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The most striking and predominant trees in these forests are, the graceful fern-trees, the Casuarinæ,
ravines, to scale the mountains, to cross the valleys, to force a passage through the virgin forests, which seem to exhale the inspiring atmosphere of the fresh created earth, - to survey there the riches of vegetation and the boundless munificence of nature, - to observe how each hill — each valley, varies in character - how each trunk, branch, leaf and flower has its own peculiar beauty of form and colour, — to examine and to contemplate all this, so strikes the mind with admira. tion of terrestrial wonders, as to cause it involuntarily to rebound towards its Creator. . . . . . . . .
It is more particularly in the forest that the grand and the picturesque, the sublime and the fantastic, form the most singular and happy combinations. From the loftiest giants of the forest, down to the humblest shrubs, all excite the astonishment of the spectator. By means of the parasites, which form the most characteristic feature of the Brazilian forests, every thing seems united in one community of being and of aim. These, at first creeping parasites, soon cling boldly and closely to the tree, climb it to a certain height, and then, letting their tops fall to earth, again take root there, - again shoot up, push from branch to branch, from tree to tree, in every direction, until — tangled, twisted, and knotted in every possible form—they festoon the whole forest with a drapery, in which a ground-work of the richest verdure is variegated with garlands of the most beautiful and many-coloured flowers. Sometimes the parasites choke the tree which they embrace : the latter then decays and falls, while the former remain suspended, attached to the surrounding trees, and constantly increasing in thickness, until they present the appearance of magnificent twisted columns, around which a fresh growth of plants soon rises, turning and clinging with a grace which is inde. scribable. In no other part of the world is nature so great a coquette as here. At every period in the life of plants, her desire to please and to fascinate appears immoderate and unlimited : all that is ugly, melancholy, or repulsive, all that speaks of gloom, decrepitude, or decay, -is banished: the breath of an eternal spring is maintained throughout the forest; and flowers and fruit, loading the same branch, are presented in constant succession, and in colours ever fresh. If a tree wither, or shed its leaves, or begin to show symptoms of decay, thousands upon thousands of plants climb it, and weave a robe with which to cover its infirm trunk and branches; and having fulfilled this mission, re-descend from the summit, playfully waving their plumes, sporting with and embracing millions of others, which they meet on the way, until at length they lose themselves in the immensity of the thicket. If the tree decays, if it falls overwhelmed with age; nature hastens to conceal the horrors of death. She summons the moss and the lichens to prepare it a bed — she calls forth a thousand parasites to form a pall or covering for the couch. Thus, instead of the uprooted and rotten trunks, which in our forests of North Europe exhibit scenes of naked desolation, we have here only so many gorgeous canopies, surmounting sofas velvetted with the rich and delicate plants which beautify the pines, the Van Diemen's Land sassafras (the Atherosperma of Labillardière), the myrtle, the Banksio, the Eucalypta, and Acacia.
Respecting the two latter, R. Brown observes, " that these two genera are not only the most widely diffused, but by far the most extensive, in Terra Australis, about one hundred of each having already been observed ; and, if taken together, and considered with respect to the mass of vegetable matter which they contain, calculated from the size as well as the number of individuals, are perhaps nearly equal to all the other plants of that continent. They agree very well also, though belonging to very different families, in a part of their economy, which contributes somewhat to the peculiar character of the Australian forests, — namely, in their leaves, or the parts performing the functions of leaves, being vertical, or presenting their margin, and not the surface, towards the stem, both surfaces having, consequently, the same relation to light.
“ This economy, which uniformly takes place in the Acaciæ, is in them the consequence of the vertical dilatation of the foliaceous petiole; while in Eucalyptus, where, though very general, it is by no means universal, it proceeds from the twisting of the footstalk of the leaf.
“ These two genera still more uniformly agree in the similarity of the opposite surfaces of their leaves. But this similarity is the indication of a more important fact, namely, the existence equally on both surfaces of the leaf of those organs which by most
forest. If examined more closely, if this exquisite carpet be raised, a new world reveals itself; millions of worms, and millions of young plants, are springing from the bed of death, and astonish the eye. Every thing submits here, as elsewhere, to the law of nature ; but here only nature conceals all the hideous processes of decomposition, and so embellishes the very shroud of death that it appears to the eye but as the graceful drapery of some festal scene. — MS. Journal of the Author,
authors are denominated pores, or stomata of the epidermis."*
Independent of the described vegetation, the Australian continent, so far as it has yet been brought to light, possessed a flora which differs materially from what we know in the present day of the existing Australian plants, and which lays strong claims to priority of investigation.
These specimens of fossil plants, collected by myself, which arrived without damage in England, are but few: they may be referred to two distinct geological epochs ; first, that of the deposition of coal, and the sandstone superincumbent on the coal, of the Jerusalem Basin ; and, secondly, that of the formation of the (tertiary) yellow limestone at Hobart Town, which contains impressions of leaves of an unknown vegetation, and a Helix and Bulimus not as yet identified with any existing forms.
J. Morris, Esq., author of the Catalogue of British Fossils, to whom natural history is greatly indebted for his zeal in the promotion of palæontological researches, has kindly undertaken the examination of my Australian specimens, the result of which is now submitted to the reader, in his own words.
“ CARBONIFEROUS FLORA.
“ SPHENOPTERIS Brongniart. “ There is one species of this genus, belonging to the section of which S. linearis, S. elegans, and S. trichomanoïdes are the type; but differing generally from all of them, as regards the arrangement of the pinnulæ. It may be thus briefly characterised :
* “ Sketch of the Botany of the Vicinity of Swan River," by R. Brown, Esq., F.R.S.; Journal of the Royal Geographical Society, 1830–31., p. 17.
“Frond, furcate, slender; pinnulæ, cuneiform, tri. lobed, truncate at the apex, and rather distant from each other.
“I have not ventured to give a name or a figure of this species, having only seen a drawing taken by the author of this volume from a specimen in possession of William Breton, Esq., of Launceston, Van Diemen's Land, which exhibits the above characters, but in which the venation is not defined.”
Locality.–Jerusalem basin, Van Diemen's Land.
Sphenopteris lobifolia. (Pl. VII. fig. 3. 3a.) “Frond bipinnate; pinnæ, somewhat linear, elongate, alternate; pinnulæ membranous, those of the lower pinnæ equal, ovate oblong, contracted at the base, approximate, with three nearly equal rounded lobes on each side, and a terminal obtuse one; the veins, proceeding into each lobe, divide near the mid rib, the upper one being furcate; the pinnulæ towards the apex of the frond are rather sharply three-lobed and decurrent, the veins becoming furcate in each lobe.
“ This appears to have been a very delicate fern: the pinnulæ are very slender, or membranous, and variable in shape according to their position on the frond.”
Locality.-- Newcastle coal mines, New South Wales.
Sphenopteris alata var. exilis. (Pl. VII. fig. 4, 4a.) Syn. Pecopteris alata Brong. Hist. Veg. Foss.i. p. 361.
Aspidites alatus Göppert, Foss. Farn. p. 358. “ Frond somewhat triangular, with a tripinnatifid base; margin of the rachis alate; pinnulæ either contracted at the base or confluent, decurrent, irregularly lobed, lobes entire or dentate ; veins slender, pinnate.
“ This interesting species of fossil fern appears more
nearly related to Sphenopteris than Pecopteris, and is easily distinguished by the slender and decurrent pinnula and the membranous or alate margin of the principal rachis, as is observed in the recent species of Hymenophyllum.
“ Associated with the last species and Glossopteris Browniana in a light-coloured shale, from Hawkesbury River, New Holland. The museum of the Geological Society contains specimens of the two above-described species.”
Locality. — Newcastle basin.
Glossopteris Browniana (Pl. VI., fig. 1. 1a.) Brong.
Prod., p. 54. ; Veg. Foss., p. 223. t. 62. “Frond simple, spathulate or oblong-lanceolate, entire, attenuate at the base; midrib thick, canaliculate, gradually contracting towards the apex; veins oblique, anastomosing.
“ This beautiful specimen of fossil fern appears to be tolerably abundant in the carboniferous deposits of New Holland; and if these beds are of the age of the true coal-measures, it is the more interesting; for, in the northern coal-fields of Europe and America, we have no evidence of the existence of simple fronded ferns with reticulate venation. This species constitutes the type of Brongniart's genus Glossopteris, two other species are also referred to this genus, from the oolitic series of Sweden and England; the G. Phillipsii from the latter locality, agreeing precisely in its mode of venation with G. Browniana, appears, however, not to have been a simple frond, as originally described by Brongniart, but digitate, four or five pinnulæ arising in a flabellate form from a common rachis; in consequence of which, Göppert has arranged it under one of the sections of his genus Acrostichites.
“ The young or smaller pinnulæ of this fern are generally lanceolate, the larger ones are more spa