without (excepting in the case of the higher Cryptogamia) being permitted to enjoy any of the parental care which flowering plants exercise over their infant germs. From the scavengers of Nature we pass on now to her bond-slaves, the lichens. To show in what degree they merit the title, we may quote the following passage from Dr. Carpenter's Vegetable Physiology, a work from which we have already drawn. The mode in which lichens prepare the sterile rock for the reception of plants that require a higher kind of nourishment, is most remarkable. They may be said to dig for themselves graves for the reception of their remains when death or decay would otherwise speedily dissipate them. For whilst living, these lichens form a considerable quantity of oxalic acid, and this acts chemically on the rock, especially if of limestone, forming a hollow which retains the particles of the structure when the term of connected existence has expired. The moisture which is caught in these hollows finds its way into the crevices and cracks of the rocks, and when frozen rends them into minute fragments by its expansion, and thus adds more and more to the forming soil. Successive generations of these bond-slaves continually and indefatigably perform their duties, until at length, as the result of their accumulated toil, the barren and insulated rocks, or the pumice and lava of the volcano, become converted into fruitful fields. For where Flora's standard has once been planted on tracts thus claimed, they are soon colonized by plants of other tribes. The mosses, ferns, and other Cryptogamia follow them; and at length, by the growth and decay of successive generations of plants, a sufficient thickness of soil is produced for the nourishment of the luxuriant herbage and the support of the lofty forest-tree. Unlike the fungi, which spring into existence, propagate their kind, and decay, often within the limits of a few hours, the lichens are exceedingly slow in growth, live very long, some of them having been known to attain to the age of at least a thousand years, during the space of which they change but little in aspect, and are scarcely altered by decay or death. Similar to their inertness as regards growth, is their want of energy in their reproductive powers. They multiply themselves by small buds, looking like fine green dust to the naked eye, and contained in hollows formed on their surface. These hollows are termed shields, and whenever they begin to develop themselves, the lichen which produces them changes in appearance to such an extent as scarcely to be known for its former self. Like their near relatives, the mosses and fungi, each different tribe has its own favourite haunt: some, loving the light, flourish only where the aspect is south; others, again, hide from the rays of the sun, in dark nooks on the northern side of old walls or the trunks of trees. Some court the rising, others the setting sun; some flourish best on sterile cliffs, where but little moisture can reach them; others frequent rocks dripping with water. Some haunt the stately fir-tree, and from its branches hang their grey streamers; others prefer to cling to the gnarled boughs of the oak, or to spread their hoary crusts over the bark of the elegant birch, while others again delight to adorn with their shaggy beards the apple-trees of an old orchard. The lime and weather stains, as they are called, the rich colouring of which we so often admire on the face of seaside cliffs, are owing to the presence of tribes of this same family. Everywhere they abound, caring not much more for the cold of the Poles than the heat of the Tropics; as much at home on the highest elevations of the Andes and the Himalayas as in the warm and sheltered valleys of southern England; but though they brave the extremes of heat and cold, they flourish most luxuriantly in tropical regions, and where they are not exposed either to excess of drought or moisture. Clinging to life with the greatest tenacity, they may seem to be completely destroyed by drought, but their vitality is immediately restored by the administration of a dose of water. If our limits permitted, we should have much to say on the structure of lichens, as well as on their uses, the important character of their products, and many other interesting particulars connected with them. As it is, we can only give a passing mention to one or two of the most interesting species. Of such is the tripe de roche, which, forbidding in appearance and nauseous in taste though it be, has often preserved the lives of Arctic travellers. Then there is the reindeer moss, fed on which cattle are said to produce delicious milk and butter; and the Iceland moss, which the Icelanders use not only as food for themselves, but as fodder for their cattle. Many species of lichens were formerly said to possess medicinal properties. One kind is employed by certain Siberian monks for flavouring their beer; another was at one time much used in Egypt for imparting a highly-approved flavour to bread. The 'orchella weeds' of commerce are a species of lichen which are very widely diffused; their property of yielding a purple dye by maceration being accidentally discovered by a Florentine merchant. Besides these there are many other dye-lichens, as for instance the Cornicularia vulpina, used in Norway and Sweden to dye worsted stuffs, and believed, in the latter country, to be poisonous to wolves. But we must not linger any longer among this interesting family; therefore, trusting our readers will thank us for introducing them to their acquaintance, we take our leave, and ascending another step in the scale, find ourselves in presence of the mosses, nature's tiny workmen, so called from the office these delicate little beings perform in preparing a virgin soil for the reception of other plants. No spot is too desolate, none too sterile, for mosses to inhabit and enliven. From Spitzbergen to the islands of the Antartic Ocean, along the sides of lofty mountains, in the most exposed situations, couching on wild heaths, overspreading old walls, nestling in hedges, clinging to the bark of trees, loving much and equally frost and snow, wind and tempest, needing nothing but moisture for their sustenance,-everywhere they may be seen, adding fresh beauty to even the loveliest spots, making gay the solitary places of the earth, and causing the arid desert to rejoice and be glad. Not only are they the first plants which, as by a miracle, make their appear 349 ance in a newly-formed soil, but, with fond tenacity, they cling to the spot where they have once taken root, long after all other plants have deserted it, and, tender in their nature, delicate in structure though they be, show wonderful power in resisting influences which are generally fatal to the vegetable creation. In this respect close akin to the lichens, they may appear to be destroyed by drought; but no sooner does the generous rain descend upon them, than suddenly they are invested with new life, and their leaflets reappear as fresh, as luxu riant as ever. In using the word leaflets, it must not be supposed that there is any resemblance between them and leaves properly so called, devoid as the former are of both stomata and a woody skeleton. There is also this further peculiarity about them, that from their under surface root-fibres are often struck outthese simple plants, as is the case with the lower animals, not being provided with a set of organs each specially set apart for the performance of one function only. Thus the higher we rise in the scale of the vegetable creation, as well as in that of the animal world, the more complex becomes the whole structure, and the less complicated the functions each several organ has to perform. But while the moss leaflets are concerned in the production of root-fibres, they have nothing to do with the fructification, which is contained in a tiny urn of elegant shape, a beautiful fringe being set round its edge. This urn is mounted on the summit of a slender stalk, and is furnished with a lightlyfitting lid. Within it are contained the spores, which are affixed to a pillar rising in the centre. So soon as these spores have arrived at maturity, the lid covering this exquisitely-shaped little urn falls off, and the spores are sent flying out of it by means of a set of elastic spirallyformed filaments, which until that moment had lain coiled up and inactive. After the spores have fallen into the soil, their outer coats rupture, and a number of little tubes make their appearance. These tubes are full of granules; but although every one of them has the property of forming a separate plant, they are content to unite their efforts and bring forth a single moss. From one end of the granules, threadlike roots strike into the ground in the process of germination, and from the other proceed obtuse projections of a light-green colour, which in the course of a few days put forth a number of branches, in appearance exactly resembling the filamentous branches of the conferva. In this state the moss remains some weeks, sometimes even months, the time varying in different species, and then the true leaves make their appear ance. We have hitherto had to do with nature's lowliest servants and humblest slaves, insignificant in their appearance, yet wonderful in their works, and beautiful, too, if Interchange of service is the law and condition of beauty, Any way beautiful only to be the thing one is meant for. Now we may turn to the aristocracy of their race, the beautiful and graceful ferns, whose mission on earth seems only to be that they should live and be lovely.' A noble aristocracy, too, they are, possessing a genealogical tree whose roots strike deep into the foundations of an earlier creation, when they held a distinguished place among the families which flourished and covered the earth while it was yet young and untenanted of man. Constituting, as their remains do, a large portion of the fossil flora of our world, they may be regarded as a sort of Rosetta stone, the deciphering of which has enabled us to unlock many of the secrets respecting the past conditions of the earth, which otherwise would have remained concealed. From the myriads of specimens which have left their signatures in the coal measures and shales whose seams intersect all the countries of the world, it would seem that in those days the race was as cosmopolitan as it is now; that groves of bracken and forests of those magnificent tree-ferns which, since the historical period commenced, are to be found only in tropical regions, then spread a vegetation varied and rich over hill and valley, moorland and plain. Amongst those which flourish among us now, the most elegant and graceful of them all is a variety which grows in New Zealand, and from whose trunk or stem, twelve feet in height, depend fronds often eighteen feet long. Many of the species frequently reach a height of fifty feet, and with their graceful crown of feathery fronds, delicately cut, and waving with the slightest breath of air, they form exceedingly beautiful and noble objects. Even in our own country, nothing gives such a tropical character to the landscape as the common bracken, when, attaining a height of some eight or ten feet, it springs up under the shelter of forest trees, or in the hedgerows, dwarfs all the plants amidst which it rises with its widely-spreading fronds. It is in tropical islands, however, where they enjoy an abundant supply of both warmth and luxuriantly: but they shrink from moisture, that ferns grow most the heat of torrid continents, and while the burning plains of Africa are destitute of their presence, they delight in the temperate regions of Great Britain, and even in the colder climates of the North of Europe and America. It appears also that ferns bear a larger proportion to flowering plants towards maximum, and towards the Poles, the Equator, where they reach their where they attain their minimum, than they do in the Temperate Zones, their proportional number sinking lowest towards the middle of the Temperate Zone, while in England the proportion between ferns and flowering plants is as one to thirty-five. The Polypodiacea is of all the various species one of the most widely distributed. It especially abounds in our islands, living a contented life in situations the bleakest and most barren, venturing very near the sea coast, and wandering along the declivities of our highest hills, though best loving the warm and humid valleys of our south-western coasts, and but seldom showing itself on lands and downs, where there is nothing to shade it from the defend it from the wind. There is but one species of fern, the glistening Asplenium ma sun or moor rinum, which, as its name indicates, delights to taste the sea spray and to have its fronds wetted by the salt waves; but there are many which are hardy enough to flourish in the most exposed and arid situations. A soil composed of decaying vegetable matter is what they most affect: some species grow amongst the moss which clothes the branches of trees; others, again, take root in the crevices of old walls, adorning them with verdant cornices, and bestowing upon them a grace beyond the reach of art. Many species luxuriate in hedgerows; some grow beneath the shade of trees which overhang a stream; some on the mossy rocks in the bed of a waterfall, their leaves glistening and trembling in the perpetual spray. The Osmunda regalis, aptly named royal fern, as being the noblest and most majestic-looking of our British ferns, prevails chiefly in the south-west of England, where it grows in great luxuriance, thriving in marshy situations, and beneath the shade of trees. It has a most stately aspect; its average height being three or four feet, though in favourable situations it is sometimes eight or ten feet high. Its fronds are leafy in the lower part and fertile at the top, where the contracted apex, of a rich brown colour, looks like a cluster of flowers surmounting the stem. Very different in appearance from this kingly plant is the delicate shield fern (Aspidium oreopteris), which has the pleasant peculiarity of emitting an aromatic perfume when the frond is gently rubbed or drawn through the hand. If however the situation be not quite to the taste of this fastidious plant, or cold weather try its sensitive temper, the formation of the pores from which the perfume proceeds does not take place. Not only is there an Osmunda regalis, a monarch of ferns, but they also possess a type of manly strength and vigour in the male fern (Aspidium felix mas.), which is remarkable not only for its robustness of appearance, but for a constancy and decision of character in which many of the family are wanting. As a fitting pendant to the male fern comes the lady fern (Athyrium felix femina), graceful in growth, 351 delicate in colour, elegant in form; and woman-like, exceedingly variable in its conditions, withering so soon as it is gathered, and perishing beneath the first chilling touch of the unkindly autumn frosts. In warm, moist, and sheltered situations it grows abundantly, both in Great Britain and Ireland; and it is also widely distributed over Europe, Asia, Africa, and America. By some botanists the common bracken has been designated the female fern, from the graceful feathering of its fronds; but the lady fern certainly excels it in beauty of form and delicacy of texture. Flourishing as the bracken does in all kinds of soil and any situation, it has a decided distaste for culture, and in disposition is so exceedingly indolent that it remains in a torpid state a good eight months of the year; and, like the lady fern, is apt to be cut off by the first frosty night. Fertile though it be, each frond producing millions upon millions of seeds, its offspring are scarcely ever seen; to which circumstance is most probably owing, as Mr. Francis observes in his Analysis of British Ferns, the notion entertained by our ancestors, that it yielded no seeds, or that it was a rarity only to be procured at the exact moment in which John the Baptist was born. Happy was he who at that witching hour of the soft Midsummer night was fortunate enough to obtain some of the seed of this wondrous onenight seeding fern,' for by means of it the lucky possessor was enabled to render himself invisible when and where he pleased. Nor was this the only quality supposed in the good old days to pertain to the bracken; it was also considered, in accordance with the doctrine of antipathies and affinities, to be an excellent specific for reed- i. e., punctured wounds-because it was asserted that the fern died if the reed was planted about it; and vice versa, that the reed died if it were compassed about with fern. These were its fancied virtues, but it has real uses too. Living, it is a favourite haunt of deer; and withered, it is not only valuable as fodder for cattle, thatch for cottages, and fuel for ovens, but containing, as it does, a large proportion of tannin, it is excellently well adapted for the preparation of certain kinds of leather. There is yet another peculiarity about it, with which we must all of us have been familiar, when in our boyhood we tore up the plant by the roots and cut the leaf-stalk transversely, for the purpose of seeing in the arrangement of the vessels contained in it the image of King Charles' oak. To Erasmus' imagination, however, it appeared as a spread eagle, and as such it is spoken of in a curious book the production of Desiderius Erasmus. The difference in the images is, we suspect, owing to the manner in which the stalk is cut. We have devoted so much space to the biography of the bracken, that we must pass quickly by the other species which we had intended to notice-such as the mountainparsley, brightening with its verdure grey rocks; the lovely maidenhair, which forms so elegant an adjunct of a lady's bouquet; the film ferns, smallest of all our native ferns, and nearly resembling mosses in their appearance; and the beautiful bristle fern, which thrives amidst dripping rocks, and clothes with its luxuriant verdure their smooth ledges. Lastly, there is the anomalous-looking and mysterious moonwort, with its magical virtues. Resembling the moon in the form of its leaves it is said that if those leaves be gathered by moonlight they will perform wonders, loosening iron bolts, making locks fly open, causing the halt to walk, and the sick to be restored to health. Alone of all the families of Cryptogamia, possessed of fully-developed leaves and of a vascular structure, though their stems contain no real wood, ferns are closely allied to flowering plants in these respects, while they differ from them widely as regards their organs of reproduction, and in several other respects. Some species are often several years in attaining to maturity, and in the progress of their development manifest many varying features. Thus, in the case of the great shield fern (Aspedinia dilatatum) when growing on a barren soil, where but little moisture can reach it, the leaf becomes small and less divided, the pinnules blunted and reflexed. Growing by a stream where, however, the water fails during summer, its fronds become large, drooping, and dark in colour, continued wet having a tendency to elongate them and widely separate the pinnules. The various appearances assumed by the bristle bladder fern are in its case determined by the nature of the season, and whether the temperature be cold or genial. Amongst the many interesting characteristics possessed by ferns, none is more so than the vernation or spiral rolling up of their as yet unexpanded fronds. The arrangement by which this is effected is most beautiful, each little segment being rolled up towards the rib which supports it, that rib in its turn being coiled up towards the midrib, and the midrib towards the footstalk. As the spring advances the coiled-up fronds take courage and begin gradually to unfold, the larger divisions shaking themselves out first, then the smaller ones following their example, until the whole frond is uncoiled, and under the influence of light and air becomes gradually brighter in hue. The reproduction of ferns had, until within the last few years, been a vexed question among botanists, the want of any visible flowers giving rise to many conflicting theories, which all fell wide of the truth, as they could not fail to do so long as the representatives of pistils and stamens were sought for in the perfect plant, and no idea of a process analogous to that by which a tadpole is developed into a frog had presented itself to the minds of those who were directing their attention to the subject. At last the riddle was solved by Count Sumenski, to whom belongs the merit of having discovered that it is in the structures developed from the spores in germination that the pistillidia and antheridia of ferns are to be sought. The nature of the phenomena by which the propagation of ferns is effected is as follows. In all the different species of ferns the spores are contained in brown dots on lines collected on the under surfaces, or along the edges of the fronds. Each of these spore-cases is surrounded by an elastic ring, which, |