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piration of all who are interested in the ed- Göppart and Unger on the Continent, and ucation and moral wellbeing of their towns- by Dawson in Canada
- has received very
important accessions of late through the unMy remarks on the British Museum con- tiring energy of Mr. Binney, of Manchester, vey no reflection on the able officers who who has devoted nearly thirty years to the have in so short a time formed this wonder- search for those rarely-found specimens ful collection. The late Mr. Lawrence, in which exhibit the internal structure of the his lecture in 1815, congratulates his audi- plant. His elaborate description of the ence on the formation of a geological collec- most abundant and, till his researches, the tion having been just determined upon. In least-understood plant of the coal measures, 1838, when I first knew the Museum, in Old calamites, has just appeared in the memoirs Montague House, I was told it ranked of the Palæontographical Society; and about the sixth in Europe; now, and for some of Mr. Binney's materials having some years past, it has been considered to also formed the subject of a very recent and be the finest in the world. This is due to valuable paper by Mr. Carruthers, of the the energy and ability of the keepers and British Museum, I may quote their joint recurators; and, in mentioning them, I would sults as one. These show that calamites is wish to pay a passing tribute to the merits an actual member of the existing family of of the venerable Dr. Gray, who has de- Equisetaceæ which contained previously but voted his life to the development of the Ge- one genus — that of the common mare's-tails ological Department with a singleness of of our river-banks and woods; as also that purpose, liberality and zeal beyond all nearly a dozen other genera of coal-measure praise. At the time when Old Montague plants may be referred to it. This affinity House contained the national collections of calamites had, indeed, been guessed at there was but one museum in the metropo- before, and the genus now referred to it, lis in which the naturalist could study to having been founded on mere fragments, much purpose; this was the Hunterian (of were always doubtful; but the value of these the Royal College of Surgeons), then under positive identifications is none the less on the superintendence of the late Mr. Clift these accounts. It may hereafter prove of and of Prof. Owen, the friend of my early some significance that these calamites youth, when preparing myself to accompany which in the coal epoch assumed gigantic the Antarctic expedition, and who instructed proportions and presented multitudinous me in the use of that now unrivalled series forms and very varied organs of growth – of catalogues that owed so much to himself. are now represented by but one genus,
difFrom the Museum of the Royal College fering most remarkably from its prototype of Surgeons the national and provincial mu- in size and the simplicity and uniformity of seums of England have much to learn and its vegetable organs. to copy, and, thanks to the munificence of Passing to the tertiary times, the labours the Council of the college, and to the zeal of Count Saperte in France, of Gauden and and ability of the present conservator, Mr. Strozzi, and of Massolonghi in Italy, of Flower, it retains the position it attained Lesquereux in America, and, above all, of thirty years ago, of being the best and rich-Heer in Switzerland, have, within the last est institution of the kind in Europe. In ten years, accumulated vast numbers of my own special science the greatest advances species of fossil plants; and if the determithat have been made during the last ten nation of the affinities of the majority are years have been in the departments of Fos- trustworthy, they prove the persistence sil Botany and Vegetable Physiology. In throughout the tertiary strata of many inthe past history of the globe two epochs stand teresing families and genera, and the rarity prominently out — the carboniferous and i others than these. Here, however, much the miocene — for the abundant materiais value cannot be attached to negative evithey afford and the light they throw sh the dence. Almost the only available materials early conditions of the vegetable kingdom. for determining the affinities of the vast Why plants should have been so much more majority of these tertiary plants are their lavishly preserved during these than during mutilated leaves, and, unlike the bones of some of the intervening or earlier epochs vertebrate animals and the shells of molluses, we do not rightly know; but the compara- the leaves of individual plants are extremely tive poverty of the Floras of the latter is variable in all their characters. one among the strongest evidences of the im- Furthermore, the leaves of plants of difperfection of the geological record. Our ferent natural families and of different connknowledge of coal plants – which since the tries mimic one another to such a degree days of Sternberg, Brongniart, and Lindley that, in the case of recent flowers, every botand Hutton, has been chiefly advanced by anist regards these organs as a most treacherous guide to affinity. Of the structural that an arboreous vegetation once extended characters which are drawn from the inter- to the Pole itself. Discoveries such as these nal organs of plants, and especially from appear at first actually to retard the progtheir fruit, seeds and flowers, few traces are ress of science by confounding all previous to be found in the fossils, and yet it is from geological reasoning as to the climate and them exclusively that the position of a re- condition of the globe during the tertiary cent plant in the vegetable kingdom can be epoch. certified.
I have said that the greatest botanical An instructive instance of over-reliance discoveries made during the last ten years on leaves, and perhaps, too, on unperceived have been physiological, and I here alluded ideas, happened not long ago to a palæonto- especially to the series of papers on the ferlogist of such distinguished merit that his tilization of plants which we owe to Mr. reputation cannot suffer from an allusion to Darwin. You are aware that this distinit. In the course of his labours over some guished naturalist, after accumulating stores imperfect specimen from a most interesting of facts in geology and zoology during his locality, he referred these associated impres- circumnavigation of the globe with Capt. sions of fossil leaves to three genera, belong- FitzRoy, espoused the doctrine of the coning to as many different families of plants, tinuous evolution of life, and, by applying and was thus helped to what would have to it the principles of natural selection, been some important conclusions as to the evolved his theory of the origin of species. vegetation of the period in which they were Instead of publishing these views as soon deposited. A subsequent observer, who as conceived, he devoted twenty more years was a botanist, but not a palæontologist, to further observation, study, and experideclares these three supposed genera to be ment, with a view of maturing or subvertthe three leaflets of one leaf of one plant, ing them. Among the subjects requiring and this the common blackberry, which still elucidation or verification were many that grows on the spot. Which of the two is appertained to botany, but which had been right I do not say; the fact shows to what overlooked or misunderstood by botanical opposite conclusions different observers of writers, and these he set himself to examine the same fossil materials may be led. In vigorously. The first fruits of his labours this most unreliable of sciences, fossil bot- was his volume on the • Fertilization of any, we do but grope in the dark; of the Orchids,' undertaken to show that the same thousands of objects we stumble against we plant is never continuously fertilized by its here and there recognize a likeness to what own pollen, and that there are special prowe have elsewhere known, and rely on ex- visions to favour the crossing of individuals. ternal similitude for a helping hand to its As his study of the British species advanced, affinities. Of the great majority of speci- he became so interested in the number, mens we know nothing for certain, and of variety, and complexity of the contrivances no small proportion we are utterly ignorant. he met with, that he extended his survey to If, however, much is uncertain, all is not so, the whole family, and the result is a work of and the science bas of late made sure and which it is not too much to say that it has steady progress, and developed really grand thrown more light upon the structure and results. Meer's labours on the miocene and functions of the floral organs of this immense pliocene Floras, especially, are of the high- and anomalous family of plants than had est value and interest. His conclusions re- been shed by the labours of all previous garding the flower of the Bovey Tracy coal. botanical writers. It has, further, opened beds (for the publication of which in a form up entirely new fields of research, and disworthy of their value and of their author's covered new and important principles that merit we are indebted to the wise liberality apply to the whole vegetable kingdom. This of Miss Burdett Coutts) are founded on a was followed by his paper on the two wellsufficient number of absolute determinations: known forms of the primrose and cowslip and his more recent · Flora Fossils Arctica' (Journal of the Linnean Society of London, threatens to create a revolution in tertiary vi. p. 77), popularly known as the pin-eyed geology. In this latter work Prof. Heer and thrum-eyed; these forms he showed to shows, in apparently unassailable evidence, be sexual and complementary; their diverse that forests of Austrian, American and Asi- functions being to secure by their mutual atic trees flourished during miocene times action full fertilization, which he proved in Iceland, Greenland, Spitzbergen, and the could only take place through insect agency. Polar American Islands, in latitudes where In this paper he established the existence such trees could not now exist under any of homomorphic, or legitimate, and heteroconceivable conditions or positions of land morphic, or illegitimate, unions among or sea or ice, and leaving little doubt but plants, and details some curious observations in the structure of the pollen. The Darwin's on the fertilization of plants ; results of this, perhaps, more than any other some that appear to be commonplace at first of Mr. Darwin's papers, took botanists by sight are really the most subtle, and, like surprise, the plants being so familiar, their many other apparent commonplaces, are two forms of Hower so well known to every what, somehow, never occur to commonintelligent observer, and his explanation so place minds; as, for instance, that plants simple. For myself, I felt that my botani- with conspicuously-coloured flowers, or cal knowledge of these homely plants had powerful odours, or honeyed secretions, are been but little deeper than Peter Bell's, to fertilized by insects ; – all with inconspicuwhom
ous flowers, and especially such as have A primrose by the river's brim
pendulous anthers, or incoherent pollen, are A yellow primrose was to him,
fertilized by the wind; whence he infers And - it was nothing more.
that, before honey-feeding insects existed,
the vegetation of our globe could not have Analogous observation on the demor- been ornamented with right-coloured flowphism of flax flowers and their allies (Jour-ers, but consisted of such plants as pines, nal of the Linnean Society, vii. 69) formed oaks, grapes, nettles, &c. the subsequent paper, during which he The only other botanical paper of Mr. made the wonderful discovery that the com- Darwin's to which I can especially allude is mon flax, the pollen of one form of flower, that on the Habits and Movements of is absolutely impotent when applied to its Climbing Plants' (Journal of the Linnean own stigma, but invariably potent when ap- Society, vol. ix., p. 1), which is a most plied to the stigma of the other form of elaborate investigation into the structure, howers; and yet both pollens and stigmas modification and functions of the various of the two kinds are utterly undistinguish- organs by which plants climb, twine and atable under the highest powers of the mi- tach themselves to foreign objects. In this croscope. His third investigation is a very he reviews every family in the vegetable long and laborious one (Journal of the Lin- kingdom, and every organ used by any nean Society, viii. 169) on the common plant for the above purpose. The result loosestrife (Lythrum salicaria), which he places the whole subject in a totally new showed to be trimorphic; this one species ght before us.
The guesses, crude obserhaving three kinds of flowers, all annually. vations, and abortive experiments that had abundantly produced, and as different as if disfigured the writings of previous obserthey belonged to different species; each vers are swept away; organs, structures flower has, further, three kinds of stamen, and functions, of which botanists had no differing in form and function. We have previous knowledge, are revealed to them, in this plant, then, six kinds of pollen, of and the whole investigation is made as which five at least are essential to complete clear as it is interesting and instructive. fertility, and three distinct forms of style. The value of these discoveries, which add
To prove these various differences, and whole chapters to the principles of botany, that the co-adaptation of all these stamens is not theoretical only;, already the hortiand pistils was essential to complete fertil- culturist and agriculturist have begun to ity, Mr. Darwin had to institute 18 sets of ponder over them, and to recognize in the observations, each consisting of 12 experi- failure of certain crops the operation of ments, 216 in all. Of the labour, care, and laws that Mr. Darwin first laid down. delicacy required to guard such experiments What Faraday's discoveries are to teleagainst the possibility of error, those alone graphy Mr. Darwin's will assuredly prove can tell who know experimentally how diffi- to rural economy in its widest sense and cult it is to hybridize a large flowered plant most extended application. of simple form and structure. The result Another instance of successful experiin this case, and in those of a number of al- ment in Physiological Botany is Mr. Her lied plants experimented on at the same bert Spencer's observations on the circulatime, is what the author's sagacity predict- tion of the sap and formation of wood in ed; the rationale of the whole was demon- plants (Linnean Transactions, vol. xxv., p. strated, and he finally showed, not only how 405). Às is well known, the tissues of our nature might operate in bringing these com- herbs, shrubs and trees, from the tips of plicated modifications into harmonious oper- their roots to those of their petals and ations, but how through insect agency she pistils, are permeated by tubular vessels. does do this, and why she does it too. The functions of these have been hotly dis
It is impossible ever to enumerate the puted, some physiologists affirming that they many important generalizations that have convey air, others fluids, others gases, and flawed from these and other papers of Mr. I still others assigning to them far-fetched
uses of a wholly different nature. By a | You may say that these cells have inherited series of admirably contrived and conduct- the potentiality to do so; but this is not all, ed experiments Mr. Spencer has not only for every plant thus produced in like manshown that these vessels are charged at cer- ner developes on its stalks and leaves tain seasons of the year with fluid, but that myriads of similar cells, endowed with the they are intimately connected with the for- same property of becoming such in new mation of wood.' He further investigates plants; and so on, apparently interminably. the nature of the special tissues concerned Therefore the original cell that left the in this operation, and shows not merely grandparent, not only carried with it this how they may act, but to a great extent how so-called potentiality, but multiplied it and they do act. As this paper will, I believe, distributed it with undiminished power be especially alluded to by the President of through the other cells of the plant itself the Biological Section, I need dwell no fur- produced; and so on, for countless generther on it here than to quote it as an ex- ations. What is this potentiality, and how ample of what may be done by an acute ob- is this power reproduce thus propagated, server and experimentalist, versed in phys- so that an organism can, by single cells, ics and chemistry, but, above all, thorough- multiply itself so rapidly, and, within very ly instructed in scientific methods.
narrow limits, so surely and so interminably? Mr. Darwin's recent two volumes On Mr. Darwin suggests an explanation, by Animals and Plants under Domestication' assuming that each cell or fragment of a are a catacomb of data, observations and plant (or animal) contains myriads of atoms experiments, such as assuredly no one but or gemmules, each of which gemmules he himself could produce. It is hard to say supposes to have been thrown off from the whether it is most remarkable for the num- separate cells of the mother plant, the gember and value of the new facts it discloses, mules having the power of multiplication or for its array of small, forgotten or over- and of circulating throughout the plant ; looked observations, neglected by some their future development he supposes to naturalists and discarded by others, which, depend on their affinity for other partially under his mind and eye, prove to be of developed cells in due order of succession. first-rate scientific importance. An eminent Gemmules which do not become developed surgeon and physiologist (Mr. James Paget) may, according to his hypothesis, be transhas remarked to me, apropos of these vol- mitted through many succeeding generaumes, that they exemplify, in a most re- tions, thus enabling us to understand many markable manner, that power of utilizing remarkable cases of reversion or atavism. the waste materials of other scientific men's Thus, according to this hypothesis, not only laboratories which is a very characteristic, have the normal organs of the body, the feature of their author. As one of those representative elements of which they conpièces justificatives of his previous work, sist, diffused through all the other parts of * The Origin of Species,' which have been the body, but the morbid state of these waited for so long and impatiently, these as hereditary diseases, malformations, &c. volumes will probably have more than their -all actually circulate in the body as mordue influence; for the serried ranks of facts bid gemmules. in support of his theories which they pre- As with other hypotheses based on the sent may well awe many a timid naturalist assumed existence of structures and eleinto bolting more obnoxious doctrines than ments that escape our senses, by reason of that of natural selection. It is in this work their minuteness or subtlety, this of Panthat Mr. Darwin expounds his new hypo-genesis will approve itself to some minds thesis of Pangenesis, which certainly corre- and not to others. To some these inconlates, and may prove to contain the ration- ceivably minute circulating gemmules will ale of all the phenomena of reproduction be as apparent to the mind's eye as the and of inheritance.
stars of which the milky way is composed; You are aware that every plant or ani- others will prefer embodying the idea in - mal commences its more or less independent such terms as “ potentiality," a term which life as a single cell, from which is developed conveys no definite impression whatever, an organism more or less similar to its pa- and they will like it none the less on this rents. One of the most striking examples account. Whatever be the scientific value I can think of is afforded by a species of be- of these gemmules, there is no question but gonia, the stalks, leaves, and other parts of that to Nr. Darwin's enunciation of the which are superficially studded with loosely- doetrine of Pangenesis we owe it that we attached cells. Any one of those cells, if bave the clearest and most systematic réreferred to favourable conditions, will pro- sumé of the many wonderful phenomena of duce a perfect plant, similar to its parent. I reproduction and inheritance that has
appeared; and against the guarded enter-in from the Continent, and Agassiz, in one tainment of the hypothesis, or speculation of the addresses which he issued to his colif you will, as a means of correlating these laborateurs on their late voyage to the Amaphenomena, nothing can be urged as in the zon, directs their attention to this theory as present state of science. The President of a primary object of the expedition they the Linnean Society, a proverbially cautious were then undertaking. I need only add, naturalist, thus well expresses his own that of the many eminent naturalists who ideas of Pangenesis : "If,” he says, " we have accepted it, not one has been known take into consideration how familiar mathe- to abandon it; that it gains adherents matical signs and symbols make us with steadily, and that it is par excellence an numbers and combinations, the actual reali- avowed favourite with the rising schools of zation of which is beyond all human capac- naturalists; — perhaps, indeed, too much ity; how inconceivably minute must be so, for the young are apt to accept such those emanations wbich most powerfully theories as articles of faith, and the creed affect our sense of smell, and our constitu- of the student is also too likely to become tions; and if, discarding all preventions, the shibboleth of the future professor. The we follow Mr. Darwin step by step in ap- scientific writers who have publicly rejected plying his suppositions to the facts set be- the theories of continuous revolution or of fore us, we must, I think, admit that they natural selection, or of both, take their may explain some, and are incompatible stand on physical grounds, or metaphysical
, with others; and it appears to me that Pan- or both. Of those who rely on the metagenesis will be admitted by many as a pro- physical, their arguments usually visional hypothesis, to be further tested, strongly imbued with prejudice, and even and to be discarded only when a more odium, and, as such, are beyond the pale plausible one shall be brought forward.” of scientific criticism. Having myself been
Ten years have elapsed since the publi- a student of moral philosophy in a northern cation of The Origin of Species by Natu- University, I entered on my scientific caral Selection, and it is hence not too early reer full of hopes that metaphysics would now to ask what progress that bold theory prove a useful Mentor, if not quite a scihas made in scientific estimation. The ence. I soon, however, found that it most widely-circulated of all the journals availed me nothing, and I long ago arrived that give science a prominent place on their at the conclusion, so well put by Agassiz, title-pages, the Athenæum, has very recently where he says, “We trust that the time is told it to every country where the English not distant when it will be universally unlanguage is read, that Mr. Darwin's theory derstood that the battle of the evidences is a thing of the past: that natural selection will have to be fought on the field of physiis rapidly declining in scientific favour; and cal science, and not on that of the metathat, as regards the above two volumes on physical." — (Agassiz on the Contemplathe variations of animals and plants under tion of God, in the Kosmos, Christian Erdomestication, they“ contain nothing more aminer, 4th series, vol. XV., p. 2.) Many in support of origin by selection than a of the metaphysicians' objections have been more detailed re-asseveration of his guesses controverted by that champion of natural founded on the so-called variations of selection, Mr. Darwin's true knight, Alfred pigeons.” Let us examine for ourselves Wallace, in his papers on Protection into the truth of these inconsiderate state- (Westminster Review) and “Creation of
Law,' &c. (Journal of Science, October, Since the Origin' appeared, ten years 1867,) in which the doctrines of " continual ago, it has passed through four English edi- interference," and the “theories of beauty," tions, two ·American, two German, two kindred subjects, are discussed with admiFrench, several Russian, a Dutch, and an rable sagacity, knowledge and skill. But Italian ; while of the work on Variation, of Mr. Wallace and his many contributions which left the publisher's house not seven to philosophical biology it is not easy to months ago, two English, a German, Rus- speak without enthusiasm; for putting aside sian, American, and Italian edition are al- their great merits, he, throughout his writready in circulation. So far from natural ings, with a modesty as rare as I believe it selection being a thing of the past, it is an to be unconscious, forgets his own unquesaccepted doctrine with every philosophical tioned claims to the honour of having originaturalist, including, it will always be un- nated, independently of Mr. Darwin, the derstood, a considerable proportion who theories he so ably defends. are not prepared to admit that it accounts On the score of geology, the objectors for all Mr. Darwin assigns to it. Reviews rely chietly on the assumed perfection of
· The Origin of Species' are still pouring the geological record; and since almost all