Popular Science Monthly/Volume 33/September 1888/A Fossil Continent
|←Heliotropism: The Turning Motions of Plants|| Popular Science Monthly Volume 33 September 1888 (1888)
A Fossil Continent
|Sketch of Carl Friedrich Gauss→|
IF an intelligent Australian colonist were suddenly to be translated backward from Collins Street, Melbourne, into the flourishing woods of the secondary geological period — say about the precise moment of time when the English chalk downs were slowly accumulating, speck by speck, on the silent floor of some long-forgotten Mediterranean — the intelligent colonist would look around him with a sweet smile of cheerful recognition, and say to himself in some surprise, "Why, this is just like Australia." The animals, the trees, the plants, the insects, would all more or less vividly remind him of those he had left behind him in his happy home of the southern seas and the nineteenth century. The sun would have moved back on the dial of ages for a few million summers or so, indefinitely (in geology we refuse to be bound by dates), and would have landed him at last, to his immense astonishment, pretty much at the exact point whence he first started.
In other words, with a few needful qualifications, to be made hereafter, Australia is, so to speak, a fossil continent, a country still in its secondary age, a surviving fragment of the primitive world of the chalk period or earlier ages. Isolated from all the remainder of the earth about the beginning of the Tertiary epoch, A FOSSIL CONTINENT. 683
long before the mammoth and the mastodon had yet dreamed of appearing upon the stage of existence, long before the first shadowy ancestor of the horse had turned tail on Nature's rough draught of the still undeveloped and unspecialized lion, long be- fore the extinct dinotheriums and gigantic Irish elks and colossal giraffes of late Tertiary times had even begun to run their race on the broad plains of Europe and America, the Australian conti- nent found itself at an early period of its development cut off en- tirely from all social intercourse with the remainder of our planet, and turned upon itself, like the German philosopher, to evolve its own plants and animals out of its own inner consciousness. The natural consequence was, that progress in Australia has been ab- surdly slow, and that the country as a whole has fallen most wo- fully behind the times in all matters pertaining to the existence of life upon its surface. Everybody knows that Australia as a whole is a very peculiar and original continent ; its peculiarity, however, consists, at bottom, for the most part in the fact that it still remains at very nearly the same early point of development which Europe had attained a couple of million years ago or there- about. "Advance, Australia," says the national motto; and, in- deed, it is quite time nowadays that Australia should advance ; for, so far, she has been left out of the running for some four mundane ages or so at a rough computation.
Example, says the wisdom of our ancestors, is better than pre- cept ; so perhaps, if I take a single example to start with, I shall make the principle I wish to illustrate a trifle clearer to the Euro- pean comprehension. In Australia, when Cook or Van Diemen first visited it, there were no horses, cows, or sheep ; no rabbits, weasels, or cats ; no indigenous quadrupeds of any sort except the pouched mammals or marsupials, familiarly typified to every one of us by the mamma kangaroo in Regent's Park, who carries the baby kangaroos about with her, neatly deposited in the sac or pouch which Nature has provided for them instead of a cradle. To this rough generalization, to be sure, two special exceptions must needs be made ; namely, the noble Australian black-fellow himself, and the dingo or wild dog, whose ancestors no doubt came to the country in the same ship with him, as the brown rat came to England with George I of blessed memory. But of these two solitary representatives of the later and higher Asiatic fauna " more anon " ; for the present we may regard it as approximately true that aboriginal and unsophisticated Australia in the lump was wholly given over, on its first discovery, to kangaroos, pha- langers, dasyures, wombats, and other quaint marsupial animals, with names as strange and clumsy as their forms.
Now, who and what are the marsupials as a family, viewed in the dry light of modern science ? Well, they are simply one of
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the very oldest mammalian families, and therefore, I need hardly say, in the leveling and topsy-turvy view of evolutionary biology, the least entitled to consideration or respect from rational observ- ers. For of course in the kingdom of science the last shall be first, and the first last ; it is the oldest families that are accounted the worst, while the best families mean always the newest. Now, the earliest mammals to appear on earth were creatures of distinctly marsupial type. As long ago as the time when the red marl of Devonshire and the blue lias of Lyme Regis were laid down on the bed of the muddy sea that once covered the surface of Dorset and the English Channel, a little creature like the kangaroo rats of Southern Australia lived among the plains of what is now the south of England. In the ages succeeding the deposition of the red marl, Europe seems to have been broken up into an archi- pelago of coral reefs and atolls ; and the islands of this ancient oolitic ocean were tenanted by numbers of tiny ancestral marsu- pials, some of which approached in appearance the pouched ant- eaters of Western Australia, while others resembled rather the phalangers and wombats, or turned into excellent imitation car- nivores, like our modern friend the Tasmanian devil. Up . to the end of the time when the chalk deposits of Surrey, Kent, and Sus- sex were laid down, indeed, there is no evidence of the existence anywhere in the world of any mammals differing in type from those which now inhabit Australia. In other words, so far as re- gards mammalian life, the whole of the world had then already reached pretty nearly the same point of evolution that poor Aus- tralia still sticks at.
About the beginning of the Tertiary period, however, just after the chalk was all deposited, and just before the comparatively modern clays and sandstones of the London basin began to be laid down, an arm of the sea broke up the connection which once sub- sisted between Australia and the rest of the world, probably by a land-bridge, via Java, Sumatra, the Malay Peninsula, and Asia generally. " But how do you know," asks the candid inquirer, " that such a connection ever existed at all ? " Simply thus, most laudable investigator — because there are large land mammals in Australia. Now, large land mammals do not swim across a broad ocean. There are none in New Zealand, none in the Azores, none in Fiji, none in Tahiti, none in Madeira, none in Teneriffe — none, in short, in any oceanic island which never at any time formed part of a great continent. How could there be, indeed ? The mammals must necessarily have got there from somewhere ; and whenever we find islands like Britain, or Japan, or Newfoundland, or Sicily, possessing large and abundant indigenous quadrupeds of the same general type as adjacent continents, we see at once that the island must formerly have been a mere peninsula, like
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Italy or Nova Scotia at the present day. The very fact that Aus- tralia incloses a large group of biggish quadrupeds, whose con- geners once inhabited Europe and America, suffices in itself to prove beyond question that uninterrupted land communication must once have existed between Australia and those distant con- tinents.
In fact, to this day a belt of very deep sea, known as Wallace's Line, from the great naturalist who first pointed out its far-reach- ing zoological importance, separates what is called by science " the Australian province " on the southwest from " the Indo-Malayan province " to the north and east of it. This belt of deep sea di- vides off sharply the plants and animals of the Australian type from those of the common Indian and Burmese pattern. South of Wallace's line we now find several islands, big and small, in- cluding New Guinea, Australia, Tasmania, the Moluccas, Celebes, Timor, Amboyna, and Banda. All these lands, whose precise geo- graphical position on the map must of course be readily remem- bered, in this age of school-boards and universal examination, by every pupil-teacher and every Girton girl, are now divided by minor straits of much shallower water ; but they all stand on a great submarine bank, and obviously formed at one time parts of the same wide Australian continent, because the animals of Aus- tralian type are still found in every one of them. No Indian or Malayan animal, however, of the larger sort (other than birds) is to be discovered anywhere south of Wallace's Line. That nar- row belt of deep sea, in short, forms an ocean barrier which has subsisted there without alteration ever since the end of the Sec- ondary period. From that time to this, as the evidence shows us, there has never been any direct land communication between Australia and any part of the outer world beyond that narrow line of division.
Some years ago, in fact, a clever hoax took the world by sur- prise for a moment, under the audacious title of " Captain Law- son's Adventures in New Guinea." The gallant captain, or his unknown creator in some London lodging, pretended to have ex- plored the Papuan jungles, and there to have met with marvelous escapes from terrible beasts of the common tropical Asiatic pat- tern — rhinoceroses, tigers, monkeys, and leopards. Everybody believed the new Munchausen at first, except the zoologists. Those canny folk saw through the wicked hoax on the very first blush of it. If there were rhinoceroses in Papua, they must have got there by an overland route. If there had ever been a land- connection between New Guinea and the Malay region, then, since Australian animals range into New Guinea, Malayan animals would have ranged into Australia, and we should find Victoria and New South Wales at the present day peopled by tapirs, orang-
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ou tangs, wild boars, deer, elephants, and squirrels, like those which now people Borneo, instead of, or side by side with, the kanga- roos, wombats, and other marsupials, which, as we know, actually form the sole indigenous mammalian population of Greater Brit- ain beneath the Southern Cross. Of course, in the end, the mys- terious and tremendous Captain Lawson proved to be a myth, an airy nothing, upon whom imagination had bestowed a local habi- tation (in New Guinea) and a name (not to be found in the army list). Wallace's Line was saved from reproach, and the intrusive rhinoceros was banished without appeal from the soil of Papua.
After the deep belt of open sea was thus established between the bigger Australian continent and the Malayan region, how- ever, the mammals of the great mainlands continued to develop on their own account, in accordance with the strictest Darwinian principles, among the wider plains of their own habitats. The competition there was fiercer and more general ; the struggle for life was bloodier and more arduous. Hence, while the old-fash- ioned marsupials continued to survive and to evolve slowly along their own lines in their own restricted southern world, their col- lateral descendants in Europe, and Asia, and America, or else- where, went on progressing into far higher, stronger, and better adapted forms — the great central mammalian fauna. In place of the petty phalangers and pouched ant-eaters of the oolitic period, our tertiary strata in the larger continents show us a rapid and extraordinary development of the mammalian race into monstrous creatures, some of them now quite extinct, and some still holding their own undisturbed in India, Africa, and the American prairies. The paleotherium and the dinoceras, the mastodon and the mam- moth, the huge giraffes and antelopes of sunnier times, succeed to the ancestral kangaroos and wombats of the Secondary strata. Slowly the horses grow more horse-like, the shadowy camel begins to camelize himself, the buffaloes acquire the rudiments of horns, the deer branch out by tentative steps into still more complicated and more complicated antlers. Side by side with this wonderful outgrowth of the mammalian type, in the first plasticity of its vig- orous youth, the older marsupials die away one by one in the ge- ological record before the faces of their more successful competi- tors ; the new carnivores devour them wholesale, the new rumi- nants eat up their pastures, the new rodents outwit them in the modernized forests. At last the pouched creatures all disappear utterly from all the world, save only Australia, with the solitary exception of a single advanced marsupial family, the familiar opossum of plantation melodies. And the history of the opossum himself is so very singular that it almost deserves to receive the polite attention of a separate paragraph for its own proper eluci- dation.
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For the opossums form the only memibers of the m.arsupial class now living outside Australia; and yet, what is at least equally remarkable, none of the opossums are found per contra in Australia itself. They are, in fact, the highest and best prod- uct of the old dying marsupial stock, specially evolved in the great continents through the fierce competition of the higher mammals then being developed on every side of them. Therefore, being later in point of time than the separation, they could no more get over to Australia than the elephants and tigers and rhinoceroses could. They are the last bid for life of the marsupial race in its hopeless struggle against its more developed mammalian cousins. In Europe and Asia the opossums lived on lustily, in spite of com- petition, during the whole of the Eocene period, side by side with hog-like creatures not yet perfectly piggish, with nondescript ani- mals, half horse, half tapir, and with hornless forms of deer and antelopes, unprovided, so far, with the first rudiment of budding antlers. But in the succeeding age they seem to disappear from the Eastern continent, though in the Western, thanks to their hand- like feet, opposable thumb, and tree-haunting life, they still drag out a precarious existence in many forms from Virginia to Chili, and from Brazil to California. It is worth while to notice, too, that whereas the kangaroos and other Australian marsupials are proverbially the very stupidest of mammals, the opossums, on the contrary, are well known to those accurate observers of animal psychology, the plantation negroes, to be the very cleverest, cun- ningest, and slyest of American quadrupeds. In the fierce strug- gle for life of the crowded American lowlands, the opossum was absolutely forced to acquire a certain amount of Yankee smart- ness, or else to be improved off the face of the earth by the keen comiDetition of the pouchless mammals.
Up to the day, then, when Captain Cook and Sir Joseph Banks, landing for the first time on the coast of New South "Wales, saw an animal with short front limbs, huge hind legs, a monstrous tail, and a curious habit of hopping along the ground (called by the natives a kangaroo), the opossums of America were the only pouched mammals known to the European world in any part of the explored continents. Australia, severed from the rest of the earth — penitus toto orbe divisa — ever since the end of the second- ary period, remained as yet, so to speak, in the secondary age so far as its larger life-elements were concerned, and presented to the first comers a certain vague and indefinite picture of what " the world before the flood " must have looked like. Only it was a very remote flood ; an antediluvian age separated from our own not by thousands but by millions of seasons.
To this rough approximate statement, however, sundry needful qualifications must be made at the very outset. No statement is
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ever quite correct until you have contradicted in minute detail about two thirds of it.
In the first place there are a good many modern elements in the indigenous population of Australia ; but then they are ele- ments of the stray and casual sort one always finds even in remote oceanic islands. They are waifs wafted by accident from other places. For example, the fl^ora is by no means exclusively an an- cient flora, for a considerable number of seeds and fruits and spores of ferns always get blown by the wind, or washed by the sea, or carried on the feet or feathers of birds, from one part of the world to another. In all these various ways, no doubt, modern plants from the Asiatic region have invaded Australia at difi:erent times, and altered to some extent the character and aspect of its original native vegetation. Nevertheless, even in the matter of its plants and trees, Australia must still be considered a very old- fashioned and stick-in-the-mud continent. The strange puzzle- monkeys, the quaint- jointed casuarinas (like horse-tails grown into big willows), and the park-like forests of blue-gum trees, with their smooth stems robbed of their outer bark, impart a marvel- ously antiquated and unfamiliar tone to the general appearance of Australian woodland. All these types belong by birth to classes long since extinct in the larger continents. The scrub shows no turfy greensward; grasses, which elsewhere carpet the ground, were almost unknown till introduced from Europe ; in the wild lands, bushes and undershrubs of ancient aspect cover the soil, remarkable for their stifle, dry, wiry foliage, their vertically instead of horizontally flattened leaves, and their general dead blue-green or glaucous color. Altogether, the vegetation itself, though it contains a few more modern forms than the animal world, is still essentially antique in type, a strange survival from the forgotten flora of the chalk age, the oolite, and even the lias.
Again, to winged animals, such as birds and bats and flying insects, the ocean forms far less of a barrier than it does to quad- rupeds, to reptiles, and to fresh-water fishes. Hence Australia has, to some extent, been invaded by later types of birds and other fly- ing creatures, who live on there side by side with the ancient ani- mals of the Secondary pattern. Warblers, thrushes, fly-catchers, shrikes, and crows must all be comparatively recent immigrants from the Asiatic mainland. Even in this respect, however, the Australian life-region still bears an antiquated and undeveloped aspect. Nowhere else in the world do we find those very oldest types of birds represented by the cassowaries, the emus, and the mooruk of New Britain. The extreme term in this exceedingly ancient set of creatures is given us by the wingless bird, the apteryx or kiwi of New Zealand, whose feathers nearly resemble hair, and whose grotesque appearance makes it as much a wonder
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in its own class as the puzzle-monkey and the casnarina are among forest-trees. No feathered creatures so closely approach the lizard - tailed birds of the oolite or the toothed birds of the Cretaceous period as do these Australian and New Zealand emus and apte- ryxes. Again, while many characteristic Oriental families are quite absent, like the vultures, woodpeckers, pheasants, and bul- buls, the Australian region has many other fairly ancient birds, found nowhere else on the surface of our modern planet. Such are the so-called brush-turkeys and mound-builders, the only feathered things that never sit upon their own eggs, but allow them to be hatched after the fashion of reptiles, by the heat of the sand or of fermenting vegetable matter. The piping crows, the honey-suckers, the lyre-birds, and the more-porks are all peculiar to the Austra- lian region. So are the wonderful and aesthetic bower-birds. Brush-tongued lories, black cockatoos, and gorgeously colored pigeons, though somewhat less antique, perhaps, in type, give a special character to the bird-life of the country. And in New Guinea, an isolated bit of the same old continent, the birds-of- paradise, found nowhere else in the whole world, seem to recall some forgotten Eden of the remote past, some golden age of Sa- turnian splendor. Poetry apart, into which I have dropped for a moment like Mr. Silas Wegg, the birds-of-paradise are, in fact, gorgeously dressed crows, specially adapted to forest-life in a rich fruit-bearing tropical country, where food is abundant and ene- mies unknown.
Last of all, a certain small number of modern mammals have passed over to Australia at various times by pure chance. They fall into two classes — the rats and mice, who doubtless got trans- ported across on floating logs or balks of timber ; and the human importations, including the dog, who came, perhaps, on their own canoes, perhaps on the wreck and debris of inundations. Yet even in these cases, again, Australia still maintains its proud pre- eminence as the most antiquated and unprogressive of continents. For the Australian black-fellow must have got there a very long time ago, indeed ; he belongs to an extremely ancient human type, and strikingly recalls in his jaws and skull the Neanderthal sav- age and other early prehistoric races ; while the woolly-headed Tasmanian, a member of a totally distinct human family, and, perhaps, the very lowest sample of humanity that has survived to modern times, must have crossed over to Tasmania even earlier still, his brethren on the mainland having, no doubt, been exter- minated later on, when the stone-age Australian black-fellows first got cast ashore upon the continent inhabited by the yet more bar- baric and helpless negritto race. As for the dingo, or Australian wild dog, only half domesticated by the savage natives, he repre- sents a low ancestral dog type, half wolf and half jackal, incapa-
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ble of tlie higher canine traits, and with, a suspicions, ferocious, glaring eye, that betrays at once his uncivilizable tendencies.
Omitting these later importations, however — the modern plants, birds, and human beings — it may be fairly said that Australia is still in its Secondary stage, while the rest of the world has reached the Tertiary and Quaternary periods. Here, again, however, a deduction must be made, in order to attain the necessary accuracy. Even in Australia the world never stands still. Though the Aus- tralian animals are still at bottom the European and Asiatic ani- mals of the Secondary age, they are those animals with a dijffer- ence. They have undergone an evolution of their own. It has not been the evolution of the great continents ; but it has been evolution all the same; slower, more local, narrower, more re- stricted, yet evolution in the truest sense. One might compare the difference to the difference between the civilization of Europe and the civilization of Mexico or Peru, The Mexicans, when Cor- tes blotted out their indigenous culture, were still, to be sure, in their stone age ; but it was a very different stone age from that of the cave-dwellers or the mound-builders in Britain. Even so, though Australia is still zoologically in the Secondary period, it is a Secondary period a good deal altered and adapted in detail to meet the wants of special situations.
The oldest types of animals in Australia are the ornithorhyn- chus and the echidna, the " beast with a bill " and the " porcupine ant-eater " of popular natural history. These curious creatures, genuine living fossils, occupy in some respects an intermediate place between the mammals on the one hand and the birds and lizards on the other. The echidna has no teeth, and a very bird- like skull and body ; the ornithorhynchus has a bill like a duck's, webbed feet, and a great many quaint anatomical peculiarities which closely ally it to the birds and reptiles. Both, in fact, are early arrested stages in the development of mammals from the old common vertebrate ancestor ; and they could only have struggled on to our own day in a continent free from the severe competition of the higher types which have since been evolved in Europe and Asia. Even in Australia itself the ornithorhynchus and echidna have had to put up perforce with the lower places in the hierarchy of Nature, The first is a burrowing and aquatic creature, special- ized in a thousand minute ways for his amphibious life and queer subterranean habits ; the second is a spiny, hedgehog-like noctur- nal prowler, who buries himself in the earth during the day, and lives by night on insects which he licks up greedily with his long, ribbon-like tongue. Apart from the specializations brought about by their necessary adaptation to a particular niche in the economy of life, these two quaint and very ancient animals probably pre- serve for us in their general structure the features of an extremely
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early descendant of the common ancestor from whom mammals, birds, and reptiles alike are originally derived.
The ordinary Australian pouched mammals belong to far less ancient types than ornithorhynchus and echidna, but they too are very old in structure, though they have undergone an extraordi- nary separate evolution to fit them for the most diverse positions in life. Almost every main form of higher mammal (except the biggest ones) has, as it were, its analogue or representative among the marsupial fauna of the Australasian region fitted to fill the same niche in nature. For instance, in the blue-gum forests of New South Wales, a small animal inhabits the trees, in form and aspect exactly like a flying - squirrel. Nobody who was not a structural and anatomical naturalist would ever for a moment dream of doubting its close affinity to the flying-squirrels of the American woodlands. It has just the same general outline, just the same bushy tail, just the same rough arrangement of colors, and just the same expanded parachute-like membrane stretching between the fore and hind limbs. Why should this be so ? Clearly because both animals have independently adapted themselves to the same mode of life under the same general circumstances. Natural selection, acting upon unlike original types, but in like conditions, has produced in the end very similar results in both cases. Still, when we come to examine the more intimate under- lying structure of the two animals, a profound fundamental differ- ence at once exhibits itself. The one is distinctly a true squirrel, a rodent of the rodents, externally adapted to an arboreal exist- ence ; the other is equally a true phalanger, a marsupial of the marsupials, which has independently undergone on his own ac- count very much the same adaptation, for very much the same reasons. Just so a dolphin looks externally very like a fish, in head and tail and form and movement ; its flippers closely resem- ble fins ; and nothing about it seems to differ very markedly from the outer aspect of a shark or a codfish. But in reality it has no gills and no swim-bladder ; it lays no eggs ; it does not own one truly fish-like organ. It breathes air, it possesses lungs, it has warm blood, it suckles its young ; in heart and brain and nerves and organization it is a thorough-going mammal, with an acquired resemblance to the fishy form, due entirely to mere similarity in place of residence.
Running hastily through the chief marsupial developments, one may say that the wombats are pouched animals who take the place of rabbits or marmots in Europe, and resemble them both in burrowing habits and more or less in shape, which closely ap- proaches the familiar and ungraceful guinea-pig outline. The vul- pine phalanger does duty for a fox ; the fat and sleepy little dor- mouse phalanger takes the place of a European dormouse. Both
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are so ridiculously like the analogous animals of the larger conti- nents that the colonists always call them, in perfect good faith, by the familiar names of the old-country creatures. The koala poses as a small bear ; the cuscus answers to the raccoons of America. The pouched badgers explain themselves at once by their very name, like the Plyants, the Pinchwifes, the Brainsicks, and the Carelesses of the Restoration comedy. The "native rabbit" of Swan River is a rabbit - like bandicoot ; the pouched ant-eater similarly takes the place of the true ant-eater of other continents. By way of carnivores, the Tasmanian devil is a fierce and savage marsupial analogue of the American wolverine ; a smaller species of the same type usurps the name and place of the marten ; and the dog-headed thylacinus is in form and figure precisely like a wolf or a jackal. The pouched weasels are very weasel-like ; the kangaroo rats and kangaroo mice run the true rats and mice a close race in every particular. And it is worth notice, in this con- nection, that the one marsupial family which could compete with higher American life, the opossums, are, so to speak, the monkey development of the marsupial race. They have opposable thumbs, which make their feet almost into hands ; they have prehensile tails, by which they hang from branches in true monkey fashion ; they lead an arboreal omnivorous existence ; they feed off fruits, birds' eggs, insects, and roots ; and altogether they are just active, cunning, intelligent, tree-haunting marsupial spider-monkeys.
Australia has also one still more ancient denizen than any of these, a living fossil of the very oldest sort, a creature of wholly immemorial and primitive antiquity. The story of its discovery teems with the strangest romance of natural history. To those who could appreciate the facts of the case it was just as curious and just as interesting as though we were now to discover some- where in an unknown island or an African oasis some surviving mammoth, some belated megatherium, or some gigantic and mis- shapen liassic saurian. Imagine the extinct animals of the Crys- tal Palace grounds suddenly appearing to our dazzled eyes in a tropical ramble, and you can faintly conceive the delight and astonishment of naturalists at large when the barramunda first " swam into their ken " in the rivers of Queensland. To be sure, in size and shape this " extinct fish," still living and grunting quietly in our midst, is comparatively insignificant beside the " dragons of the prime " immortalized in a famous stanza by Tennyson: but to the, true enthusiast, size is nothing; and the barramunda is just as much a marvel and a monster as the Atlan- tosaurus himself would have been if he had suddenly walked upon the stage of time, dragging fifty feet of lizard-like tail in a train behind him. And this is the plain story of that marvelous dis- covery of a " missing link " in our own pedigree.
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In the oldest Secondary rocks of Britain and elsewhere there occur in abundance the teeth of a genus of ganoid fishes known as the Ceratodi. (I apologize for ganoid, though it is not a swear- word.) These teeth reappear from time to time in several sub- sequent formations, but at last slowly die out altogether ; and of course all naturalists naturally concluded that the creature to which they belonged had died out also, and was long since num- bered with the dodo and the mastodon. The idea that a ceratodus could still be living, far less that it formed an important link in the development of all the higher animals, could never for a moment have occurred to anybody. As well expect to find a palaeolithic man quietly chipping flints on a Pacific atoll, or to discover the ancestor of all horses on the isolated and crag-encir- cled summit of Roraima, as to unearth a real live ceratodus from a modern estuary. In 1870, however^ Mr. Krefft took away the breath of scientific Europe by informing it that he had found the extinct ganoid swimming about as large as life, and six feet long, without the faintest consciousness of its own scientific importance, in a river of Queensland at the present day. The unsophisticated aborigines knew it as barramunda ; the almost equally ignorant white settlers called it with irreverent and unfilial contempt the flat-head. On further examination, however, the desj)ised barra- munda proved to be a connecting link of primary rank between the oldest surviving group of fishes and the lowest air-breathing animals like the frogs and salamanders. Though a true fish, it leaves its native streams at night, and sets out on a foraging expedition after vegetable food in the neighboring woodlands. There it browses on myrtle leaves and grasses, and otherwise be- haves itself in a manner wholly unbecoming its piscine anteced- ents and aquatic education. To fit it for this strange amphibious life, the barramunda has both lungs and gills ; it can breathe either air or water at will, or, if it chooses, the two together. Though covered with scales, and most fish-like in outline, it pre- sents points of anatomical resemblance both to salamanders and liz- ards ; and, as a connecting bond between the North American mud- fish on the one hand and the wonderful lepidosiren on the other, it forms a true member of the long series by which the higher animals generally trace their descent from a remote race of marine ancestors. It is very interesting, therefore, to find that this living fossil link between fish and reptiles should have survived only in the fossil continent, Australia. Everyvfhere else it has long since been beaten out of the field by its own more developed amphibian descendants ; in Australia alone it still drags on a lonely existence as the last relic of an otherwise long-forgotten and extinct fam- ily. — CornJiill Magazine.