Robert Brown

“ In comparing together the Floras of Terra Australis and Europe, I shall chiefly confine myself to an enumeration of the species common to both countries; the subject at present hardly admitting of many remarks of a more general nature. It may, however, be observed, that none of the great natural orders of Europe are absolutely wanting in Terra Australis; that some of them, as Compositæ, Leguminosæ, Gramineæ and Cyperaceæ, are found even in nearly the same proportion; while others, as Cruciferæ, Ranunculaceæ, Caryophylleæ, Rosaceæ, and Ericeæ are reduced to very few species ”

“ It is impossible to say what branches of science will be most advanced by the researches of the expedition. Oftentimes discoveries are made when least expected. One discovery leads to another, and with the material at hand an accomplished naturalist can never fail to make interesting observations, and even deduce important generalizations which those at home, only acquainted with what has already been done, cannot even presage. ”

“ In these, the nucleus of the seed is not properly a monocotyledonous embryo, but has an appearance and economy more nearly resembling those of the tuber of a root; for, instead of being distinguishable into a cotyledon, a plumula and radicula, and of germinating in a determinate manner and from a single point, it is composed of a mass whose internal structure is uniform, and on the surface of which frequently more than one germinating point is observable. ”

“ I may remark here, that from the very limited extent of the collections of plants above enumerated, as well as from what we know of the north coast of New Holland, and I believe I may add of the Flora of India, it would seem that the comparative number of species in equal areas within the tropics and in the lower latitudes beyond them, has not been correctly estimated; and that the great superiority of the intratropical ratio given by Baron Humboldt, deduced probably from his own observations in America, can hardly be extended to other equinoctial countries. ”

“ Nowadays naturalists are not so particular about having a long list of new animals, or rare species. They are more anxious about the range of particular forms of interest, about questions of structure, and other particulars bearing on the philosophical questions of the day. These points can frequently only be made out by dissections on the spot. The large animals will afford plenty of material to the scalpel of the anatomist. What would a home-staying anatomist give, even to dissect on an ice-floe, a narwhal, or a white whale in a fresh or in any condition. ”

“ In the instances of naked seeds now given, the bursting of the pericarpium precedes the distinct formation of the embryo, while the proper coats of the seed remain entire till after its separation from the parent plant, and germination has commenced.
It may not be uninteresting to contrast this economy with that of the Mangroves and other plants of tropical countries, which grow on the shores, and within the influence of the tide. In many of these the embryo, long before the seed loses its original attachment, acquires a very considerable size ”

“ Cephalotus has been referred by its discoverer Labillardière to Rosaceæ, to which, notwithstanding its coloured calyx and the absence of petals, it seems to have the nearest aftinity; a knowledge of the fruit, however, is wanting to determine absolutely its place in the natural method. From the structure of its ovulum, even in the unimpregnated state, I entertain no doubt that the radicule of the embryo points to the umbilicus of the seed and therefore downwards ”

“ In zoology we must not expect too much. The researches of the expedition will be made in a very high northern latitude, where animal life is scarce. Perhaps the very scarcity of it makes the species which live there more interesting. The extreme northern range of animal or vegetable life is always valuable to know; and accordingly every specimen, more especially of the land fauna, will be an important acquisition to science. ”

“ It is still uncertain whether its reniform seed is destitute of albumen; the absence of which, however, does not seem necessary to establish its affinity with the other genera of this order; for plants having the same remarkable economy in the germination of the embryo as that of Rhizophora, may belong to families which either have or are destitute of albumen.
The plant referred to from Congo may be considered as a new species of Legnotis having its petals less divided than those of the original species of that genus, and each cell of its ovarium containing only two pendulous ovula. ”

“ Fabricius, no doubt, described it under the name of yak (Bos grunniens) as a member of the Greenland fauna, but all he saw was a skull drifted in the ice from the high North. The gradual discoveries of Kane, Hayes, and lastly of Hall, have shown that in the very highest reaches of Smith's Sound it is quite abundant, though entirely unknown south of the glaciers of Melville Bay. Almost contemporaneous with this discovery was that of the German expedition to East Greenland, that in a high-latitude it was abundant on that coast, though quite unknown further to the south. ”

“ The inner membrane of the ovulum, however, in general appears to be of greater importance as connected with fecundation, than as affording protection to the nucleus at a more advanced period. For in many cases, before impregnation, its perforated apex projects beyond the aperture of the testa, and in some plants puts on the appearance of an obtuse, or even dilated stigma; while in the ripe seed it is often either entirely obliterated, or exists only as a thin film, which might readily be mistaken for the epidermis of a third membrane then frequently observable. ”

“ In plants, either dried or immersed in spirit for a few days only, the particles of pollen of both kinds were found in motion equally evident with that observed in the living plant; specimens of several plants, some of which had been dried and preserved in an herbarium for upwards of twenty years, and others not less than a century, still exhibited the molecules or smaller spherical particles in considerable numbers, and in evident motion, along with a few of the larger particles, whose motions were much less manifest, and in some cases not observable. ”

“ If they are qualified — as doubtless they are — for the duties, then they may be safely left to do what they can. If they are not qualified, then for the credit of English science they had better be left at home. No one, however, who knows the stuff out of which the expedition is composed, will ever hesitate in believing that — though such an expedition is to a great extent at the beck of the ice, and a hundred other circumstances which those who have never sailed the ice-choked seas of the North can have little conception of — every man will do his best ”

“ It may also be remarked, that in those genera in which the Ascidia have an operculum, namely Nepenthes, Cephalotus, and Sarracenia, they exist in every known species of each genus, and the structure of these genera is so peculiar that they form three distinct natural families; while in Dischidia, whose pitchers are formed without opercula, these organs are neither found in every species of the genus, nor in any other genus of the extensive natural order to which it belongs. ”

“ I may remark, however, that in its scalariform vessels it agrees with all the fossil genera supposed to be Acotyledonous. In the structure of its sporangia and sporules it approaches most nearly, among recent tribes, to Lycopodiaceæ, and Ophioglosseæ; and among fossils, no doubt, to Lepidostrobus, and consequently to Lepidodendron.
The stem structure of Lepidodendron, known to me only in one species, Lepidodendron Harcourtii, offers no objection to this view, the vascular arrangement of the axis of its stem bearing a considerable resemblance to that of Triplosporite. ”

“ Caley has observed within the limits of the colony of Port Jackson nearly 50 species of Eucalyptus, most of which are distinguished, and have proper names applied to them, by the native inhabitants, who, from differences in the colour, texture and scaling of the bark, and in the ramification and general appearance of these trees, more readily distinguish them than botanists have as yet been able to do. Eucalyptus, although so generally spread over the whole of Terra Australis, and so abundant as to form at least four fifths of its forests, is hardly found beyond this country. ”

“ The Phænogamous plants of the list are, with very few exceptions, also natives of North America, and several of them are found even in other parts of the world.
There is nothing peculiar in the apparent structure or economy of the Dicotyledonous plants common to countries so remote to account for their more general diffusion; though several of them grow in wet or marshy ground, yet very few are properly aquatic plants; and in the structure of their seeds the only circumstance in which they all agree is in the plumula of their embryo not being evolved. ”

“ And I have some reason to believe, that the most extensive and valuable collection ever brought from the west coast of equinoctial Africa, namely, that formed by Professor Afzelius, during his residence of several years at Sierra Leone, does not exceed 1200 species; although that eminent naturalist, in the course of his researches, must have examined a much greater extent of country than was seen in the expedition to Congo. ”

“ The Herbarium formed by the late Professor Smith and his assistant, Mr. David Lockhart, on the banks of the Congo, was, on its arrival in England, placed at the disposal of Sir Joseph Banks; under whose inspection it has been arranged; the more remarkable species have been determined; and the whole collection has been so far examined as the very limited time which could be devoted to this object allowed.
In the following pages will be found the more general results only of this examination; descriptions of the new genera and species being reserved for a future publication. ”

“ And the ovarium, though in all cases of one cell, with a single ovulum, may, at least in those genera in which the style is divided, be supposed to unite in its substance the imperfect ovaria indicated by the branches of the style, and which in Buchanania are actually distinct from the complete organ. The only plant belonging to this order in the herbarium, is a species of Rhus, with simple verticillate leaves, and very nearly approaching in habit to two unpublished species of the genus from the Cape of Good Hope. ”

“ The increased development in the ovulum would not consist so much in the unusual form and thickening of the coat, a part of secondary importance, and whose nature is disputed, as in the state of the nucleus of the seed, respecting which there is no difference of opinion; and where the plurality of embryos, or at least the existence and regular arrangement of the cells in which they are formed, is the uniform structure in the family. ”

“ The character of Leptostomum, derived from the undivided annular process of the inner membrane of the capsule, may to many appear too minute, and perhaps unimportant; and had it been observed in one species alone, I should not have ventured on that account to distinguish it as a genus: but finding it in four species, accompanied too with a habit widely different from that of Gymnostomum, to which these plants must otherwise be referred, I have not hesitated to employ it. ”

“ The existence of spiral vessels, particularly in such quantity, and, as far as can be determined in the dried specimens, unaccompanied by other vessels, is a structure at least very unusual in the integuments of a seed or caryopsis, in which they are very seldom at all visible, and have never, I believe, been observed in such abundance as in this genus, in all whose species they are equally obvious. ”

“ Oxalis, indeed, differs from Averrhoa in the texture of its fruits, in some respects in the structure of its seed; and very widely in habit, in the greater part of its species. The difference in habit, however, is not so great in some species of Oxalis; as for example, in those with pinnated and even ternate leaves from equinoctial America; and in that natural division of the genus including O. sensitiva, of which there are two species in the Congo herbarium. ”

“ In other cases the albumen is formed by a deposition of granular matter in the cells of the nucleus. In some of these cases the membrane of the amnios seems to be persistent, forming even in the ripe seed a proper coat for the embryo, the original attachment of whose radicle to the apex of this coat may also continue. This, at least, seems to me the most probable explanation of the structure of true Nymphæaceae, namely, Nuphar, Nymphæa, Euryale, Hydropeltis, and Cabomba, notwithstanding their very remarkable germination, as observed and figured in Nymphæa and Nuphar by Tittmann. ”

“ RHAMNEÆ. Into this order I admit such genera only as have ovarium cohering more or less with the tube of the calyx, of which the laciniæ have a valvular æstivation; stamina equal in number to these laciniæ, and alternating with them; an ovarium with two or three cells and a single erect ovulum in each; an erect embryo generally placed in the axis of a fleshy albumen, or entirely without albumen; the petals, which are opposite to the stamina, and inclose the antheræ in their concave laminae, are in some cases wanting. ”