I need scarce say how slow and interrupted in both provinces the course of arrangement has been, or how often succeeding writers have had to undo what their predecessors had done, only to have their own classifications set aside by their successors in turn. At length, however, when the work appears to be well nigh completed, a new science has arisen, which presents us with a very wonderful means of testing it. Cowley, in his too eulogistic ode to Hobbes,—smit by the singular ingenuity of the philosophic infidel, and unable to look through his sophisms to the consequences which they involved,—could say, in addressing him, that

"only God could know Whether the fair idea he did show Agreed entirely with God's own or no."

And he then not very wisely added,—

"This, I dare boldly tell, 'T is so like truth, 't will serve our turn as well."

We now know, however, that no mere resemblance to truth will for any considerable length of time serve its turn. It is because the resemblances have, like those of Hobbes, been mere resemblances, that so much time and labor have had to be wasted by the pioneers of science in their removal; and, now that a wonderful opportunity has occurred of comparing, in this matter of classification, the human with the Divine idea,—the idea embodied by the zoologists and botanists in their respective systems, with the idea embodied by the Creator of all in geologic history,—we cannot perhaps do better, in entering upon our subject, than to glance briefly at the great features in which God's order of classification, as developed in Palaeontology, agrees with the order in which man has at length learned to range the living productions, plant and animal, by which he is surrounded, and of which he himself forms the most remarkable portion. In an age in which a class of writers not without their influence in the world of letters would fain repudiate every argument derived from design, and denounce all who hold with Paley and Chalmers as anthropomorphists, that labor to create for themselves a god of their own type and form, it may be not altogether unprofitable to contemplate the wonderful parallelism which exists between the Divine and human systems of classification, and—remembering that the geologists who have discovered the one had no hand in assisting the naturalists and phytologists who framed the other—soberly to inquire whether we have not a new argument in the fact for an identity in constitution and quality of the Divine and human minds,—not a mere fanciful identity, the result of a disposition on the part of man to imagine to himself a God bearing his own likeness, but an identity real and actual, and the result of that creative act by which God formed man in his own image.

The study of plants and animals seems to have been a favorite one with thoughtful men in every age of the world. According to the Psalmist, these great "works of the Lord are sought out of all them that have pleasure therein." The Book of Job, probably the oldest writing in existence, is full of vivid descriptions of the wild denizens of the flood and desert; and it is expressly recorded of the wise old king, that he "spake of trees, from the cedar tree that is in Lebanon, even unto the hyssop that springeth out of the wall; and also of beasts, and of fowl, and of creeping things, and of fishes." Solomon was a zoologist and botanist; and there is palpable classification in the manner in which his studies are described. It is a law of the human mind, as has been already said, that, wherever a large stock of facts are acquired, the classifying principle steps in to arrange them. "Even the rudest wanderer in the fields," says Dr. Brown, "finds that the profusion of blossoms around him—in the greater number of which he is able himself to discover many striking resemblances—may be reduced to some order of arrangement." But, for many centuries, this arranging faculty labored but to little purpose. As specimens of the strange classification that continued to obtain down till comparatively modern times, let us select that of two works which, from the literary celebrity of their authors, still possess a classical standing in letters,—Cowley's "Treatise on Plants," and Goldsmith's "History of the Earth and Animated Nature." The plants we find arranged by the poet on the simple but very inadequate principle of size and show. Herbs are placed first, as lowest and least conspicuous in the scale; then flowers; and, finally, trees. Among the herbs, at least two of the ferns—the true maidenhair and the spleenwort—are assigned places among plants of such high standing as sage, mint, and rosemary: among the flowers, monocotyledons, such as the iris, the tulip, and the lily, appear among dicotyledons, such as the rose, the violet, the sunflower, and the auricula: and among trees we find the palms placed between the plum and the olive; and the yew, the fir, and the juniper, flanked on one side by the box and the holly, and on the other by the oak. Such, in treating of plants, was the classification adopted by one of the most learned of English poets in the year 1657.

Nor was Goldsmith,-who wrote more than a century later, much more fortunate in dealing with the animal kingdom. Buffon had already published his great work; and even he could bethink him of no better mode of dividing his animals than into wild and tame. And in Goldsmith, who adopted, in treating of the mammals, a similar principle, we find the fishes and molluscs placed, in advance of the sauroid, ophidian, and batrachian reptiles,—the whale united in close relationship to the sharks and rays,—animals of the tortoise kind classed among animals of the lobster kind, and both among shell fish, such as the snail, the nautilus, and the oyster. And yet Goldsmith was engaged on his work little more than eighty years ago. In fine, the true principles of classification in the animal kingdom are of well nigh as recent development as geologic science itself, and not greatly more ancient in even the vegetable kingdom. It would, of course, be wholly out of place to attempt giving a minute history here of the progress of arrangement in either department; but it can scarce be held that the natural system of plants was other than very incomplete previous to 1789, when Jussieu first enunciated his scheme of classification; nor did it receive its later improvements until so late as 1846, when, after the publication, in succession, of the schemes of De Candolle and Endlicher, Lindley communicated his finished system to the world. And there certainly existed no even tolerably perfect system of zoology until 1816, when the "Animal Kingdom" of Cuvier appeared. Later naturalists,—such as Agassiz, in his own special department, the history of fishes, and Professor Owen in the invertebrate divisions,—have improved on the classification of even the great Frenchman; but for purposes of comparison between the scheme developed in geologic history and that at length elaborated by the human mind, the system of Cuvier will be found, for at least our present purpose, sufficiently complete. And in tracing through time the course of the vegetable kingdom, let us adopt, as our standard to measure it by, the system of Lindley.

Commencing at the bottom of the scale, we find the Thallogens, or flowerless plants which lack proper stems and leaves,—a class which includes all the algae. Next succeed the Acrogens, or flowerless plants that possess both stems and leaves,—such as the ferns and their allies. Next, omitting an inconspicuous class, represented by but a few parasitical plants incapable of preservation as fossils, come the Endogens,—monocotyledonous flowering plants, that include the palms, the liliaceae, and several other families, all characterized by the parallel venation of their leaves. Next, omitting another inconspicuous tribe, there follows a very important class,—the Gymnogens,—polycotyledonous trees, represented by the conifers; and cycadaceae. And, last of all, come the Dicotyledonous Exogens,—a class to which all our fruit, and what are known as our "forest trees," belong, with a vastly preponderating majority of the herbs and flowers that impart fertility and beauty to our gardens and meadows. This last class, though but one, now occupies much greater space in the vegetable kingdom than all the others united.

Such is the arrangement of Lindley, or rather an arrangement the slow growth of ages, to which this distinguished botanist has given the last finishing touches. And let us now mark how closely it resembles the geologic arrangement as developed in the successive stages of the earth's history.



-+ - Thallogens. Silurian. Acrogens. -+ -+ - Gymnogens. Old Red. -+ -+ -+ - Monocotyledons. Carboniferous. -+ -+ -+ -+ - Permian. -+ -+ -+ -+ - Triassic. -+ -+ -+ -+ - : Dicotyledons. Oolitic. : -+ -+ -+ -+ -+- Cretaceous. -+ -+ -+ -+ -+- Dicotyledonous Trees. Tertiary. -+ -+ -+ -+ -+- Geologic [Thal. Ac. Gy. Mon. Dic.] arrangement. Lindley's [Thal. Ac. Mon. Gy. Dic.] arrangement.

THE GENEALOGY OF PLANTS.]

The most ancient period of whose organisms any trace remains in the rocks seems to have been, prevailingly at least, a period of Thallogens. We must, of course, take into account the fact, that it has yielded no land plants, and that the sea is everywhere now, as of old, the great habitat of the algae,—one of the four great orders into which the Thallogens are divided. There appear no traces of a terrestrial vegetation until we reach the uppermost beds of the Upper Silurian System. But, account for the fact as we may, it is at least worthy of notice, that, alike in the systems of our botanists and in the chronological arrangements of our geologists, the first or introductory class which occurs in the ascending order is this humble Thallogenic class. There is some trace in the Lower Silurians of Scotland of a vegetable structure which may have belonged to one of the humbler Endogens, of which, at least, a single genus, the Zosteraceae, still exists in salt water; but the trace is faint and doubtful, and, even were it established, it would form merely a solitary exception to the general evidence that the first known period of vegetable existence was a period of Thallogens. The terrestrial remains of the Upper Silurians of England, the oldest yet known, consist chiefly of spore-like bodies, which belonged, says Dr. Hooker, to Lycopodiaceae,—an order of the second or acrogenic class. And, in the second great geologic period,—that of the Old Red Sandstone,—we find this second class not inadequately represented. In its lowest fossiliferous beds we detect a Lycopodite which not a little resembles one of the commonest of our club mosses,—Lycopodium clavatum,—with a minute fern and a large striated plant resembling a calamite, and evidently allied to an existing genus of Acrogens, the equisetaceae. In the Middle Old Red Sandstone there also occurs a small fern, with some trace of a larger; and one of its best preserved vegetable organisms is a lepidodendron,—an extinct ally of the Lycopodiums; while in the upper beds of the system, especially as developed in the south of Ireland, the noble fern known as Cyclopteris Hibernicus is very abundant. This fern has been detected also in the Upper Old Red of our own country, mingled with fragments of contemporary calamites. With, however, these earliest plants of the land yet known, there occurs a true wood, which belonged, as shown by its structure, to a gymnospermous or polycotyledonous tree, and which we find associated with remains of Coccosteus and Diplacanthus.



And here let me remark, that the facts of Palaeontological science compel us to blend, in some degree, with the classification of our modern botanists, that of the botanists of an earlier time. In a passage already quoted, Solomon is said to have discoursed of plants, "from the cedar tree that is in Lebanon, to the hyssop that springeth out of the wall,"—from the great tree to the minute herb; and Cowley rose, in his metrical treatise, as has been shown, from descriptions of herbs and flowers to descriptions of fruit and forest trees. And as in every age in which there existed a terrestrial vegetation there seem to have been "trees" as certainly as "herbs," the palaeontological botantist finds that he has, in consequence, to range his classes, not in one series, but in two,—the Gymnogens, or cone-bearing trees, in a line nearly parallel with the Acrogens, or flowerless, spore-bearing herbs. But the arrangement is in no degree the less striking from the circumstance that it is ranged, not in one, but in two lines. It is, however, an untoward arrangement for the purposes of the Lamarckian, whose peculiar hypothesis would imperatively demand, not a double, but a single column, in which the ferns and club mosses would stand far in advance, in point of time, of the Coniferae. In the Coal Measures, so remarkable for the great luxuriance of their flora, both the Gymnogens and Acrogens are largely developed, with a very puzzling intermediate class, that, while they attained to the size of trees, like the former, retained in a remarkable degree, as in the Lepidodendra and the Calamites, the peculiar features of the latter. And with these there appear, though more sparingly, the Endogens,—monocotyledonous plants, represented by a few palm-like trees (Palmacites), a few date-like fruits (Trigonocarpum), and a few grass-like herbs (Poacites). In the great Secondary division, the true dicotyledonous plants first appear; but, so far as is yet known, no dicotyledonous wood. In the earlier formations of the division a degree of doubt attaches to even the few leaves of this class hitherto detected; but in the Lower Cretaceous strata they become at once unequivocal in their character, and comparatively abundant, both as individuals and species; and in the Tertiary deposits they greatly outnumber all the humbler classes, and appear not only as herbs, but also as great trees. Not, however, until shortly before the introduction of man do some of their highest orders, such as the Rosaceae, come upon the scene, as plants of that great garden—including the fields of the agriculturist—which it has been part of man's set task upon earth to keep and to dress. And such seems to be the order of classification in the vegetable kingdom, as developed in creation, and determined by the geologic periods.

-+ -+ -+ - Rad. Art. Mol. Silurian. Fishes. -+ -+ -+ -+ - Old Red. Reptiles. -+ -+ -+ -+ -+ - Carboniferous. -+ -+ -+ -+ -+ - Permian. -+ -+ -+ -+ -+ - Triassic. -+ -+ -+ -+ -+ - Birds. Oolitic. : Mammals. : -+ -+ -+ -+ -+ -+ -+ - : Cretaceous. : : -+ -+ -+ -+ -+ -+ -+ - Pla. Mam. Tertiary. -+ -+ -+ -+ -+ -+ -+ -+- Recent. Man. -+ -+ -+ -+ -+ -+ -+ -+- Geologic [Rad. Art. Mol. Fish. Rep. Bird. Mam. Man.] Arrangement. Cuvier's [Rad. Art. Mol. Fish. Rep. Bird. Mam. Man.] Arrangement.

THE GENEALOGY OF ANIMALS.]

The parallelism which exists between the course of creation, as exhibited in the animal kingdom, and the classification of the greatest zoologist of modern times, is perhaps still more remarkable. Cuvier divides all animals into vertebrate and invertebrate; the invertebrates consisting, according to his arrangement, of three great divisions,—mollusca, articulata, and radiata; and the vertebrates, of four great classes,—the mammals, the birds, the reptiles, and the fishes. From the lowest zone at which organic remains occur, up till the higher beds of the Lower Silurian System, all the animal remains yet found belong to the invertebrate divisions. The numerous tables of stone which compose the leaves of this first and earliest of the geologic volumes correspond in their contents with that concluding volume of Cuvier's great work in which he deals with the mollusca, articulata, and radiata; with, however, this difference, that the three great divisions, instead of occurring in a continnous series, are ranged, like the terrestrial herbs and trees, in parallel columns. The chain of animal being on its first appearance is, if I may so express myself, a threefold chain;—a fact nicely correspondent with the further fact, that we cannot in the present creation range serially, as either higher or lower in the scale, at least two of these divisions,—the mollusca and articulata. In one of the higher beds of the Upper Silurian System,—a bed which borders on the base of the Old Red Sandstone,—the vertebrates make their earliest appearance in their fourth or ichthyic class; and we find ourselves in that volume of the geologic record which corresponds to Cuvier's volume on the fishes. In the many-folded pages of the Old Red Sandstone, till we reach the highest and last, there occur the remains of no other vertebrates than those of this fourth class; but in its uppermost deposits there appear traces of the third or reptilian class; and in passing upwards still, through the Carboniferous, Permian, and Triassic Systems, we find reptiles continuing the master existences of the time. The geologic volume in which these great formations are included corresponds to the Cuvierian one devoted to the Reptilia. Early in the Oolitic System, birds, Cuvier's second class of the vertebrata, make their first appearance, though their remains, like those of birds in the present time, are rare and infrequent; and, for at least the earlier periods of their existence, we know that they were,—that they haunted for food the waters of the period, and waded in their shallows,—only from marks similar to those by which Crusoe became first aware of the visits paid to his island by his savage neighbors,—their footprints, left impressed on the sands over which they stalked of old. This early Oolitic volume corresponds in its contents to the section devoted by Cuvier, in his great work, to his second class, the birds. And in the Stonisfield slate,—a deposit interposed between the "Inferior" and "Great Oolites," we detect the earliest indications of his first or mammaliferous class, apparently represented, however, by but one order,—the Marsupiata, or pouched animals, to whose special place in the scale I shall afterwards have occasion to refer. Not until we reach the times of the Tertiary division do the mammals in their higher orders appear. The great Tertiary volume corresponds to those volumes of Cuvier which treat of the placental animals that suckle their young. And finally,—last born of creation,—man appears upon the scene, in his several races and varieties; the sublime arch of animal being at length receives its keystone; and the finished work stands up complete, from foundation to pinnacle, at once an admirably adjusted occupant of space, and a wonderful monument of Divine arrangement and classification, as it exists in time. Save at two special points, to which I shall afterwards advert, the particular arrangement unfolded by geologic history is exactly that which the greatest and most philosophic of the naturalists had, just previous to its discovery, originated and adopted as most conformable to nature: the arrangements of geologic history as exhibited in time, if, commencing at the earliest ages, we pursue it downwards, is exactly that of the "Animal Kingdom" of Cuvier read backwards.

Let us then, in grappling with the vast multiplicity of our subject, attempt reducing and simplifying it by means of the classifying principle; not simply, however,—again to recur to the remark of the metaphysician,—as an internal principle given us by nature, but as an external principle exemplified by nature. Let us take the organisms of the old geologic periods in the order in which they occur in time; secure, as has been shown, that if our chronology be correct, our classification will, as a consequence, be good. It will be for the natural theologians of the coming age to show the bearing of this wonderful fact on the progress of man towards the just and the solid, and on the being and character of man's Creator,—to establish, on the one hand, against the undue depreciators of intellect and its results, that in certain departments of mind, such as that which deals with the arrangement and development of the scheme of organic being, human thought is not profitlessly revolving in an idle circle, but progressing Godwards, and gradually unlocking the order of creation. And, on the other hand, it will be equally his proper business to demand of the Pantheist how,—seeing that only persons (such as the Cuviers and Lindleys) could have wrought out for themselves the real arrangement of this scheme,—how, I say, or on what principle, it is to be held that it was a scheme originated and established at the beginning, not by a personal, but by an impersonal God. But our present business is with the fact of the parallel arrangements, Divine and human,—not with the inferences legitimately deducible from it.



Beginning with the plants, let us, however, remark, that they do not precede in the order of their appearance the humbler animals. No more ancient organism than the Oldhamia of the Lowest Irish Silurians, a plant-like zoophyte somewhat resembling our modern sertularia, has yet been detected by the geologist; though only a few months ago the researches of Mr. Salter in the ancient rocks of the Longmynd, Shropshire, previously deemed unfossiliferous, have given, to it what seem to be contemporary vegetable organisms, in a few ill-preserved fucoids. So far as is yet known, plants and animals appear together. The long upward march of the animal kingdom takes its departure at its starting point from a thick forest of algae. In Bohemia, in Norway, in Sweden, in the British Islands, in North America, wherever, in fine, what appears to be the lowest, or at least one of the lowest, zones of life has yet been detected, the rocks are found to be darkened by the remains of algae, so abundantly developed in some cases, that they compose, as in the ancient Lower Silurians of Dumfriesshire, impure beds of anthracite several feet in thickness. Apparently, from the original looseness of their texture, the individual plants are but indifferently preserved; nor can we expect that organisms so ancient should exhibit any very close resemblance to the plants which darken the half-tide rocks and skerries of our coasts at the present time. We do detect, however, in some of these primordial fossils, at least a noticeable likeness to families familiar to the modern algaeologist. The cord-like plant, Chorda filum, known to our children as "dead men's ropes," from its proving fatal at times to the too adventurous swimmer who gets entangled in its thick wreaths, had a Lower Silurian representative, known to the Palaeontologist as the Palaeochorda, or ancient chorda, which existed apparently in two species,—a larger and smaller. The still better known Chondrus crispus, the Irish moss or carrageen of our cookery-books, has likewise its apparent though more distant representative in Chondritis, a Lower Silurian algae, of which there seems to exist at least three species. The fucoids, or kelp weeds, appear to have had also their representatives in such plants as Fucoides gracilis of the Lower Silurians of the Malverns; in short, the Thallogens of the first ages of vegetable life seem to have resembled, in the group, and in at least their more prominent features, the algae of the existing time. And with the first indications of land we pass direct from the Thallogens to the Acrogens,—from the sea weeds to the fern allies. The Lycopodiaceae;, or club mosses, bear in the axils of their leaves minute circular cases, which form the receptacles of their spore-like seeds. And when, high in the Upper Silurian System, and just when preparing to quit it for the Lower Old Red Sandstone, we detect our earliest terrestrial organisms, we find that they are composed exclusively of those little spore receptacles. The number of land plants gradually increases as we ascend into the overlying system. Still, however, the Flora of even the Old Red is but meagre and poor; and you will perhaps permit me to lighten this part of my subject, which threatens too palpably to partake of the poverty of that with which it deals, by a simple illustration.



We stand, at low ebb, on the outer edge of one of those iron-bound shores of the Western Highlands, rich in forests of algae, from which, not yet a generation bygone, our Celtic proprietors used to derive a larger portion of their revenues than from their fields and moors. Rock and skerry are brown with sea weed. The long cylindrical lines of Chorda filum, many feet in length, lie aslant in the tideway; long shaggy bunches of Fucus serratus and Fucus nodosus droop heavily from the rock sides; while the flatter ledges, that form the uneven floor upon which we tread, bristle thick with the stiff, cartilaginous, many-cleft fronds of at least two species of chondrus,—the common carrageen, and the smaller species, C. Norvegicus. Now, in the thickly-spread fucoids of this Highland shore we have not a very inadequate representation of the first, or thallogenic vegetation,—that of the great Silurian period, as exhibited in the rocks, from the base to nearly the top of the system. And should we add to the rocky tract, rich in fucoids, a submarine meadow of pale shell sand, covered by a deep green swathe of zostera, with its jointed saccharine roots and slim flowers, unfurnished with petals, we would render it perhaps more adequately representative still.



We cross the beach, and enter on a bare brown moor, comparatively fertile, however, in the club mosses. One of the largest and finest of the species, Lycopodium clavatum, with its long scaly stems and upright spikes of lighter green,—altogether a graceful though flowerless plant, which the herd-boy learns to select from among its fellows, and to bind round his cap,—goes trailing on the drier spots for many feet over the soil; while at the edge of trickling runnel or marshy hollow, a smaller and less hardy species, Lycopodium inundatum, takes its place. The marshes themselves bristle thick with the deep green horse tail, Equisetum fluviatile, with its fluted stem and verticillate series of linear brandies. Two other species of the same genus, Equisetum sylvaticum and Equisetum arvense, flourish on the drier parts of the moor, blent with two species of minute ferns, the moonwort and the adder's tongue,—ferns that, like the magnificent royal fern (Osmunda regalis), though on a much humbler scale, bear their seed cases on independent stems, and were much sought after of old for imaginary virtues, which the modern schools of medicine refuse to recognize. Higher up the moor, ferns of ampler size occur, and what seems to be rushes, which bear atop conglobate panicles on their smooth leafless stems; but at its lower edge little else appears than the higher Acrogens,—ferns and their allies. There occurs, however, just beyond the first group of club mosses,—a remarkable exception in a solitary pine,—the advance guard of one of the ancient forests of the country, which may be seen far in the background, clothing with its shaggy covering of deep green the lower hill-slopes. And as we found in the Thallogens of that littoral zone over which we have just passed, representatives of the marine flora of the Silurian System, from the first appearance of organisms in its nether beds, to its bone-bed of the Upper Ludlow rocks, in which the Lycopodites first appear, so in the Acrogens of that moor, with its solitary coniferous tree, we may recognize an equally striking representative of the terrestrial flora which existed during the deposition of these Ludlow rocks, and of the various formations of the Old Red Sandstone, Lower, Middle, and Upper.



In the upper beds of the Upper Silurian, as has been already remarked, Lycopodites are the only terrestrial plants yet found. In the Lower Old Red Sandstone we find added to these, with Thallogens that bear at least the same general character as in the system beneath, minute ferns, and a greatly larger plant, allied to the horse tails. The Old Red flora seems to have been prevailingly an acrogenic flora; and yet with almost its first beginnings,—contemporary with at least the earlier fossils of the system in Scotland, we find a true polycotyledonous tree, not lower in the scale than the araucarites of the Coal Measures,—which in structure it greatly resembles,—or than the pines or cedars of our own times (see Fig. 3). In the Middle Old Red Sandstone there occurs, with plants representative apparently of the ferns and their allies, a somewhat equivocal and doubtful organism, which may have been the panicle or compound fruit of some aquatic rush; while in the Upper Old Red, just ere the gorgeous flora of the Coal Measures began to be, there existed in considerable abundance a stately fern, the Cyclopteris Hibernicus (see Fig. 2), of mayhap not smaller proportions than our monarch of the British ferns, Osmunda regalis, associated with a peculiar lepidodendron, and what seems to be a lepidostrobus,—possibly the fructiferous spike or cone of the latter, mingled with carbonaceous stems, which, in the simplicity of their texture, and their abundance, give evidence of a low but not scanty vegetation. Ere passing to the luxuriant carboniferous flora, I shall make but one other remark. The existing plants whence we derive our analogies in dealing with the vegetation of this early period, contribute but little, if at all, to the support of animal life. The ferns and their allies remain untouched by the grazing animals. Our native club mosses, though once used in medicine, are positively deleterious; the horse tails, though harmless, so abound in silex, which wraps them round with a cuticle of stone, that they are rarely cropped by cattle; while the thickets of fern which cover our hill-sides, and seem so temptingly rich and green in their season, scarce support the existence of a single creature, and remain untouched in stem and leaf, from their first appearance in spring, until they droop and wither under the frosts of early winter. Even the insects that infest the herbaria of the botanist almost never injure his ferns. Nor are our resin-producing conifers, though they nourish a few beetles, favorites with the herbivorous tribes in a much greater degree. Judging from all we yet know, the earliest terrestrial flora may have covered the dry land with its mantle of cheerful green, and served its general purposes, chemical and others, in the well-balanced economy of nature; but the herb-eating animals would have fared but ill even where it throve most luxuriantly; and it seems to harmonize with the fact of its non-edible character, that up to the present time we know not that a single herbivorous animal lived among its shades. From all that appears, it may be inferred that it had not to serve the purposes of the floras of the passing time, in which, according to the poet,

"The world's bread depends on the shooting of a seed."



The flora of the Coal Measures was the richest and most luxuriant, in at least individual productions, with which the fossil botanist has formed any acquaintance. Never before or since did our planet bear so rank a vegetation as that of which the numerous coal seams and inflammable shales of the carboniferous period form but a portion of the remains,—the portion spared, in the first instance, by dissipation and decay, and in the second by the denuding agencies. Almost all our coal,—the stored up fuel of a world,—forms but a comparatively small part of the produce of this wonderful flora. Amid much that was so strange and antique of type in its productions as to set the analogies of the botanist at fault, there occurred one solitary order, not a few of whose species closely resembled their cogeners of the present time. I refer, of course, to its ferns. And these seem to have formed no small proportion of the entire flora of the period. Francis estimates the recent dorsiferous ferns of Great Britain at thirty-five species, and the species of all the other genera at six more,—forty-one species in all; and as the flowering plants of the country do not fall short of fourteen hundred species, the ferns bear to them the rather small proportion of about one to thirty-five; whereas of the British Coal Measure flora, in which we do not yet reckon quite three hundred species of plants, about a hundred and twenty were ferns. Three sevenths of the entire carboniferous flora of Britain belonged to this familiar class; and for about fifty species more we can discover no nearer analogies than those which connect them with the fern allies. And if with the British Coal Measure we include those also of the Continent of America, we shall find the proportions in favor of the ferns still greater. The number of carboniferous plants hitherto described amounts, says M. Ad. Brogniart, to about five hundred, and of these two hundred and fifty,—one half of the whole,—were ferns.



]



Rising in the scale from the lower to the higher vegetable forms of the system,—from its ferns to its trees,—we find great conifers,—so great that they must have raised their heads more than a hundred feet over the soil; and such was their abundance in this neighborhood, that one can scarce examine a fragment of coal beside one's household fire that is not charged with their carbonized remains. Though marked by certain peculiarities of structure, they bore, as is shown by the fossil trunks of Granton and Craigleith, the familiar outlines of true coniferous trees; and would mayhap have differed no more in appearance from their successors of the same order that now live in our forests, than these differ from the conifers of New Zealand or of New South Wales. We have thus, in the numerous ferns and numerous coniferous trees of the Coal Measures, known objects by which to conceive of some of the more prominent features of the flora of which they composed so large a part. We have not inadequate conceptions of at once the giants of its forests and the green swathe of its plains and hill-sides,—of its mighty trees and its dwarf underwood,—of its cedars of Lebanon, so to speak, and its hyssop of the wall. But of an intermediate class we have no existing representatives; and in this class the fossil botanist finds puzzles and enigmas with which hitherto at least he has been able to deal with only indifferent success. There is a view, however, sufficiently simple, which may be found somewhat to lessen, if not altogether remove, the difficulty. Nature does not dwell willingly in mediocrity; and so in all ages she as certainly produced trees, or plants of tree-like proportions and bulk, as she did minute shrubs and herbs. In not a few of the existing orders and families, such as the Rosaceae, the Leguminosae, the Myrtaceae, and many others, we have plants of all sizes, from the creeping herb, half hidden in the sward, to the stately tree. The wild dwarf strawberry and minute stone-bramble are of the same order as our finer orchard trees,—apple, pear, and plum,—or as those noble hawthorn, mountain ash, and wild cherry trees, that impart such beauty to our lawns and woods; and the minute spring vetch and everlasting pea are denizens of the same great family as the tall locust and rosewood trees, and the gorgeous laburnum. Did there exist no other plants than the Rosaceae or the Leguminosae, we would possess, notwithstanding, herbs, shrubs, and trees, just as we do now. And in plants of a greatly humbler order we have instances of similar variety in point of size. The humblest grass in our meadows belongs to the same natural order as the tall bamboo, that, shooting up its panicles amid the jungles of India to the height of sixty feet, looks down upon all the second class trees of the country. Again, the minute forked spleenwort of Arthur Seat, which rarely exceeds three inches in length, is of the same family as those tree-ferns of New Zealand and Tasmania that rise to an elevation of from twenty to thirty feet. And we know how in the ferns provision is made for the attainment and maintenance of the tree-like size and character. The rachis, which in the smaller species is either subterranean or runs along the ground, takes in the tree-fern a different direction, and, rising erect, climbs slowly upwards in the character of a trunk or stem, and sends out atop, year after year, a higher and yet higher coronal of fronds. And in order to impart the necessary strength to this trunk, and to enable it to war for ages with the elements, its mass of soft cellular tissue is strengthened all round by internal buttresses of dense vascular fibre, tough and elastic as the strongest woods. Now, not a few of the more anomalous forms of the Coal Measures seem to be simply fern allies of the types Lycopodiaceae, Marsileaceae, and Equisetum, that, escaping from the mediocrity of mere herbs, shot up into trees,—some of them very great trees,—and that had of necessity to be furnished with a tissue widely different from that of their minuter contemporaries and successors. It was of course an absolute mechanical necessity, that if they were to present, by being tall and large, a wide front to the tempest, they should also be comparatively solid and strong to resist it; but with this simple mechanical requirement there seems to have mingled a principle of a more occult character. The Gymnogens or conifers were the highest vegetable existences of the period,—its true trees; and all the tree-like fern allies were strengthened to meet the necessities of their increased size, on, if I may so speak, a coniferous principle. Tissue resembling that of their contemporary conifers imparted the necessary rigidity to their framework; nay, so strangely were they pervaded throughout by the coniferous characteristics, that it seems difficult to determine whether they really most resembled the acrogenous or gymnogenous families. The Lepidodendra,—great plants of the club moss type, that rose from fifty to seventy feet in height,—had well nigh as many points of resemblance to the coniferae as to the Lycopodites. The Calamites,—reed-like, jointed plants, that more nearly resemble the Equisetaceae than aught else which now exists, but which attained, in the larger specimens, to the height of ordinary trees, also manifest very decidedly, in their internal structure, some of the characteristics of the conifers. It has been remarked by Lindley and Hutton of even Sphenophyllum,—a genus of plants with verticillate leaves, of which at least six species occur in our Coal Measures, and which Brogniart refers to one of the humblest families of the fern allies,—that it seems at least as nearly related to the Coniferae as to its lowlier representatives, the Marsileaceae. And it is this union of traits, pertaining to what are now widely separated orders, that imparts to not a few of the vegetables of the Coal Measures their singularly anomalous character.



(Asophila perrotetiana.)]



(Cyathea.)]



]



Let me attempt introducing you more intimately to one of those plants which present scarce any analogy with existing forms, and which must have imparted so strange a character and appearance to the flora of the Coal Measures. The Sigillaria formed a numerous genus of the Carboniferous period: no fewer than twenty-two different species have been enumerated in the British coal fields alone; and such was their individual abundance, that there are great seams of coal which seem to be almost entirely composed of their remains. At least the ancient soil on which these seams rest, and on which their materials appear to have been elaborated from the elements, is in many instances as thickly traversed by their underground stems as the soil occupied by our densest forests is traversed by the tangled roots of the trees by which it is covered; and we often find associated with them in these cases the remains of no other plant. The Sigillaria were remarkable for their beautifully sculptured stems, various in their pattern, according to their species. All were fluted vertically, somewhat like columns of the Grecian Doric; and each flute or channel had its line of sculpture running adown its centre. In one species (S. flexuosa) the sculpture consists of round knobs, surrounded by single rings, like the heads of the bolts of the ship carpenter; in another (S. reniformis) the knobs are double, and of an oval form, somewhat resembling pairs of kidneys,—a resemblance to which the species owes its name. In another species (S. catenulata) what seems a minute chain of distinctly formed elliptical links drops down the middle of each flute; in yet another (S. oculata) the carvings are of an oval form, and, bearing each a round impression in its centre, they somewhat resemble rows of staring goggle-eyes; while the carvings in yet another species (S. pachyderma) consist chiefly of crescent-shaped depressions. The roots, or rather underground stems, of this curious genus attracted notice, from their singularity, long ere their connection with the carved and fluted stems had been determined, and have been often described as the "stigmaria" of the fossil botanist. They, too, have their curious carvings, consisting of deeply marked stigmata, quincuncially arranged, with each a little ring at its bottom, and, in at least one rare species, surrounded by a sculptured star. Unlike true roots, they terminate abruptly; each rootlet which they send forth was jointed to the little ring or dimpled knob at the bottom of the stigmata; and the appearance of the whole, as it radiated from the central mass, whence the carved trunk proceeded, somewhat resembled that of an enormous coach-wheel divested of the rim. Unfortunately we cannot yet complete our description of this strange plant. A specimen, traced for about forty feet across a shale bed, was found to bifurcate atop into two great branches,—a characteristic in which, with several others, it differed from most of the tree-ferns,—a class of plants to which Adolphe Brogniart is inclined to deem it related; but no specimen has yet shown the nature of its foliage. I am, however, not a little disposed to believe with Brogniart that it may have borne as leaves some of the supposed ferns of the Coal Measures; nowhere, at least, have I found these lie so thickly, layer above layer, as around the stems of Sigillaria; and the fact that, even in our own times, plants widely differing from the tree-ferns,—such, for instance, as one of the Cycadeae,—should bear leaves scarce distinguishable from fern fronds, may well reconcile us to an apparent anomaly in the case of an ancient plant such as Sigillaria, whose entire constitution, so far as it has been ascertained, appears to have been anomalous. The sculpturesque character of this richly fretted genus was shared by not a few of its contemporaries. The Ulodendra, with their rectilinear rows of circular scars, and their stems covered with leaf-like carvings, rivalled in effect the ornately relieved torus of a Corinthian column: Favularia, Knorria, Halonia, many of the Calamites, and all the Lepidodendra, exhibited the most delicate sculpturing. In walking among the ruins of this ancient flora, the Palaeontologist almost feels as if he had got among the broken fragments of Italian palaces, erected long ages ago, when the architecture of Rome was most ornate, and every moulding was roughened with ornament; and in attempting to call up in fancy the old Carboniferous forests, he has to dwell on this peculiar feature as one of the most prominent, and to see, in the multitude of trunks darkened above by clouds of foliage, that rise upon him in the prospect, the slim columns of an elder Alhambra, roughened with arabesque tracery and exquisite filagree work.



In the Oolitic flora we find a few peculiar features introduced. The Cyeadeae,—a family of plants allied to the ferns on the one hand, and to the conifers on the other, and which in their general aspect not a little resemble stunted palms,—appear in this flora for the first time. Its coniferous genera, too, receive great accessions to their numbers, and begin to resemble, more closely than at an earlier period, the genera which still continue to exist. The cypresses, the yews, the thujas, the dammaras, all make their earliest appearance in the flora of the Oolite. Among our existing woods there seem to be but two conifers (that attain to the dignity of trees) indigenous to Britain,—the common yew, Taxus baccata, and the common Scotch fir, Pinus sylvestris; and yet we know that the latter alone formed, during the last few centuries, great woods, that darkened for many miles together the now barren moors and bare hill-sides of the Highlands of Scotland,—moors and hill-sides that, though long since divested of their last tree, are still known by their old name of forests. In the times of the Oolite, on the other hand, Britain had from fourteen to twenty different species of conifers; and its great forests, of whose existence we have direct evidence in the very abundant lignites of the system, must have possessed a richness and variety which our ancient fir woods of the historic or human period could not have possessed. With the Conifers and the Cycadeae there were many ferns associated,—so many, that they still composed nearly two fifths of the entire flora; and associated with these, though in reduced proportions, we find the fern allies. The reduction, however, of these last is rather in species than in individuals. The Brora Coal, one of the most considerable Oolitic seams in Europe, seems to have been formed almost exclusively of an equisetum,—E. columnare. In this flora the more equivocal productions of the Coal Measures are represented by what seems to be the last of the Calamites; but it contains no Lepidodendra,—no Ulodendra,—no Sigillaria,—no Favularia,—no Knorria or Halonia. Those monsters of the vegetable world that united to the forms of its humbler productions the bulk of trees, had, with the solitary exception of the Calamites, passed into extinction; and ere the close of the system they too had disappeared. The forms borne by most of the Oolitic plants were comparatively familiar forms. With the Acrogens and Gymnogens we find the first indication of the Liliaceae, or lily-like plants,—of plants, too, allied to the Pandanaceae or screw pines, the fruits of which are sometimes preserved in a wonderfully perfect state of keeping in the Inferior Oolite, together with Carpolithes,—palm-like fruits, very ornately sculptured,—and the remains of at least one other monocotyledon, that bears the somewhat general name of an Endogenite. With these there occur a few disputed leaves, which I must persist in regarding as dicotyledonous. But they formed, whatever their true character, a very inconspicuous feature in the Oolitic flora; and not until the overlying Cretaceous System is ushered in do we find leaves in any considerable quantity decidedly of this high family; nor until we enter into the earlier Tertiaries do we succeed in detecting a true dicotyledonous tree. On such an amount of observation is this order of succession determined,—though the evidence is, of course, mainly negative,—that when, some eight or ten years ago, Dr. John Wilson, the learned Free Church missionary to the Parsees of India, submitted to me specimens of fossil woods which he had picked up in the Egyptian Desert, in order that I might if possible determine their age, I told him, ere yet the optical lapidary had prepared them for examination, that if they exhibited the coniferous structure, they might belong to any geologic period from the times of the Lower Old Red Sandstone downwards; but that if they manifested in their tissue the dicotyledonous character, they could not be older than the times of the Tertiary. On submitting them in thin slices to the microscope, they were found to exhibit the peculiar dicotyledonous structure as strongly as the oak or chestnut. And Lieutenant Newbold's researches in the deposit in which they occur has since demonstrated, on stratigraphical evidence, that not only does it belong to the great Tertiary division, but also to one of the comparatively modern formations of the Tertiary.



(Reduced one third.)]



(Miocene of OEningen.)]



(Miocene of Bohemia.)]



The earlier flora of this Tertiary division presents an aspect widely different from that of any of the previous ones. The ferns and their allies sink into their existing proportions; nor do the coniferae, previously so abundant, occupy any longer a prominent place. On the other hand, the dicotyledonous herbs and trees, previously so inconspicuous in creation, are largely developed. Trees of those Amentiferous orders to which the oak, the hazel, the beech, and the plane belong, were perhaps not less abundant in the Eocene woods than in those of the present time: they were mingled with trees of the Laurel, the Leguminous, and the Anonaceous or custard apple families, with many others; and deep forests, in the latitude of London (in which the intertropical forms must now be protected, as in the Crystal Palace, with coverings of glass, and warmed by artificial heat), abounded in graceful palms. Mr. Bowerbank found in the London clay of the island of Sheppey alone the fruits of no fewer than thirteen different species of this picturesque family, which lends so peculiar a feature to the landscapes in which it occurs; and ascertained that the undergrowth beneath was composed, in large proportion, of creeping plants of the gourd and melon order. From the middle or Miocene flora of the Tertiary division,—of which we seem to possess in Britain only the small but interesting fragment detected by his Grace the Duke of Argyll among the trap-beds of Mull,—most of the more exotic forms seem to have been excluded. The palms, however, still survive in no fewer than thirty-one different species, and we find in great abundance, in the place of the other exotics, remains of the plane and buckthorn families,—part of a group of plants that in their general aspect, as shown in the Tertiary deposits of the Continent, not a little resembled the vegetation of the United States at the present day. The nearer we approach to existing times, the more familiar in form and outline do the herbs and trees become. We detect, as has been shown, at least one existing order in the ferns of the Coal Measures; we detect at least existing genera among the Coniferae, Equisetaceae, and Cycadaceae of the Oolite; the acacias, gourds, and laurels of the Eocene flora, and the planes, willows, and buckthorns of the Miocene, though we fail to identify their species with aught that now lives, still more strongly remind us of the recent productions of our forests or conservatories; and, on entering, in our downward course, the Pleistocene period, we at length find ourselves among familiar species. On old terrestrial surfaces, that date before the times of the glacial period, and underlie the boulder clay, the remains of forests of oak, birch, hazel, and fir have been detected,—all of the familiar species indigenous to the country, and which still flourish in our native woods. And it was held by the late Professor Edward Forbes, that the most ancient of his five existing British floras,—that which occurs in the south-west of Ireland, and corresponds with the flora of the northwest of Spain and the Pyrenees,—had been introduced into the country as early, perhaps, as the times of the Miocene. Be this, however, as it may, there can rest no doubt on the great antiquity of the prevailing trees of our indigenous forests.

The oak, the birch, the hazel, the Scotch fir, all lived, I repeat, in what is now Britain, ere the last great depression of the land. The gigantic northern elephant and rhinoceros, extinct for untold ages, forced their way through their tangled branches; and the British tiger and hyaena harbored in their thickets. Cuvier framed an argument for the fixity of species on the fact that the birds and beasts embalmed in the catacombs were identical in every respect with the animals of the same kinds that live now. But what, it has been asked, was a brief period of three thousand years, compared with the geologic ages? or how could any such argument be founded on a basis so little extended? It is, however, to no such narrow basis we can refer in the case of these woods. All human history is comprised in the nearer corner of the immense period which they measure out; and yet, from their first appearance in creation till now they have not altered a single fibre. And such, on this point, is the invariable testimony of Palaeontologic science,—testimony so invariable, that no great Palaeontologist was ever yet an asserter of the development hypothesis. With the existing trees of our indigenous woods it is probable that in even these early times a considerable portion of the herbs of our recent flora would have been associated, though their remains, less fitted for preservation, have failed to leave distinct trace behind them. We at least know generally, that with each succeeding period there appeared a more extensively useful and various vegetation than that which had gone before. I have already referred to the sombre, unproductive character of the earliest terrestrial flora with which we are acquainted. It was a flora unfitted, apparently, for the support of either graminivorous bird or herbivorous quadruped. The singularly profuse vegetation of the Coal Measures was, with all its wild luxuriance, of a resembling cast. So far as appears, neither flock nor herd could have lived on its greenest and richest plains; nor does even the flora of the Oolite seem to have been in the least suited for the purposes of the shepherd or herdsman. Not until we enter on the Tertiary periods do we find floras amid which man might have profitably labored as a dresser of gardens, a tiller of fields, or a keeper of flocks and herds. Nay, there are whole orders and families of plants of the very first importance to man which do not appear until late in even the Tertiary ages. Some degree of doubt must always attach to merely negative evidence; but Agassiz, a geologist whose statements must be received with respect by every student of the science, finds reason to conclude that the order of the Rosaceae,—an order more important to the gardener than almost any other, and to which the apple, the pear, the quince, the cherry, the plum, the peach, the apricot, the victorine, the almond, the raspberry, the strawberry, and the various brambleberries belong, together with all the roses and the potentillas,—was introduced only a short time previous to the appearance of man. And the true grasses,—a still more important order, which, as the corn-bearing plants of the agriculturist, feed at the present time at least two thirds of the human species, and in their humbler varieties form the staple food of the grazing animals,—scarce appear in the fossil state at all. They are peculiarly plants of the human period.

Let me instance one other family of which the fossil botanist has not yet succeeded in finding any trace in even the Tertiary deposits, and which appears to have been specially created for the gratification of human sense. Unlike the Rosaceae, it exhibits no rich blow of color, or tempting show of luscious fruit;—- it does not appeal very directly to either the sense of taste or of sight: but it is richly odoriferous; and, though deemed somewhat out of place in the garden for the last century and more, it enters largely into the composition of some of our most fashionable perfumes. I refer to the Labiate family,—a family to which the lavenders, the mints, the thymes, and the hyssops belong, with basil, rosemary, and marjoram,—all plants of "gray renown," as Shenstone happily remarks in his description of the herbal of his "Schoolmistress."

"Herbs too she knew, and well of each could speak, That in her garden sipped the silvery dew, Where no vain flower disclosed a gaudy streak, But herbs for use and physic not a few, Of gray renown within those borders grew. The tufted basil, pun-provoking thyme, And fragrant balm, and sage of sober hue.

"And marjoram sweet in shepherd's posie found, And lavender, whose spikes of azure bloom Shall be erewhile in arid bundles bound, To lurk amid her labors of the loom, And crown her kerchiefs clean with meikle rare perfume.

"And here trim rosemary, that whilom crowned The daintiest garden of the proudest peer, Ere, driven from its envied site, it found A sacred shelter for its branches here, Where, edged with gold, its glittering skirts appear, With horehound gray, and mint of softer green."

All the plants here enumerated belong to the labiate family; which, though unfashionable even in Shenstone's days, have still their products favorably received in the very best society. The rosemary, whose banishment from the gardens of the great he specially records, enters largely in the composition of eau de Cologne. Of the lavenders, one species (Lavendula vera) yields the well known lavender oil, and another (L. latifolio) the spike oil. The peppermint (Meantha viridus) furnishes the essence so popular under that name among our confectioners; and one of the most valued perfumes of the East (next to the famous Attar, a product of the Rosaceae) is the oil of the Patchouly plant, another of the labiates. Let me indulge, ere quitting this part of the subject, in a single remark. There have been classes of religionists, not wholly absent from our own country, and well known on the Continent, who have deemed it a merit to deny themselves every pleasure of sense, however innocent and delicate. The excellent but mistaken Pascal refused to look upon a lovely landscape; and the Port Royalist nuns remarked, somewhat simply for their side of the argument, that they seemed as if warring with Providence, seeing that the favors which he was abundantly showering upon them, they, in obedience to the stern law of their lives, were continually rejecting. But it is better, surely, to be on the side of Providence against Pascal and the nuns, than on the side of Pascal and the nuns against Providence. The great Creator, who has provided so wisely and abundantly for all his creatures, knows what is best for us, infinitely better than we do ourselves; and there is neither sense nor merit, surely, in churlishly refusing to partake of that ample entertainment, sprinkled with delicate perfumes, garnished with roses, and crowned with the most delicious fruit, which we now know was not only specially prepared for us, but also got ready, as nearly as we can judge, for the appointed hour of our appearance at the feast. This we also know, that when the Divine Man came into the world,—unlike the Port Royalists, he did not refuse the temperate use of any of these luxuries, not even of that "ointment of spikenard, very precious" (a product of the labiate family), with which Mary anointed his feet.



Though it may at first seem a little out of place, let us anticipate here, for the sake of the illustration which it affords, one of the sections of the other great division of our subject,—that which treats of the fossil animals. Let us run briefly over the geologic history of insects, in order that we may mark the peculiar light which it casts on the character of the ancient floras. No insects have yet been detected in the Silurian or Old Red Sandstone Systems. They first appear amid the hard, dry, flowerless vegetation of the Coal Measures, and in genera suited to its character. Among these the scorpions take a prominent place,—carnivorous arachnidae of ill repute, that live under stones and fallen trunks, and seize fast with their nippers upon the creatures on which they prey, crustaceans usually, such as the wood-louse, or insects, such as the earth-beetles and their grubs. With the scorpions there occur cockroaches of types not at all unlike the existing ones, and that, judging from their appearance, must have been foul feeders, to which scarce anything could have come amiss as food. Books, manuscripts, leather, ink, oil, meat, even the bodies of the dead, are devoured indiscriminately by the recent Blatta gigantea of the warmer parts of the globe,—one of the most disagreeable pests of the European settler, or of war vessels on foreign stations. I have among my books an age-embrowned copy of Ramsay's "Tea Table Miscellany," that had been carried into foreign parts by a musical relation, after it had seen hard service at home, and had become smoke dried and black; and yet even it, though but little tempting, as might be thought, was not safe from the cockroaches; for, finding it left open one day, they ate out in half an hour half its table of contents, consisting of several leaves. Assuredly, if the ancient Blattae were as little nice in their eating as the devourers of the "Tea Table Miscellany," they would not have lacked food amid even the unproductive flora and meagre fauna of the Coal Measures. With these ancient cockroaches a few locusts and beetles have been found associated, together with a small Tinea,—a creature allied to the common clothes-moth, and a Phasmia,—a creature related to the spectre insects. But the group is an inconsiderable one; for insects seem to have occupied no very conspicuous place in the carboniferous fauna. The beetles appear to have been of the wood and seed devouring kinds, and would probably have found their food among the conifers; the Phasmidae and grasshoppers would have lived on the tender shoots of the less rigid plants their contemporaries; the Tinea, probably on ligneous or cottony fibre. Not a single insect has the system yet produced of the now numerous kinds that seek their food among flowers. In the Oolitic ages, however, insects become greatly more numerous,—so numerous that they seemed to have formed almost exclusively the food of the earliest mammals, and apparently also of some of the flying reptiles of the time. The magnificent dragon-flies, the carnivorous tyrants of their race, were abundant; and we now know, that while they were, as their name indicates, dragons to the weaker insects, they themselves were devoured by dragons as truly such as were ever yet feigned by romancer of the middle ages. Ants were also common, with crickets, grasshoppers, bugs both of the land and water, beetles, two-winged flies, and, in species distinct from the preceding carboniferous ones, the disgusting cockroaches. And for the first time amid the remains of a flora that seems to have had its few flowers,—though flowers could have formed no conspicuous feature in even an Oolitic landscape,—we detect in a few broken fragments of the wings of butterflies, decided trace of the flower-sucking insects. Not, however, until we enter into the great Tertiary division do these become numerous. The first bee makes its appearance in the amber of the Eocene, locked up hermetically in its gem-like tomb,—an embalmed corpse in a crystal coffin,—along with fragments of flower-bearing herbs and trees. The first of the Bombycidae too,—insects that maybe seen suspended over flowers by the scarce visible vibrations of their wings, sucking the honied juices by means of their long, slender trunks,—also appear in the amber, associated with moths, butterflies, and a few caterpillars. Bees and butterflies are present in increased proportions in the latter Tertiary deposits: but not until that terminal creation to which we ourselves belong was ushered on the scene did they receive their fullest development. There is exquisite poetry in Wordsworth's reference to "the soft murmur of the vagrant bee,"—

"A slender sound, yet hoary Time Doth to the soul exalt it with the chime Of all his years; a company Of ages coming, ages gone, Nations from before them sweeping."

And yet, mayhap, the naked scientific facts of the history of this busy insect are scarcely less poetic than the pleasing imagination of the poet regarding it. They tell that man's world, with all its griefs and troubles, is more emphatically a world of flowers than any of the creations that preceded it, and that as one great family—the grasses—were called into existence, in order, apparently, that he might enter in favoring circumstances upon his two earliest avocations, and be in good hope a keeper of herds and a tiller of the ground; and as another family of plants—the Rosaceae—was created in order that the gardens which it would be also one of his vocations to keep and to dress should have their trees "good for food and pleasant to the taste;" so flowers in general were profusely produced just ere he appeared, to minister to that sense of beauty which distinguishes him from all the lower creatures, and to which he owes not a few of his most exquisite enjoyments. The poet accepted the bee as a sign of high significance: the geologist also accepts her as a sign. Her entombed remains testify to the gradual fitting up of our earth as a place of habitation for a creature destined to seek delight for the mind and the eye as certainly as for the grosser senses, and in especial marks the introduction of the stately forest trees, and the arrival of the delicious flowers. And,

"Thus in their stations lifting toward the sky The foliaged head in cloud-like majesty, The shadow-casting race of trees survive: Thus in the train of spring arrive Sweet flowers: what living eye hath viewed Their myriads? endlessly renewed Wherever strikes the sun's glad ray, Where'er the subtile waters stray, Wherever sportive zephyrs bend Their course, or genial showers descend."



LECTURE SECOND.

THE PALAEONTOLOGICAL HISTORY OF ANIMALS.

Amid the unceasing change and endless variety of nature there occur certain great radical ideas, that, while they form, if I may so express myself, the groundwork of the change,—the basis of the variety,—admit in themselves of no change or variety whatever. They constitute the aye-enduring tissue on which the ever-changing patterns of creation are inscribed: the patterns are ever varying; the tissue which exhibits them for ever remains the same. In the animal kingdom, for instance, the prominent ideas have always been uniform. However much the faunas of the various geologic periods may have differed from each other, or from the fauna which now exists, in their general aspect and character, they were all, if I may so speak, equally underlaid by the great leading ideas which still constitute the master types of animal life. And these leading ideas are four in number. First, there is the star-like type of life,—life embodied in a form that, as in the corals, the sea-anemones, the sea-urchins, and the star-fishes, radiates outwards from a centre; second, there is the articulated type of life,—life embodied in a form composed, as in the worms, crustaceans, and insects, of a series of rings united by their edges, but more or less moveable on each other; third, there is the bilateral or molluscan type of life,—life embodied in a form in which there is a duality of corresponding parts, ranged, as in the cuttle-fishes, the clams, and the snails, on the sides of a central axis or plane; and fourth, there is the vertebrate type of life,—life embodied in a form in which an internal skeleton is built up into two cavities placed the one over the other; the upper for the reception of the nervous centres, cerebral and spinal,—the lower for the lodgment of the respiratory, circulatory, and digestive organs. Such have been the four central ideas of the faunas of every succeeding creation, except perhaps the earliest of all, that of the Lower Silurian System, in which, so far as is yet known, only three of the number existed,—the radiated, articulated, and molluscan ideas or types. That Omnipotent Creator, infinite in his resources,—who, in at least the details of his workings, seems never yet to have repeated himself, but, as Lyell well expresses it, breaks, when the parents of a species have been moulded, the dye in which they were cast,—manifests himself, in these four great ideas, as the unchanging and unchangeable One. They serve to bind together the present with all the past; and determine the unity of the authorship of a wonderfully complicated design, executed on a groundwork broad as time, and whose scope and bearing are deep as eternity.

The fauna of the Silurian System bears in all its three great types the stamp of a fashion peculiarly antique, and which, save in a few of the mollusca, has long since become obsolete. Its radiate animals are chiefly corals, simple or compound, whose inhabitants may have somewhat resembled the sea-anemones; with zoophites, akin mayhap to the sea-pens, though the relationship must have been a remote one; and numerous crinoids, or stone lilies, some of which consisted of but a sculptured calyx without petals, while others threw off a series of long, flexible arms, that divided and subdivided like the branches of a tree, and were thickly fringed by hair-like fibres. There is great variety and beauty among these Silurian crinoids; and, from the ornate sculpture of their groined and ribbed capitals and slender columns, the Gothic architect might borrow not a few striking ideas.



The difference between the older and newer fashions, as exemplified in the cup-shaped corals, may be indicated in a single sentence. The ancient corals were stars of four rays, or of multiples of four; the modern corals are stars of six rays, or of multiples of six. But though, at a certain definite period,—that during which the great Palaeozoic division ended and the Secondary division began—nature, in forming this class of creatures, discarded the number four, and adopted instead the number six, the great leading idea of the star itself was equally retained in corals of the modern as in those of the more ancient type.



The articulata of the Silurian period bore a still more peculiar character. They consisted mainly of the Trilobites,—a family in whose nicely-jointed shells the armorer of the middle ages might have found almost all the contrivances of his craft, anticipated, with not a few besides which he had failed to discover; and which, after receiving so immense a development during the middle and later times of the Silurian period, that whole rocks were formed almost exclusively of their remains, gradually died out in the times of the Old Red Sandstone, and disappeared for ever from creation after the Carboniferous Limestone had been deposited. The Palaeontologist knows no more unique family than that of the Trilobites, or a family more unlike any which now exists, or a family which marks with more certainty the early rocks in which they occur. And yet, though formed in a fashion that perished myriads of ages ago, how admirably does it not exhibit the articulated type of being, and illustrate that unity of design which, amid endless diversity, pervades all nature. The mollusca of the Silurians ranged from the high cephalopoda, represented in our existing seas by the nautili and the cuttle-fishes, to the low brachipods, some of whose congeners may still be detected in the terebratula of our Highland lochs and bays, and some in the lingulae of the southern hemisphere. The cephalopods of the system are all of an obsolete type, that disappeared myriads of ages ago,—a remark which, with the exceptions just intimated, and perhaps one or two others, applies equally to its brachipods; but of at least two of its intermediate families,—the gasteropoda and lamellibranchiata,—several of the forms resemble those of recent shells of the temperate latitudes. In its general aspect, however, the Silurian fauna, antiquely fashioned, as I have said, as became its place in the primeval ages of existence, was unlike any other which the world ever saw; and the absence of the vertebrata, or at least the inconspicuous place which they occupied if they were at all present, must have imparted to the whole, as a group, a humble and mediocre character. It seems to have been for many ages together a creation of molluscs, corals, and Crustacea. At length, in an upper bed of the system, immediately under the base of the Old Red Sandstone, the remains of the earliest known fishes appear, blent with what also appears for the first time,—the fragmentary remains of a terrestrial vegetation. The rocks beneath this ancient bone-bed have yielded, as I have already said, no trace of any plant higher than the Thallogens, or at least not higher than the Zosteracea,—plants whose proper habitat is the sea; but, through an apparently simultaneous advance of the two kingdoms, animal and vegetable,—though of course the simultaneousness may be but merely apparent,—the first land plants and the first vertebrates appear together in the same deposit.

What, let us inquire, is the character of these ancient fishes, that first complete the scale of animated nature in its four master ideas, by adding the vertebrate to the invertebrate divisions? So far as is yet known, they all consist of one well marked order,—that placoidal order of Agassiz that to an internal framework of cartilage adds an external armature, consisting of plates, spines, and shagreen points of solid bone. Either of the two kinds of dog-fishes on our coasts,—the spiked or spotted,—maybe accepted as not inadequate representatives of this order as it now exists. The Port Jackson shark, however,—a creature that to the dorsal spines and shagreen-covered skin of the common dog-fish adds a mouth terminal at the snout, not placed beneath, as in most other sharks, and a palate covered with a dense pavement of crushing teeth,—better illustrates the order as it first appeared in creation than any of our British placoids.



- Silurian. -+ -Placoid. Ganoid. Old Red. -+ + Carboniferous. -+ + Permian. -+ + Triassic. -+ + Oolitic. -+ + + + Cretaceous. Ctenoid and Cycloid. -+ + + + Tertiary. -+ + + + Geologic [Pla. Gan. Cte. Cyc.] arrangement. Agassiz's [Pla. Gan. Cte. Cyc.] arrangement.

THE GENEALOGY OF FISHES.]



And here let me adduce another and very remarkable instance of the correspondence which obtains between the sequence in which certain classes of organisms were first ushered into being, and the order of classification adopted, after many revisions, by the higher naturalists. Cuvier, with not a few of the ichthyologists who preceded him, arranged the fishes into two distinct series,—the Cartilaginous and Osseous; and these last he mainly divided into the hard or spiny-finned fishes, and the soft or joint-finned fishes. He placed the sturgeon in his Cartilaginous series; while in his soft-finned order he found a place for the Polypterus of the Nile and the Lepidosteus of the Ohio and St. Lawrence. But the arrangement, though it seemed at the time one of the best and most natural possible, failed to meet any corresponding arrangement in the course of geologic history. The place assigned to the class of fishes as a whole corresponded to their place in the Palaeontological scale;—- first of the vertebrate division in the order of their appearance, they border, as in the "Animal Kingdom" of the naturalist, on the invertebrate divisions. But it was not until the new classification of Agassiz had ranged them after a different fashion that the correspondence became complete in all its parts. First, he erected the fishes that to an internal cartilaginous skeleton unite an external armature of plates and points of bone, into his Placoid order; next, gathering together a mere handful of individuals from among the various orders and families over which they had been scattered,—the sturgeons from among the cartilaginous fishes, and the lepidosteus and polypterus from among the Clupia or herrings,—he erected into a small ganoid order all the fishes that are covered, whatever the consistency of their skeleton, by a continuous or nearly continuous armor of enamelled bone, or by great bony plates that lock into each other at their edges. Out of the remaining fishes,—those covered with scales of a horny substance, and which now comprise nearly nine tenths of the whole class,—he erected two orders more,—a Ctenoid order, consisting of fishes whose scales, like those of the perch, are pectinated at their lower edges like the teeth of a comb, and a Cycloid order, composed of fishes whose scales, like those of the salmon, are defined all around by a simple continuous margin; and no sooner was the division effected than it was found to cast a singularly clear light on the early history of the class. The earliest fishes—firstborn of their family—seem to have been all placoids. The Silurian System has not yet afforded trace of any other vertebral animal. With the Old Red Sandstone the ganoids were ushered upon the scene in amazing abundance; and for untold ages, comprising mayhap millions of years, the entire ichthyic class consisted, so far as is yet known, of but these two orders. During the times of the Old Red Sandstone, of the Carboniferous, of the Permian, of the Triassic, and of the Oolitic Systems, all fishes, though apparently as numerous individually as they are now, were comprised in the ganoidal and placoidal orders. The period of these orders seems to have been nearly correspondent with the reign, in the vegetable kingdom, of the Acrogens and Gymnogens, with the intermediate classes, their allies. At length, during the ages of the Chalk, the Cycloids and Ctenoids were ushered in, and were gradually developed in creation until the human period, in which they seem to have reached their culminating point, and now many times exceed in number and importance all other fishes. We do not see a sturgeon (our British representative of the ganoids) once in a twelvemonth; and though the skate and dog-fish (our representatives of the placoids) are greatly less rare, their number bears but a small proportion to that of the fishes belonging to the two prevailing orders, of which thousands of boat-loads are landed on our coasts every day.

The all but entire disappearance of the ganoids from creation is surely a curious and not unsuggestive circumstance. In the human family there are races that have long since reached their culminating point, and are now either fast disappearing or have already disappeared. The Aztecs of Central America, or the Copts of the valley of the Nile, are but the inconsiderable fragments of once mighty nations, memorials of whose greatness live in the vast sepulchral mounds of the far West, or in the temples of Thebes or Luxor, or the pyramids of Gizah. But in the rivers of these very countries,—in the Polypterus of the Nile, or the Lepidosteus of the Mississippi,—we are presented with the few surviving fragments of a dynasty compared with which that of Egypt or of Central America occupied but an exceedingly small portion of either space or time. The dynasty of the ganoids was at one time coextensive with every river, lake, and sea, and endured during the unreckoned eons which extended from the times of the Lower Old Red Sandstone until those of the Chalk. I may here mention, that as there are orders of plants, such as the Rosaceae and the Grasses, that scarce preceded man in their appearance, so there are families of fishes that seem peculiarly to belong to the human period. Of these, there is a family very familiar on our coasts, and which, though it furnishes none of our higher ichthyic luxuries, is remarkable for the numbers of the human family which it provides with a wholesome and palatable food. The delicate Salmonidae and the Pleuronectidae,—families to which the salmon and turbot belong,—were ushered into being as early as the times of the Chalk; but the Gadidae or cod family,—that family to which the cod proper, the haddock, the dorse, the whiting, the coal-fish, the pollock, the hake, the torsk, and the ling belong, with many other useful and wholesome species,—did not precede man by at least any period of time appreciable to the geologist. No trace of the family has yet been detected in even the Tertiary rocks.



Of the ganoids of the second age of vertebrate existence,—that of the Old Red Sandstone,—some were remarkable for the strangeness of their forms, and some for constituting links of connection which no longer exist in nature, between the ganoid and placoid orders. The Acanth family, which ceased with the Coal Measures, was characterized, especially in its Old Red species, by a combination of traits common to both orders; and among the extremer forms, in which Palaeontologists for a time failed to detect that of the fish at all, we reckon those of the genera Coccosteus, Pterichthys, and Cephalaspis. The more aberrant genera, however, even while they consisted each of several species, were comparatively short lived. The Coccosteus and Cephalaspis were restricted to but one formation apiece; while the Pterichthys, which appears for the first time in the lower deposits of the Old Red Sandstone, becomes extinct at its close. On the other hand, some of the genera that exemplified the general type of their class were extremely long lived. The Celacanths were reproduced in many various species, from the times of the Lower Old Red Sandstone to those of the Chalk; and the Cestracions, which appear in the Upper Ludlow Rocks as the oldest of fishes, continue in at least one species to exist still. It would almost seem as if some such law influenced the destiny of genera in this ichthyic class, as that which we find so often exemplified in our species. The dwarf, or giant, or deformed person, is seldom a long liver;—all the more remarkable instances of longevity have been furnished by individuals cast in the ordinary mould and proportions of the species. Not a few of these primordial ganoids wore, however, of the highest rank and standing ever exemplified by their class; and we find Agassiz boldly assigning a reason for their superiority to their successors, important for the fact which it embodies, and worthy, as coming from him, of our most respectful attention. "It is plain," we find him saying, "that before the class of reptiles was introduced upon our globe, the fishes, being then the only representatives of the type of vertebrata, were invested with the characters of a higher order, embodying, as it were, a prospective view of a higher development in another class, which was introduced as a distinct type only at a later period; and from that time the reptilian character, which had been so prominent in the oldest fishes, was gradually reduced, till in more recent periods, and in the present creation, the fishes lost all this herpetological relationship, and were at last endowed with characters which contrast as much, when compared with those of reptiles, as they agreed closely in the beginning. Lepidosteus alone reminds us in our time of these old-fashioned characters of the class of fishes as it was in former days."



The ancient fishes seem to have received their fullest development during the Carboniferous period. Their number was very great: some of them attained to an enormous size, and, though the true reptile had already appeared, they continued to retain, till the close of the system, the high reptilian character and organization. Nothing, however, so impresses the observer as the formidable character of the offensive weapons with which they were furnished, and the amazing strength of their defensive armature. I need scarce say, that the Palaeontologist finds no trace in nature of that golden age of the world, of which the poets delighted to sing, when all creatures lived together in unbroken peace, and war and bloodshed were unknown. Ever since animal life began upon our planet, there existed, in all the departments of being, carnivorous classes, who could not live but by the death of their neighbors, and who were armed, in consequence, for their destruction, like the butcher with his axe and knife, and the angler with his hook and spear. But there were certain periods in the history of the past, during which these weapons assumed a more formidable aspect than at others; and never were they more formidable than in the times of the Coal Measures. The teeth of the Rhizodus—a ganoidal fish of our coal fields—were more sharp and trenchant than those of the crocodile of the Nile, and in the larger specimens fully four times the bulk and size of the teeth of the hugest reptile of this species that now lives. The dorsal spine of its contemporary, the Gyracanthus, a great placoid, much exceeded in size that of any existing fish: it was a mighty spear head, ornately carved like that of a New Zealand chief, but in a style that, when he first saw a specimen in my collection, greatly excited the admiration of Mr. Ruskin. But one of the most remarkable weapons of the period was the sting of the Pleuracanthus, another great placoid of the age of gigantic fishes. It was sharp and polished as a stiletto, but, from its rounded form and dense structure, of great strength; and along two of its sides, from the taper point to within a few inches of the base, there ran a thickly-set row of barbs, hooked downwards, like the thorns that bristle on the young shoots of the wild rose, and which must have rendered it a weapon not merely of destruction, but also of torture. The defensive armor of the period, especially that of its ganoids, seems to have been us remarkable for its powers of resistance as the offensive must have been for their potency in the assault; and it seems probable that in the great strength of the bony and enamelled armature of this order of fishes we have the secret of the extremely formidable character of the teeth, spines, and stings that coexisted along with it.



Such of the fishes of the present time as live on crustacea and the shelled molluscs,—such as the Wrasse or rock-fish family, and at least one of the Goby family, the sea-wolf,—have an apparatus of crushing teeth greatly more solid and strong than the teeth of such of their contemporaries as are either herbivorous or feed on the weaker families of their own class. A similar remark applies to the ancient sharks, as contrasted with those of later times. So long as the strongly-armed ganoidal order prevailed in nature, the sharks were furnished with massive crushing teeth; but when the ganoids waned in creation, and the soft-scaled cycloid and ctenoid orders took and amply filled the place which they had left vacant, the well known modern form of sharks' teeth was introduced,—a form much rather suited for cutting soft bodies than for crushing hard ones. In fine, the offensive weapons of the times of the Coal Measures seem very formidable, just as those personal weapons of the middle ages seem so that were borne at a time when every soldier took the field cased in armor of proof. The slim scimitar or slender rapier would have availed but little against massive iron helmets or mail coats of tempered steel. And so the warriors of the period armed themselves with ponderous maces, battle-axes as massive as hammers, and double-handed swords of great weight and strength.

Before passing onwards to other and higher classes and orders, as they occurred in creation, permit me to make the formidable armor of the earlier fishes, offensive and defensive, the subject of a single remark. We are told by Goethe, in his autobiography, that he had attained his sixth year when the terrible earthquake at Lisbon took place,—"an event," he says, "which greatly disturbed" his "peace of mind for the first time." He could not reconcile a catastrophe so suddenly destructive to thousands, with the ideas which he had already formed for himself of a Providence all-powerful and all-benevolent. But he afterwards learned, he tells us, to recognize in such events the "God of the Old Testament." I know not in what spirit the remark was made; but this I know, that it is the God of the Old Testament whom we see exhibited in all nature and all providence; and that it is at once wisdom and duty in his rational creatures, however darkly they may perceive or imperfectly they may comprehend, to hold in implicit faith that the Adorable Monarch of all the past and of all the future is a King who "can do no wrong." This early exhibition of tooth, and spine, and sting,—of weapons constructed alike to cut and to pierce,—to unite two of the most indispensable requirements of the modern armorer,—a keen edge to a strong back,—nay, stranger still, the examples furnished in this primeval time, of weapons formed not only to kill, but also to torture,—must be altogether at variance with the preconceived opinions of those who hold that until man appeared in creation, and darkened its sympathetic face with the stain of moral guilt, the reign of violence and outrage did not begin, and that there was no death among the inferior creatures, and no suffering. But preconceived opinion, whether it hold fast, with Lactantius and the old Schoolmen, to the belief that there can be no antipodes, or assert, with Caccini and Bellarmine, that our globe hangs lazily in the midst of the heavens, while the sun moves round it, must yield ultimately to scientific truth. And it is a truth as certain as the existence of a southern hemisphere, or the motion of the earth round both its own axis and the great solar centre, that, untold ages ere man had sinned or suffered, the animal creation exhibited exactly its present state of war,—that the strong, armed with formidable weapons, exquisitely constructed to kill, preyed upon the weak; and that the weak, sheathed, many of them, in defensive armor equally admirable in its mechanism, and ever increasing and multiplying upon the earth far beyond the requirements of the mere maintenance of their races, were enabled to escape, as species, the assaults of the tyrant tribes, and to exist unthinned for unreckoned ages. It has been weakly and impiously urged,—as if it were merely with the geologist that men had to settle this matter,—that such an economy of warfare and suffering,—of warring and of being warred upon,—would be, in the words of the infant Goethe, unworthy of an all-powerful and all-benevolent Providence, and in effect a libel on his government and character. But that grave charge we leave the objectors to settle with the great Creator himself. Be it theirs, not ours, according to the poet, to

"Snatch from his hand the balance and the rod, Rejudge his justice, be the god of God."

Be it enough for the geologist rightly to interpret the record of creation,—to declare the truth as he finds it,—to demonstrate, from evidence no clear intellect ever yet resisted, that he, the Creator, from whom even the young lions seek their food, and who giveth to all the beasts, great and small, their meat in due season, ever wrought as he now works in his animal kingdom,—that he gave to the primeval fishes their spines and their stings,—to the primeval reptiles their trenchant teeth and their strong armor of bone,—to the primeval mammals their great tusks and their sharp claws,—that he of old divided all his creatures, as now, into animals of prey and the animals preyed upon,—that from the beginning of things he inseparably established among his non-responsible existences the twin laws of generation and of death,—nay, further, passing from the established truths of Geologic to one of the best established truths of Theologic science,—God's eternal justice and truth,—let us assert, that in the Divine government the matter of fact always determines the question of right, and that whatever has been done by him who rendereth no account to man of his matters, he had in all ages, and in all places, an unchallengeable right to do.

The oldest known reptiles appear just a little before the close of the Old Red Sandstone, just as the oldest known fishes appeared just a little before the close of the Silurian System. What seems to be the Upper Old Red of our own country, though there still hangs a shade of doubt on the subject, has furnished the remains of a small reptile, equally akin, it would appear, to the lizards and the batrachians; and what seems to be the Upper Old Red of the United States has exhibited the foot-tracks of a larger animal of the same class, which not a little resemble those which would be impressed on recent sand or clay by the alligator of the Mississippi, did not the alligator of the Mississippi efface its own footprints (a consequence of the shortness of its legs) by the trail of its abdomen. In the Coal Measures, the reptiles hitherto found,—and it is still little more than ten years since the first was detected,—are all allied, though not without a cross of the higher crocodilian or lacertian nature, to the batrachian order,—that lowest order of the reptiles to which the frogs, newts, and salamanders belong. These reptiles of the carboniferous era, though only a few twelvemonths ago we little suspected the fact, seem to have been not very rare in our own neighborhood. My attention was called some time since by Mr. Henry Cadell,—an intelligent practical geologist,—to certain appearances in one of the Duke of Buccleuch's coal pits near Dalkeith, which lie regarded as the tracks of air-breathing quadrupeds; and, after examining a specimen, containing four footprints, which he had brought above ground, and which not a little excited my curiosity, we visited the pit together. And there, in a side working about half a mile from the pit mouth, and about four hundred feet under the surface, I found the roof of the coal, which rose at a high angle, traversed by so many foot-tracks, upwards, downwards, and athwart, that it cost