynth and the poisonous foxglove is ever seen."
[121] Coleoptera Sanctæ Helenæ, 1877; Testacea Atlantica, 1878.
[122] On Petermann's map of Africa, in Stieler's Hand-Atlas (1879), the Island of Ascension is shown as seated on a much larger and shallower submarine bank than St. Helena. The 1,000 fathom line round Ascension encloses an oval space 170 miles long by 70 wide, and even the 300 fathom line, one over 60 miles long; and it is therefore probable that a much larger island once occupied this site. Now Ascension is nearly equidistant between St. Helena and Liberia, and such an island might have served as an intermediate station through which many of the immigrants to St. Helena passed. As the distances are hardly greater than in the case of the Azores, this removes whatever difficulty may have been felt of the possibility of any organisms reaching so remote an island. The present island of Ascension is probably only the summit of a huge volcanic mass, and any remnant of the original fauna and flora it might have preserved may have been destroyed by great volcanic eruptions. Mr. Darwin collected some masses of tufa which were found to be mainly organic, containing, besides remains of fresh-water infusoria, the siliceous tissue of plants! In the light of the great extent of the submarine bank on which the island stands, Mr. Darwin's remark, that—"we may feel sure, that at some former epoch, the climate and productions of Ascension were very different from what they are now,"—has received a striking confirmation. (See Naturalist's Voyage Round the World, p. 495.)
[123] "Notes on the Classification, History, and Geographical Distribution of Compositæ."—Journal of the Linnean Society, Vol. XIII. p. 563 (1873).
[124] The Melhaniæ comprise the two finest timber trees of St. Helena, now almost extinct, the redwood and native ebony.
[125] Journal of the Linnean Society, 1873, p. 496. "On Diversity of Evolution under one set of External Conditions." Proceedings of the Zoological Society of London, 1873, p. 80. "On the Classification of the Achitinellidæ."
[126] "Memoirs on the Coleoptera of the Hawaiian Islands." By the Rev. T. Blackburn, B.A., and Dr. D. Sharp. Scientific Transactions of the Royal Dublin Society. Vol. III. Series II. 1885.
[127] See Hildebrand's Flora of the Hawaiian Islands, Introduction, p. xiv.
[128] Flora of the Hawaiian Islands, by W. Hildebrand, M.D., annotated and published after the author's death by W. F. Hildebrand, 1888.
[129] These are obtained from Hildebrand's Flora supplemented by Mr. Bentham's paper in the Journal of the Linnean Society.
[130] Among the curious features of the Hawaiian flora is the extraordinary development of what are usually herbaceous plants into shrubs or trees. Three species of Viola are shrubs from three to five feet high. A shrubby Silene is nearly as tall; and an allied endemic genus, Schiedea, has numerous shrubby species. Geranium arboreum is sometimes twelve feet high. The endemic Compositæ are mostly shrubs, while several are trees reaching twenty or thirty feet in height. The numerous Lobeliaceæ, all endemic, are mostly shrubs or trees, often resembling palms or yuccas in habit, and sometimes twenty-five or thirty feet high. The only native genus of Primulaceæ—Lysimachia—consists mainly of shrubs; and even a plantain has a woody stem sometimes six feet high.
[131] Geological Magazine, 1870, p. 155.
[132] Transactions of the Edinburgh Geological Society, Vol. I. p. 330.
[133] Quarterly Journal of Geological Society, 1850, p. 96.
[134] British Association Report, Dundee, 1867, p. 431.
[135] The list of names was furnished to me by Dr. Günther, and I have added the localities from the papers containing the original descriptions, and from Dr. Haughton's British Freshwater Fishes.
[136] See "The Virginia Colony of Helix nemoralis," T. D. A. Cockerell, in The Nautilus, Vol. III. No. 7, p. 73.
[137] I am indebted to Mr. Mitten for this curious fact.
[138] The following remarks by Dr. Richard Spruce, who has made a special study of mosses and especially of hepaticæ, are of interest. "From what precedes, I conclude that no existing agency is capable of transporting the germs of our hepatics of tropical type from the torrid zone to Britain, and I venture to suppose that their existence at Killarney dates from the remote period when the vegetation of the whole northern hemisphere partook of a tropical character. If I am challenged to account for their survival through the last glacial period, I reply that, granting even the existence of a universal ice-cap down to the latitude of 40° in America and 50° in Europe, it is not to be assumed that the whole extent, even of land, was perennially entombed 'in thrilling regions of thick-ribbed ice.' Towards the southern margin of the ice the climate was probably very similar to that of Greenland and the northern part of Norway at the present day. The summer sun would have great power, and on the borders of sheltered fjords the frozen snow would disappear completely, if only for a very short period, and I ask only for a month or two, not doubting the capacity of our hepatics to survive in a dormant state under the snow for at least ten months in the year. I have gathered mosses in the Pyrenees where the snow had barely left them on August 2nd; by September 25th they were re-covered with snow, and would not be again uncovered till the following year. The mosses of Killarney might even enjoy a longer summer than this; for the gulf-stream laves both sides of the south-western angle of Ireland, and its tepid waters would exert great melting power on the ice-bound coast, preventing at the same time any formation of ice in the sea itself." This passage is the conclusion of a very interesting discussion on the distribution of hepaticæ in a paper on "A New Hepatic from Killarney," in the Journal of Botany, vol. 25, (Feb. 1887), pp. 33-82, in which many curious facts are given as to the habits and distribution of these curious and beautiful little plants.
[139] While these pages are passing through the press I am informed by my friend Mr. W. H. Beeby that in the Shetland Isles, where he has been collecting for five summers, he has found several plants new to the British flora, and a few altogether undescribed. Among these latter is a very distinct species of Hieracium (H. Zetlandicum), which is quite unknown in Scandinavia, and is almost certainly peculiar to the British Islands. Here we have another proof that entirely new species are still to be discovered in the remoter portions of our country.
[140] In the first edition of this work the numbers were 400 and 340, showing the great increase of our knowledge during the last ten years, chiefly owing to the researches of Mr. A. H. Everett in Sarawak and Mr. John Whitehead in North Borneo and the great mountain Kini Balu.
[141] These are Allocotops, Chlorocharis, Androphilus, and Ptilopyga, among the Timeliidæ; Tricophoropsis and Oreoctistes among the Brachypodidæ; Chlamydochœra among the Campophagidæ.
[142] In a letter from Darwin he says:—"Hooker writes to me, 'Miguel has been telling me that the flora of Sumatra and Borneo are identical, and that of Java quite different.'"
[143] "On the Geology of Sumatra," by M. R. D. M. Verbeck. Geological Magazine, 1877.
[144] Pitta megarhynchus (Banca) allied to P. brachyurus (Borneo, Sumatra, Malacca); and Pitta bangkanus (Banca) allied to P. sordidus (Borneo and Sumatra).
[145] The following list of the mammalia of the Philippines and the Sulu Islands has been kindly furnished me by Mr. Everett.
| Quadrumana. 1. Macacus cynomolgus. 2. Tarsius spectrum. Carnivora. 3. Viverra tangalunga. 4. Paradoxurus philippinensis. Also in Palawan. 5. Felis bengalensis. In Negros Island. Ungulata. 6. Bubalus mindorensis. Peculiar species. 7. Cervus philippinus. Peculiar species. 8. ,, alfredi. Peculiar species. 9. ,, nigricans. Peculiar species. 10. ,, pseudaxis. Sulu only. Probably introduced. 11. Sus marchesi. Peculiar species. Rodentia. 12. Sciurus philippinensis. Peculiar species. 13. ,, cagos. Peculiar species. 14. ,, concinnus. Peculiar. Mindanao and Basilan. 15. Phlæomys cummingi. Peculiar genus. 16. Mus ephippium. 17. ,, everetti. Peculiar species. Insectivora. 18. Crocidura luzoniensis. Peculiar species. 19. ,, edwardsiana. Peculiar species. 20. Dendrogale sp. 21. Galeopithecus philippinensis. Peculiar species. | Chiroptera. 22. Pteropus leucopterus. 23. ,, edulis. 24. ,, hypomelanus. 25. ,, jubatus. 26. Xantharpyia amplexicaule. 27. Cynopterus marginatus. 28. ,, jagorii. Peculiar species. 29. Carponycteris australis. 30. Rhinolophus luctus. 31. ,, philippinensis. Peculiar species. 32. ,, rufus. Peculiar species. 33. Hipposideros diadema. 34. ,, pygmæus. Peculiar species. 35. ,, larvatus. 36. ,, obscurus. Peculiar species. 37. ,, coronatus. Peculiar species. 38. ,, bicolor. 39. Megaderma spasma. 40. Vesperugo pachypus. 41. ,, tenuis. 42. ,, abramus. 43. Nycticejus kuhlii. 44. Vespertilio macrotarsus. Peculiar species. 45. ,, capaccinii. 46. Harpiocephalus cyclotis. 47. Kerivoula hardwickii. 48. ,, pellucida. Peculiar species. 49. ,, jagorii. Peculiar species. 50. Miniopterus schreibersii. 51. ,, tristis. Peculiar species. 52. Emballonura monticola. 53. Taphyzous melanopogon. 54. Nyctinomus plicatus. |
[146] Extracted from Messrs. Blakiston and Pryer's Catalogue of Birds of Japan (Ibis, 1878, p. 209), with Mr. Seebohm's additions and corrections in his Birds of the Japanese Empire 1890. Accidental stragglers are not reckoned as British birds.
[147] Mr. Swinhoe died in October, 1877, at the early age of forty-two. His writings on natural history are chiefly scattered through the volumes of the Proceedings of the Zoological Society and The Ibis; the whole being summarised in his Catalogue of the Mammals of South China and Formosa (P. Z. S., 1870, p. 615), and his Catalogue of the Birds of China and its Islands (P. Z. S., 1871, p. 337).
[148] Captain Blakiston has shown that the northern island—Yezo—is much more temperate and less peculiar in its zoology than the central and southern islands. This is no doubt dependent chiefly on the considerable change of climate that occurs on passing the Tsu-garu strait.
[149] See Dr. J. E. Gray's "Revision of the Viverridæ," in Proc. Zool. Soc. 1864, p. 507.
[150] Some of the Bats of Madagascar and East Africa are said to have their nearest allies in Australia. (See Dobson in Nature, Vol. XXX. p. 575.)
[151] This view was, I believe, first advanced by Professor Huxley in his "Anniversary Address to the Geological Society," in 1870. He says:—"In fact the Miocene mammalian fauna of Europe and the Himalayan regions contain, associated together, the types which are at present separately located in the South African and Indian provinces of Arctogæa. Now there is every reason to believe, on other grounds, that both Hindostan south of the Ganges, and Africa south of the Sahara, were separated by a wide sea from Europe and North Asia during the Middle and Upper Eocene epochs. Hence it becomes highly probable that the well-known similarities, and no less remarkable differences, between the present faunæ of India and South Africa have arisen in some such fashion as the following: Some time during the Miocene epoch, the bottom of the nummulitic sea was upheaved and converted into dry land in the direction of a line extending from Abyssinia to the mouth of the Ganges. By this means the Dekkan on the one hand and South Africa on the other, became connected with the Miocene dry land and with one another. The Miocene mammals spread gradually over this intermediate dry land; and if the condition of its eastern and western ends offered as wide contrasts as the valleys of the Ganges and Arabia do now, many forms which made their way into Africa must have been different from those which reached the Dekkan, while others might pass into both these sub-provinces."
This question is fully discussed in my Geographical Distribution of Animals (Vol. I., p. 285), where I expressed views somewhat different from those of Professor Huxley, and made some slight errors which are corrected in the present work. As I did not then refer to Professor Huxley's prior statement of the theory of Miocene immigration into Africa (which I had read but the reference to which I could not recall) I am happy to give his views here.
[152] The total number of Madagascar birds is 238, of which 129 are absolutely peculiar to the island, as are thirty-five of the genera. All the peculiar birds but two are land birds. These are the numbers given in M. Grandidier's great work on Madagascar.
[153] The Ibis, 1877, p. 334.
[154] In a paper read before the Geological Society in 1874, Mr. H. F. Blanford, from the similarity of the fossil plants and reptiles, supposed that India and South Africa had been connected by a continent, "and remained so connected with some short intervals from the Permian up to the end of the Miocene period," and Mr. Woodward expressed his satisfaction with "this further evidence derived from the fossil flora of the Mesozoic series of India in corroboration of the former existence of an old submerged continent—Lemuria."
Those who have read the preceding chapters of the present work will not need to have pointed out to them how utterly inconclusive is the fragmentary evidence derived from such remote periods (even if there were no evidence on the other side) as indicating geographical changes. The notion that a similarity in the productions of widely separated continents at any past epoch is only to be explained by the existence of a direct land-connection, is entirely opposed to all that we know of the wide and varying distribution of all types at different periods, as well as to the great powers of dispersal over moderate widths of ocean possessed by all animals except mammalia. It is no less opposed to what is now known of the general permanency of the great continental and oceanic areas; while in this particular case it is totally inconsistent (as has been shown above) with the actual facts of the distribution of animals.
[155] Geographical Distribution of Animals, Vol. I., pp. 272-292.
[156] The term "Mascarene" is used here in an extended sense, to include all the islands near Madagascar which resemble it in their animal and vegetable productions.
[157] For the birds of the Comoro Islands see Proc. Zool. Soc., 1877, p. 295, and 1879, p. 673.
[158] The following is a list of these peculiar birds. (See the Ibis, for 1867, p. 359; and 1879, p. 97.)
| Passeres. Ellisia seychelensis. Copsychus seychellarum. Hypsipetes crassirostris. Tchitrea corvina. Nectarinia dussumieri. Zosterops modesta. " semiflava. Foudia seychellarum. | Psittaci. Coracopsis barklyi. Palæornis wardi. Columbæ. Alectorænas pulcherrimus. Turtur rostratus. Accipitres. Tinnunculus gracilis. |
[159] Specimens are recorded from West Africa in the Proceedings of the Academy of Natural Science, Philadelphia, 1857, p. 72, while specimens in the Paris Museum were brought by D'Orbigny from S. America. Dr. Wright's specimens from the Seychelles have, as he informs me, been determined to be the same species by Dr. Peters of Berlin.
[160] "Additional Notes on the Land-shells of the Seychelles Islands." By Geoffrey Nevill, C.M.Z.S. Proc. Zool. Soc. 1869, p. 61.
[161] In Maillard's Notes sur l'Isle de Réunion, a considerable number of mammalia are given as "wild," such as Lemur mongoz and Centetes setosus, both Madagascar species, with such undoubtedly introduced animals as a wild cat, a hare, and several rats and mice. He also gives two species of frogs, seven lizards, and two snakes. The latter are both Indian species and certainly imported, as are most probably the frogs. Legouat, who resided some years in the island nearly two centuries ago, and who was a closer observer of nature, mentions numerous birds, large bats, land-tortoises, and lizards, but no other reptiles or venomous animals except scorpions. We may be pretty sure, therefore, that the land-mammalia, snakes, and frogs, now found wild, have all been introduced. Of lizards, on the other hand, there are several species, some peculiar to the island, others common to Africa and the other Mascarene Islands. The following list by Prof. Dumeril is given in Maillard's work:—
| Platydactylus cepedianus. " ocellatus. Hemidactylus peronii. " mutilatus. | Hemidactylus frenatus. Gongylus bojerii. Ablepharus peronii. |
Four species of chameleon are now recorded from Bourbon and one from Mauritius (J. Reay Greene, M.D., in Pop. Science Rev. April, 1880), but as they are not mentioned by the old writers, it is pretty certain that these creatures are recent introductions, and this is the more probable as they are favourite domestic pets.
Darwin informed me that in a work entitled Voyage à l'Isle de France, par un Officier du Roi, published in 1770, it is stated that a fresh-water fish had been introduced from Batavia and had multiplied. The writer also says (p. 170): "On a essayé, mais sans succcès, d'y transporter des grenouilles qui mangent les œufs que les moustigues deposent sur les eaux stagnantes." It thus appears that there were then no frogs on the island.
[162] That the dodo is really an abortion from a more perfect type, and not a direct development from some lower form of wingless bird, is shown by its possessing a keeled sternum, though the keel is exceedingly reduced, being only three-quarters of an inch deep in a length of seven inches. The most terrestrial pigeon—the Didunculus of the Samoan Islands, has a far deeper and better developed keel, showing that in the case of the dodo the degradation has been extreme. We have also analogous examples in other extinct birds of the same group of islands, such as the flightless Rails—Aphanapteryx of Mauritius and Erythromachus of Rodriguez, as well as the large parrot—Lophopsittacus of Mauritius, and the Night Heron, Nycticorax megacephala of Rodriguez, the last two birds probably having been able to fly a little. The commencement of the same process is to be seen in the peculiar dove of the Seychelles, Turtur rostratus, which, as Mr. Edward Newton has shown, has much shorter wings than its close ally, T. picturatus, of Madagascar. For a full and interesting account of these and other recently extinct birds see Professor Newton's article on "Fossil Birds" in the Encyclopædia Britannica, ninth edition, vol. iii., p. 732; and that on "The Extinct Birds of Rodriguez," by Dr. A. Günther and Mr. E. Newton, in the Royal Society's volume on the Transit of Venus Expedition.
[163] See Ibis, 1877, p. 334.
[164] A common Indian and Malayan toad (Bufo melanostictus) has been introduced into Mauritius and also some European toads, as I am informed by Dr. Günther.
[165] This brief account of the Madagascar flora has been taken from a very interesting paper by the Rev. Richard Baron, F.L.S., F.G.S., in the Journal of the Linnean Society, Vol. XXV., p. 246; where much information is given on the distribution of the flora within the island.
[166] It may be interesting to botanists and to students of geographical distribution to give here an enumeration of the endemic genera of the Flora of the Mauritius and the Seychelles, as they are nowhere separately tabulated in that work.
| Aphloia (Bixaceæ) | 1 sp., a shrub, Maur., Rod., Sey., also Madagascar. |
| Medusagyne (Ternströmiaceæ) | 1 sp., a shrub, Seychelles. |
| Astiria (Sterculiaceæ) | 1 sp., a shrub, Mauritius. |
| Quivisia (Meliaceæ) | 3 sp., shrubs, Mauritius (2 sp.), Rodriguez (1 sp.), also Bourbon. |
| Cossignya (Sapindaceæ) | 1 sp., a shrub, Mauritius, also Bourbon. |
| Hornea ,, | 1 sp., a shrub, Mauritius. |
| Stadtmannia ,, | 1 sp., a shrub, Mauritius. |
| Doratoxylon ,, | 1 sp., a shrub, Mauritius and Bourbon. |
| Gagnebina (Leguminosæ) | 1 sp., a shrub, Mauritius, also Madagascar. |
| Roussea (Saxifragaceæ) | 1 sp., a climbing shrub, Mauritius and Bourbon. |
| Tetrataxis (Lythraceæ) | 1 sp., a shrub, Mauritius. |
| Psiloxylon ,, | 1 sp., a shrub, Mauritius and Bourbon. |
| Mathurina (Turneraceæ) | 1 sp., a shrub, Rodriguez. |
| Fœtidia (Myrtaceæ) | 1 sp., a tree, Mauritius. |
| Danais (Rubiaceæ) | 4 sp., climbing shrubs, Maur. (1 sp.), Rodr. (1 sp.), also Bourbon and Madagascar. |
| Fernelia (Rubiaceæ) | 1 sp., a shrub, Mauritius and Rodriguez. |
| Pyrostria ,, | 6 sp., shrubs, Mauritius (3 sp.), also Bourbon and Madagascar. |
| Scyphochlamys (Rubiaceæ) | 1 sp., a shrub, Rodriguez. |
| Myonima ,, | 3 sp., shrubs, Mauritius, also Bourbon. |
| Cylindrocline (Compositæ) | 1 sp., a shrub, Mauritius. |
| Monarrhenus ,, | 2 sp., shrubs, Mauritius, also Bourbon and Madagascar. |
| Faujasia (Compositæ) | 3 sp., shrubs, Mauritius, also Bourbon and Madagascar. |
| Heterochænia (Campanulaceæ) | 1 sp., a shrub, Mauritius, also Bourbon. |
| Tanulepis (Asclepiadaceæ) | 1 sp., a climber, Rodriguez. |
| Decanema ,, | 1 sp., a climber, Mauritius, also Madagascar. |
| Nicodemia (Loganiaceæ) | 2 sp., shrubs, Mauritius (1 sp.), also Comoro Islands and Madagascar. |
| Bryodes (Scrophulariaceæ) | 1 sp., herb, Mauritius. |
| Radamæa ,, | 2 sp., herb, Seychelles (1 sp.), and Madagascar. |
| Colea (Bignoniaceæ) | 10 sp., Mauritius (1 sp.), Seychelles (1 sp.), also Bourbon and Madagascar. (Shrubs, trees, or climbers.) |
| Obetia (Urticaceæ) | 2 sp., shrubs, Mauritius, Seychelles, and Madagascar. |
| Bosquiea (Moreæ) | 3 sp., trees, Seychelles (1 sp.), also Madagascar. |
| Monimia (Monimiaceæ) | 3 sp., trees, Mauritius (2 sp.), also Bourbon. |
| Cynorchis (Orchideæ) | 3 sp., herb, ter., Mauritius. |
| Amphorchis ,, | 1 sp., herb, ter., Mauritius, also Bourbon. |
| Arnottia ,, | 2 sp., herb, ter., Mauritius, also Bourbon. |
| Aplostellis ,, | 1 sp., herb, ter., Mauritius. |
| Cryptopus ,, | 1 sp., herb, Epiphyte, Mauritius, also Bourbon and Madagascar. |
| Lomatophyllum (Liliaceæ) | 3 sp., shrubs (succulent), Mauritius, also Bourbon. |
| Lodoicea (Palmæ) | 1 sp., tree, Seychelles. |
| Latania ,, | 3 sp., trees, Mauritius (2 sp.), Rodriguez, also Bourbon. |
| Hyophorbe ,, | 3 sp., trees, Mauritius (2 sp.), Rodriguez, also Bourbon. |
| Dictyosperma ,, | 1 sp., tree, Mauritius, Rodriguez, also Bourbon. |
| Acanthophænix ,, | 2 sp., trees, Mauritius, also Bourbon. |
| Deckenia ,, | 1 sp., tree, Seychelles. |
| Nephrosperma ,, | 1 sp., tree, Seychelles. |
| Roscheria ,, | 1 sp., tree, Seychelles. |
| Verschaffeltia ,, | 1 sp., tree, Seychelles. |
| Stevensonia ,, | 1 sp., tree, Seychelles. |
| Ochropteris (Filices) | 1 sp., herb, Mauritius, also Bourbon and Madagascar. |
Among the curious features in this list are the great number of endemic shrubs in Mauritius, and the remarkable assemblage of five endemic genera of palms in the Seychelles Islands. We may also notice that one palm (Latania loddigesii) is confined to Round Island and two other adjacent islets offering a singular analogy to the peculiar snake also found there.
| Families of Malayan Birds not found in islands East of Celebes. | Families of Moluccan Birds not found in islands West of Celebes. |
| Troglodytidæ. Sittidæ. Paridæ. Liotrichidæ. Phyllornithidæ. Eurylæmidæ. Picidæ. Indicatoridæ. Megalænidæ. Trogonidæ. Phasianidæ. |
Paradiseidæ. Meliphagidæ. Cacatuidæ. Platycercidæ. Trichoglossidæ. Nestoridæ. |
[168] For outline figures of the chief types of these butterflies, see my Malay Archipelago, Vol. I. p. 441, or p. 216 of the tenth edition.
[169] Dobson on the Classification of Chiroptera (Ann. and Mag. of Nat. Hist. Nov. 1875).
[170] See Buller, "On the New Zealand Rat," Trans. of the N. Z. Institute (1870), Vol. III. p. 1, and Vol. IX. p. 348; and Hutton, "On the Geographical Relations of the New Zealand Fauna," Trans. N. Z. Instit. 1872, p. 229.
[171] Hochstetter's New Zealand, p. 161, note.
[172] The animal described by Captain Cook as having been seen at Pickersgill Harbour in Dusky Bay (Cook's 2nd Voyage, Vol. I. p. 98) may have been the same creature. He says, "A four-footed animal was seen by three or four of our people, but as no two gave the same description of it, I cannot say what kind it is. All, however, agreed that it was about the size of a cat, with short legs, and of a mouse colour. One of the seamen, and he who had the best view of it, said it had a bushy tail, and was the most like a jackal of any animal he knew." It is suggestive that, so far as the points on which "all agreed"—the size and the dark colour—this description would answer well to the animal so recently seen, while the "short legs" correspond to the otter-like tracks, and the thick tail of an otter-like animal may well have appeared "bushy" when the fur was dry. It has been suggested that it was only one of the native dogs; but as none of those who saw it took it for a dog, and the points on which they all agreed are not dog-like, we can hardly accept this explanation; while the actual existence of an unknown animal in New Zealand of corresponding size and colour is confirmed by this account of a similar animal having been seen about a century ago.
[173] Owen, "On the Genus Dinornis," Trans. Zool. Soc. Vol. X. p. 184. Mivart, "On the Axial Skeleton of the Struthionidæ," Trans. Zool. Soc. Vol. X. p. 51.
[174] The recent existence of the Moa and its having been exterminated by the Maoris appears to be at length set at rest by the statement of Mr. John White, a gentleman who has been collecting materials for a history of the natives for thirty-five years, who has been initiated by their priests into all their mysteries, and is said to "know more about the history, habits, and customs of the Maoris than they do themselves." His information on this subject was obtained from old natives long before the controversy on the subject arose. He says that the histories and songs of the Maoris abound in allusions to the Moa, and that they were able to give full accounts of "its habits, food, the season of the year it was killed, its appearance, strength, and all the numerous ceremonies which were enacted by the natives before they began the hunt, the mode of hunting, how cut up, how cooked, and what wood was used in the cooking, with an account of its nest, and how the nest was made, where it usually lived, &c." Two pages are occupied by these details, but they are only given from memory, and Mr. White promises a full account from his MSS. Many of the details given correspond with facts ascertained from the discovery of native cooking places with Moas' bones; and it seems quite incredible that such an elaborate and detailed account should be all invention. (See Transactions of the New Zealand Institute, Vol. VIII. p. 79.)
[175] See fig. in Trans. of N. Z. Institute, Vol. III., plate 12b. fig. 2.
[176] Geographical Distribution of Animals, Vol. I., p. 450.
[177] In my Geographical Distribution of Animals (I. p. 541) I have given two peculiar Australian genera (Orthonyx and Tribonyx) as occurring in New Zealand. But the former has been found in New Guinea, while the New Zealand bird is considered to form a distinct genus, Clitonyx; and the latter inhabits Tasmania, and was recorded from New Zealand through an error. (See Ibis, 1873, p. 427.)
[178] The peculiar genera of Australian lizards according to Boulenger's British Museum Catalogue, are as follows:—Family Geckonidæ: Nephrurus, Rhynchœdura, Heteronota, Diplodactylus, Œdura. Family Pygopodidæ (peculiar): Pygopus, Cryptodelma, Delma, Pletholax, Aprasia. Family Agamidæ: Chelosania, Amphibolurus, Tympanocryptis, Diporophora, Chlamydosaurus, Moloch, Oreodeira. Family Scincidæ: Egerina, Trachysaurus, Hemisphænodon. Family doubtful: Ophiopsiseps.
[179] These figures are taken from Mr. G. M. Thomson's address "On the Origin of the New Zealand Flora," Trans. N. Z. Institute, XIV. (1881), being the latest that I can obtain. They differ somewhat from those given in the first edition, but not so as to affect the conclusions drawn from them.
[180] This accords with the general scarcity of Leguminosæ in Oceanic Islands, due probably to their usually dry and heavy seeds, not adapted to any of the forms of aërial transmission; and it would indicate either that New Zealand was never absolutely united with Australia, or that the union was at a very remote period when Leguminosæ were either not differentiated or comparatively rare.
[181] Sir Joseph Hooker informs me that the number of tropical Australian plants discovered within the last twenty years is very great, and that the statement as above made may have to be modified. Looking, however, at the enormous disproportion of the figures given in the "Introductory Essay" in 1859 (2,200 tropical to 5,800 temperate species) it seems hardly possible that a great difference should not still exist, at all events as regards species. In Baron von Müeller's latest summary of the Australian Flora (Second Systematic Census of Australian Plants, 1889), he gives the total species at 8,839, of which 3,560 occur in West Australia, and 3,251 in New South Wales. On counting the species common to these two colonies in fifty pages of the Census taken at random, I find them to be about one-tenth of the total species in both. This would give the number of distinct species in these areas as about 6,130. Adding to these the species peculiar to Victoria and South Australia, we shall have a flora of near 6,500 in the temperate parts of Australia. It is true that West Australia extends far into the tropics, but an overwhelming majority of the species have been discovered in the south-western portion of the colony, while the species that may be exclusively tropical will be more than balanced by those of temperate Queensland, which have not been taken account of, as that colony is half temperate and half tropical. It thus appears probable that full three fourths of the species of Australian plants occur in the temperate regions, and are mainly characteristic of it. Sir Joseph Hooker also doubts the generally greater richness of tropical over temperate floras which I have taken as almost an axiom. He says: "Taking similar areas to Australia in the Western World, e.g., tropical Africa north of 20° S. Lat. as against temperate Africa and Europe up to 47°—I suspect that the latter would present more genera and species than the former." This, however, appears to me to be hardly a case in point, because Europe is a distinct continent from Africa and has had a very different past history, and it is not a fair comparison to take the tropical area in one continent while the temperate is made up of widely separated areas in two continents. A closer parallel may perhaps be found in equal areas of Brazil and south temperate America, or of Mexico and the Southern United States, in both of which cases I suppose there can be little doubt that the tropical areas are far the richest. Temperate South Africa is, no doubt, always quoted as richer than an equal area of tropical Africa or perhaps than any part of the world of equal extent, but this is admitted to be an exceptional case.
[182] Sir Joseph Hooker thinks that later discoveries in the Australian Alps and other parts of East and South Australia may have greatly modified or perhaps reversed the above estimate, and the figures given in the preceding note indicate that this is so. But still, the small area of South-west Australia will be, proportionally, far the richer of the two. It is much to be desired that the enormous mass of facts contained in Mr. Bentham's Flora Australiensis and Baron von Müeller's Census should be tabulated and compared by some competent botanist, so as to exhibit the various relations of its wonderful vegetation in the same manner as was done by Sir Joseph Hooker with the materials available twenty-one years ago.
[183] From an examination of the fossil corals of the South-west of Victoria, Professor P. M. Duncan concludes—"that, at the time of the formation of these deposits the central area of Australia was occupied by sea, having open water to the north, with reefs in the neighbourhood of Java." The age of these fossils is not known, but as almost all are extinct species, and some are almost identical with European Pliocene and Miocene species, they are supposed to belong to a corresponding period. (Journal of Geol. Soc., 1870.)
[184] "On the Origin of the Fauna and Flora of New Zealand," by Captain F. W. Hutton, in Annals and Mag. of Nat. Hist. Fifth series, p. 427 (June, 1884).
[185] To these must now be added the genera Sequoia, Myrica, Aralia, and Acer, described by Baron von Ettingshausen. (Trans. N.Z. Institute, xix., p. 449.)
[186] The large collection of fossil plants from the Tertiary beds of New Zealand which have been recently described by Baron von Ettingshausen (Trans. N. Z. Inst., vol. xxiii., pp. 237-310), prove that a change in the vegetation has occurred similar to that which has taken place in Eastern Australia, and that the plants of the two countries once resembled each other more than they do now. We have, first, a series of groups now living in Australia, but which have become extinct in New Zealand, as Cassia, Dalbergia, Eucalyptus, Diospyros, Dryandra, Casuarina, and Ficus; and also such northern genera as Acer, Planera, Ulmus, Quercus, Alnus, Myrica, and Sequoia. All these latter, except Ulmus and Planera, have been found also in the Eastern-Australian Tertiaries, and we may therefore consider that at this period the northern temperate element in both floras was identical. If this flora entered both countries from the south, and was really Antarctic, its extinction in New Zealand may have been due to the submergence of the country to the south, and its elevation and extension towards the tropics, admitting of the incursion of the large number of Polynesian and tropical Australian types now found there; while the Australian portion of the same flora may have succumbed at a somewhat later period, when the elevation of the Cretaceous and Tertiary sea united it with Western Australia, and allowed the rich typical Australian flora to overrun the country. Of course we are assuming that the identification of these genera is for the most part correct, though almost entirely founded on leaves only. Fuller knowledge, both of the extinct flora itself and of the geological age of the several deposits, is requisite before any trustworthy explanation of the phenomena can be arrived at.
[187] The following are the tropical genera common to New Zealand and Australia:—