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BOTANY.

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plastic nature of nervous tissue renders it, in accordance these forms have remained too long a thing apart. Haberwith the principles of natural selection, particularly favour

landt and Goebel have shown us to name no others—how able for progressive change in this direction, and thus happy is the hunting-ground which the Bryophytes provide. developments may occur which reach their highest physio- Further work is still required, directed more especially to logical expression in the brain of man.

certain important points in the life-history. In conclusion, attention may be drawn to the peculiar With the regular vascular cryptogams the relations instability of living processes and structures. The living between the stages are of course different. Here we find units show that significant mutability which the physio- | large complex sporophytes holding the ground, but logist describes as metabolism. This mutability appears to hampered by the ever-recurring necessity of dependence be encouraged or discouraged by the extent to which it upon outside water for the performance of the reproductive fulfils a purpose, and this purpose in a living organism is process. the dominating law of its own development. The fulfil- The land problem was solved on ingenious lines. The ment of this purpose by means of physical and chemical differentiation of gametophytes which accompanied heterochange is such a general characteristic of living processes spory rendered possible the retention of the larger spore that a physiologist may with some confidence suggest that and female prothallus. Thus retained aloft, the drawback this fulfilment is the distinctive mark of a living thing. of the double existence is overcome and the advantages of

the elaborated sporophyte more fully realised. The water

conditions are brought directly under the plant's control SECTION K.

through the device of the pollen-chamber, and the way paved for the ideal seed with siphonogamy.

All the elements of the seed were present before, but OPENING ADDRESS BY PROF. F. W. OLIVER, M.A., D.Sc., combined compactly in this new way we recognise what is F.R.S., PRESIDENT OF THE SECTION.

virtually a fresh stage intercalated in the life-history.

Further elaboration came bit by bit as the possibilities The Seed, a Chapter in Evolution.

were successively realised. With the evolution of the seed, As the subject of the first portion of my Address I propose the plant rose at a bound to a higher plane, and this structo consider the place of the seed in the evolutionary history ture in its perfected form has become the very centre of of plants. The seed-character is the distinctive mark of the plant's existence. three great groups of plants—the Pteridosperms, Gymno- The case of Cycas and Ginkgo with motile sperms affords sperms (including Cordaitez), and Angiosperms. Nor will an extreme demonstration of the inertia of heredity, the it be seriously questioned that the possession of this organ persistence in living seed-plants of the original aquatic has given supremacy to seed-bearing plants over groups flagellate type. not thus characterised in a majority of the types of environ- Obsolete as they are and faced with extinction, these ment where vegetation is able to exist. Exceptions, of survivors from the middle epoch of the world's history course, there are, though few of them are wholly immune still hold their ground in a few scattered localities. In from the invasion of the Spermophyte. The sort of habitat, this connection we shall listen with interest to Prof. for instance, in which Zostera flourishes--sometimes to the Pearson's account of the Encephalartos-scrub of South xclusion of other forms-is held more a result of

Africa which is to occupy us during the course of the vegetative aggressiveness than in virtue of any special present sitting of the Section. power conferred by the seed-habit.

How the sperms became replaced ultimately by the Our stock of knowledge of those plants which had passive cells of the pollen-tube we have no knowledge. attained to the seed-bearing condition in a bygone age has. If the conjecture be well founded that the change came undergone some extension during the last few years; the late rather than early, then the conservatism of the spermoSped, too, has shed its glamour over other branches of phytic line in this respect stands in marked contrast to the morphological inquiry, so that no serious apology is neces- adaptability that is so characteristic of another phylum of sary for its selection as the subject of this morning's aërial plants. The ready evolution of siphonogamy in the discourse.

form of fertilising tubes, so common in the Fungi, perhaps It is generally conceded that the primitive vegetation finds its explanation in the close_filiation of this group arose in the waters, and that with the parting of the with primitive and plastic forms. The fertilising tube may Waters and the emerging of land and continents this reasonably be regarded as a special case of a general primitive stock of plants was sufficiently plastic to take susceptibility to chemiotactic stimuli which distinguished advantage of the new conditions, throwing up successive the whole hyphal complex of the group from very early hordes which effected a footing on the land, and in time times. In the case of the spermophyte, on the other hand, peopled the whole earth with forms adapted to the varying the motile spermatozoid seems to have persisted through a habitats and climates as they differentiated.

long and complicated ancestral history, so that its eliminOf the character of these primæval aquatic types no ation may have been less easy of achievement. direct information has been vouchsafed. It is a matter of · The seed, once evolved, became the centre of a host of inference that they possessed much in common with the accessory organs, constituting what we know collectively green Algæ of to-day, which, living in a biologically stable as the fruit and power. By these it has been robbed, as tredium, are commonly regarded as their nearest represent- we shall see, of many of its pristine functions, and at the atives. Be that as it may, the complexity of the life

time has undergone marked structural reduction. history of existing Algae and the frequent presence of In the highly elaborated Angiosperm more especially we neutral generations seem significant of the capacity of find an almost stereotyped uniformity in seed-structure their progenitors to originate forms with sporophytes contrasting with an infinite diversity in the outward floral adapted to terrestrial conditions.

husk. In our Liverworts and Mosses on the one hand and the In attempting a sketch of the origin of the seed one Ferns and their allies on the other, two divergent evolu- has to admit at the outset that recent discoveries bring tionary lines are represented, both fitted to existence upon us no nearer to its prototype than we were a decade ago. land surfaces, but handicapped by the retention of a non- For the seeds of the Pteridosperms are advanced structures terrestrial nethod of effecting the sexual process. In the recalling quite vividly the type long familiar in living Bryophytes the physiological continuity and dependence of Cycads." It would be overstating the case to say they have the sporophyte upon the gametophyte is preserved through nothing primitive about them, but there is a long chapter out, and it never rises above the status of an elaborate in evolution to be deciphered before we can connect, say, sporr-capsule ; whilst the gametophyte, though often reach- the seed of Lyginodendron with the sporangium of any ing a complex vegetative differentiation, offering many Fern at present known to us. analogies with the sporophytes of higher plants, is con- The great interest of the recent correlation of seeds with dermined to pigmy dimensions through the incubus of the Coal Measure plants lies less in the structure of these inherited aquatic mechanism of fertilisation.

correlated seeds than in the very extensive series of plantThough remote from the series that have culminated in remains which we have thus come to recognise as belonging frd-plants, the Bryophytes are a group offering many an to the earlier Spermophytes. instructive parallel with the main series of plants; certainly For the position of these plants had remained in suspense.

same

The elaborate anatomical investigation which their vege- become caught in the lips of the open megasporangial wall. tative organs had received at the hands of Williamson, This analogy suggests to us that the pollen-chamber cavity Scott, Solms-Laubach, and others showed them to occupy may be a relic or modification of the original place ii a transitional position between the Ferns and Cycads.dehiscence. If this conjecture be true, we have here what In certain respects they showed an advance in the cycadian was once an exit-pore converted to the purposes of ingroas, direction, whilst in others they were wholly fern-like. just as we find, in so many Thallophytes, tubes and beaks, Their fructifications were unknown, and their nature re- once, as it is supposed, the orifices of zoospore discharge. mained an open question. It was for this group, or series now serving for the reception of male gametes. of transitional groups, that Potonié proposed the appro- A great feature in the early seed types was the cumpriate name of Cycadofilices.

plexity of the integument, and this still holds good in We know now that the Lyginodendreæ and Medulloseæ recent Cycads and some other Gymnosperms. Protective bore seeds attached to their fronds. The seeds have been envelopes are so commonly associated with reproductive found attached in some cases to reduced fronds consisting organs, and the nutritive conditions are so favourable of a branching rachis, in others to fronds of the normal their production, that a naked nucellus strikes one da filicinean type. Indeed, so far as habit is concerned, these anomalous. If future research confirm the supposition that plants may rightly be described as seed-bearing Ferns. the ferns which stand in possible relation to early serd

As such, indeed, most people will be content to regard plants were ex-indusiate, like the Marattiaceæ, recent and them—as forms, that is, having close filicinean relation- fossil, then no doubt the seed-coat is a new formation, ship in which the reproductive method has been profoundly having no true homology with, but merely homopla-ti modified, the internal anatomy to a less extent, and the resemblance to, ordinary Fern-indusia. The only case of a habit hardly at all. Had these Pteridosperms come to light naked nucellus that recalls itself is the rather mysterious during the lifetime of Hofmeister that master of morph- instance of Lepidocarpon in which Dr. Scott reports th ology must have pounced upon them as furnishing an not infrequent occurrence of non-integumented megaimportant link in his chain. These fossils and the sperm-sporangia with the prothallus fully developed. atozoa which the Japanese botanists discovered in the seeds The robust nature of the seed envelope, which was oftes of Cycas and Ginkgo, indeed, afford the most convincing drupaceous, is in complete harmony with the whole direct evidence of the soundness of the Hofmeisterian character of the seed if you regard the habit at its incepscheme that it is possible to conceive. Nor is that all. tion as a xerophilous adaptation. And such no doubt if For by confirming the indications first revealed by the was, an improved method whereby the plant became inearlier investigation of the vegetative anatomy, the dependent of chance water at a very critical stage in the Pteridosperms have afforded us a striking object-lesson of life-history. Some of the peculiarities of fossil serd-roats the value of the anatomical method of the significance of especially the ribbing of the Lagenostomas and several purely anatomical characters too long ignored by the other genera, may be attributed to a multiple origin of systematist.

this structure, at any rate in some cases. The remarkable Not so long ago, when new examples of these Pterido- circlet of tentacles which surrounds the summit of Lagersperms were turning up on every hand, some pessimists stoma physoides (best known by Williamson's earlier name were inclined to wonder whether, after all, any groups of Physostoma elegans) suggests that a number of foliar lobtena real Ferns existed in the Palæozoic rocks. Such sporangia have been incorporated in the seed, whilst the presence of as were known might well be the pollen-sacs of seed-bear- perimicropylar ridges and the septate canopy in allied forins ing plants. All doubts on this score are happily set at rest may be taken as only a less evident indication of the stove by the detection of germinating Fern-spores in contem- thing. porary beds. Nor can I think of any more fitting tail- The relation between the integument and sporangial body piece to the investigations which lead the way to the of recent Gymnosperm seeds is found to be an inconstant Pteridosperms than the discovery, by the same investigator, character, and the same is true of the fossils. In general of the antidote to these rather disturbing views. However, character the relationship recalls that which obtains between it is needless to dwell further on these matters now, in the ovary and receptacle of an Angiosperm. The Lacenoview of Dr. Scott's address to-morrow upon the Present stomas resemble Cycas and Pinus in having the integument State of Palæozoic Botany.

free at the apex only. whilst Taxus, Phyllocladus, and But to return to the history of the seed. In the absence Araucaria are in agreement with the Trigonorarpons and of direct evidence, one can only conjecture that some old other seeds, which are generally attributed to Medulloux generalised type of sporangium formed its prototype, some- in having an integument which rises freely from ththing substantial, on the lines of a Botryopteris or Zygo-chalaza. It is interesting to note that the fossil seeds o pteris, perhaps. The heterospory that was the precursor the latter group show an additional complexity in the wa!! of the seed-like condition must have been a transient phase, of the nucellus. For in them a series of trachcal strand or else it is lost in the pre-Carboniferous obscurity. Be or even a mantle of tracheides is found running up from that as it may, the passage from the dehiscent to the the chalaza to the pollen-chamber. It is evident that indehiscent monosporal megasporangium finds its analogy nothing was spared in these older seeds to ensure adequate in every group of plants. Where there is extreme numerical access of water to the pollen-chamber where the speriais reduction of the contained structures-be they spores or must have been liberated. seeds--a multitude of cases in the Fungi, in the Algæ, and In due time the protective sheath, or testa, appropriate the angiospermie flowering plants show that dehiscence other functions supplementary to that of protection. Of tends to become obsolete. The failure to dehisce does not these the most important must have been the reception of appear to be directly correlated with any mechanical diffi- the pollen. A very striking feature in all the Lagencculty in ejaculation. It is more probably one of those stomas is the way in which the tip of the nucellus (wher obscure cases of interdependence of phenomena in which the orifice of the pollen-chamber is situated) projects besond the vegetable kingdom abounds. A special investigation the integument. In these seeds the microspores must havr directed to the plucidation of this point might be expected had direct access to the pollen-chamber without first d. to .vield interesting results.

scending a micropylar canal. We now come to the consideration of a most character- In the Medullosean seeds also the nucellus is dis istic organ o! the seed--the pollen-chamber. This cavity tinguished by a long beak, as Dr. Scott and Mr. Vasien arises at the apex of the megasporangium, above the big have shown recently for Trigonocarpon, and, as we know megaspore, and is found in all the Palæozoic seeds, with in Stephanospermum, and many other cases. So far as ar the sole exception, so far as I am aware of the seed- know, this beak does not extend to the surface, though is

structures in Lepidocarpon and Miadesmia. The engages with the micropylar canal, and is continued sur utility of the pollen-chamber is manifest, but its ante. distance up. cedents are quite unknown. l'pon such a structure as this Though it can hardly be supposed that the long beak lus may have depended the success of the seed-method at been inherited from the ancestral sporangium, its preunir critical stage

in its evolution. In the viviparous may be none the less significant of what took plair aber Selaginellas, described some years ago in America, the the seed method was initiated. The direct pollination in archegonium on the prothallus of the retained megaspore Lagenostoma may well be a survival from the old dars is fertilised by sperms liberated from microspores which when no proper micropyle existed. But when the mini

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pyle closed in, the conservative nucellus would for a while be that we have here but one more illustration of the endeavour to maintain direct communication with the operation of temperature as the limiting factor, but in any exterior. The beak-like appendage on this view would be case the matter wants clearing up. An experimental ina new formation evolved pari passu with the integument. vestigation of the relations of “ albuminous " and “ex

A peculiar and distinctive, though negative, feature albuminous." Seeds would probably repay the trouble common to the whole range of Palæozoic seeds that have involved. Does any condition or set of conditions under become known to us is the lack of an embryo. Occasion- the control of the operator exert an influence in this conally small-sized seeds are met with, as in Lagenostoma nection? Lomaxi, and now and then immature-looking stages, of The mention of the early germination of seeds brings to which the best example is Renault's Cordaitean ovule, so mind the most striking instance of all—that of the tropical often figured in the books. But apart from such rarities Mangrove, in which, as is so well known, the seed the petrifactions agree in being at a stage which, in the germinates on the tree, so that the young plant is extruded, light of recent Cycads, is to be interpreted as corresponding and in some instances falls, from the parent free of its to the time of fertilisation. The pollen-chamber is charged envelopes. with pollen-grains, whilst in good examples the megaspore Our interest in this type of vegetation has been revived is filled with a prothallus which frequently shows indica- through the researches of Mr. H. B. Guppy incorporated tions of archegonia at its upper extremity. All these in his recent contribution Plant-dispersal in the specimens will be dismissed by some as abortive, and any Pacific.” This volume, perhaps the most important conconclusions drawn from the negative character as invalid. tribution to the biology of tropical plants that has appeared Without ignoring this contingency another view is, of since the death of the lamented Schimper, is distinguished course, possible. The normal fall of the seed may have alike for its wealth of new observations and its engaging followed pollination at a short interval, much as is reported freshness of treatment. There is one suggestion of Mr. for Cycas and Ginkgo to-day. The resting period " in Guppy's concerning the vivipary of Mangroves which may these seeds would then perhaps coincide with the matura- occupy our attention for a few moments. tion of the sperms, whilst the subsequent embryonic history As a result of his studies in the Pacific and elsewhere might have been carried through without a pause. This Mr. Guppy has arrived at the conclusion that the Manview gains support from the filicinean relationship, for of grove type of vegetation is a very ancient one, dating back course the fertilised egg of a Fern continues its develop- to the times when climate was more uniform and moist ment without interruption. If the modification of the than we know it to-day. The viviparous habit he corpteridophytic life-history that culminated in these early jectures to have been once very general, whilst to-day this Seeds were directed, as seems probable, to ensuring a primitive condition is making last stand along the greater certainty in bringing the gametes together under tropical shores. Traces of vivipary still occur among conditions favourable to their union, it would follow that inland plants, such as Crinum, whilst in other cases it rethe other great advantage arising from the seed-habit was appears intermittently under conditions not fully ascerof later acquisition. In other words, the ordinary seed tained. Mr. Guppy supposes the ordinary fruiting way of with resting embryo was evolved by stages. There is a plants with caducous fruits or seeds, that germinate after great lacuna in our knowledge of the early adjustment of an interval, to have arisen by a modification of the conthe embryo to intraseminal existence. Whilst evidence of tinuous viviparous method in the sense that the seed has Palæozoic seeds with resting embryos is altogether want

to fall earlier and earlier until the stage now ing. We are confronted in the Mesozoic rocks with the characteristic of practically all Spermophytes has been Bennettiteæ, all of which possess a well-marked dicotyle- reached. donous embryo practically filling the seed-cavity. It is

Piecing the data together, this seems to be the position : mere conjecture to suggest that this change has been The earliest known seeds appear to have remained on the wrought in response to some climatic stimulus, though the plant just long enough to receive their pollen ; but in time, marked xerophilous facies of many of the Mesozoic Cycado- it is reasonable to suppose, the advantage of remaining phyta seems quite consistent with such a view. Be that longer was realised, and the fall of the seed was postponed as it may, one cannot fail to recognise that the resting seed until fertilisation was followed by the occupation of the with an embryo marks a great advance on the Pterido- seed-cavity by an embryo. Here in seclusion the embryo spermi, an advance hardly less important to the welfare of could remain until germination was convenient. Starting the plant than was the earlier type of seed on the extended at the other end, our modern seed, according to Mr. Guppy; life-history of the filicinean prototype.

has been evolved by the gradual retention of the viviparous This stage of the seed-history would be of exceptional embryo; or, to put it in another way, the detachment of interest if we could hope to recover any morsels of direct the seed has been hastened so that it falls long before evidence. As yet we remain in the dark as to the morpho- germination is due. logical nature of the embryonic organs, how far we are Well, these theories fail to meet in the middle, as ther dealing with new structures produced from a protocorm, should if they are to present us with an epitome of the as Prof. Bayley Balfour has suggested ; ' how far they

whole seed-history. Perhaps there were troublous times in represent the old filicinean organs adjusted to intraseminal

that middle epoch, so that the continuity has become life. What chance there may be of the solution of this

obscure! Or possibly another view may be admissible of difficult problem by the application of other methods may

the relation of vivipary to normal seed-production. Most merge perhaps from the discussion on the phylogenetic botanists, I take it, have been inclined to regard vivipary value of early seedling characters which is to be opened

as the dernier cri in seed-history, the ultimate stage in next Tuesday morning by my colleagues Mr. Tansley and Miss Thomas.

the way of possible reproductive advance in seed-bearing Reference has already been made to the view that the Mangrove process might even be conceived as the starting;

methods that the higher plants have yet attained. The sued, as we find it in the majority of spermophytes with

point, under certain contingencies, of a whole new race of its resting embryo, shows definite adaptation to seasonal

plants with life-histories complicated by fresh alternations pariodicity. It would be interesting to learn how far the

-homologous alternations—far beyond any of which we serds of plants long accustomed to uniform conditions, such as the rainy tropical forest, behave in this respect.

have knowledge to-day!

Schimper and others who have given attention to the The point does not appear to have been very fully investigated. Indeed, there is a rich field for both observational subject found no reason for regarding vivipary as other

than an adaptation to special circumstances, an extreme and experimental work upon obscure seed-problems await. ing any one who can devote continuous attention to the

condition that had arisen independently in several cycles subjert. Is there any solid foundation for the supposed

of affinity. Before the contrary can be accepted a good " physiological dimorphism”

deal of positive evidence will be needed, drawn from the among seeds according to which, as one reads in the older books, the earlier ripening

non-Mangrove representatives of groups in which viviparı pods are adapted to an immediate germination, whilst the

occurs, to show that the relationship is other than has Latre ones are reserved for the following spring? It may

been generally supposed. Moreover, if the viviparous habit

were formerly of wide occurrence some traces of it might 1 Presidential Address, Section K, Glasgow, 1901, p. 9.

reasonably be expected in the fossil record. So far as can

be ascertained, such have not been forthcoming, nor can The history of the seed, as I read it from the imperfect I hear of any record of recent Mangroves being preserved and fragmentary data that are available, has been a series in this way. Seeds and embryos appear to be so uniform of advances spread over long geological periods. The on the whole that it is difficult to understand how they possibilities of the seed-habit were realised only bit by bit, could have passed through a viviparous phase in the later and the high efficiency of the modern seed depends in large stages of their evolution.

degree upon the close association of other structures which The viviparous Mangroves, on the other hand, are full cooperate in its functions. No doubt the first step, the of diversity in detail, and these differences would surely retention of the megaspore, was the most important of have left a permanent mark had the course pursued been all; though, that this might be effective, some contrivance in conformity with Mr. Guppy's very interesting sugges- for the capture of the pollen-grains must have accompanied tion. That there is a rich field awaiting detailed investi- | it. Later steps in the process of seed-evolution would gation in connection with the fascinating subjects opened include the adjustment of an intraseminal embryonic stage, up by Mr. Guppy will be admitted by most naturalists. and in time the substitution of the pollen-tube for the

In glancing back at the early seed-structures one is ' liberation of sperms. struck with the complexity of their organisation as com- Now assuming, as I think we are entitled to assume, pared with the relative simplicity of modern seeds. The that seeds have come into existence along some such lines pollen-chamber, the large elaborate integument, and the as those thus crudely blocked out, there is a great difficulty complicated vascular arrangements, so characteristic of the in conceiving the process other than discontinuous. Every Pteridosperm seed, have for the most part passed away, one of the stages. emphasised involves the conception of giving place to much simpler structures. Occasional ex- something more abrupt than mere gradual variation. And ceptions no doubt occur; the seeds of Palms have remark- there is, of course, the old difficulty confronting us as to able integuments, whilst those of Magnolia, some Aroids, how the organ or mechanism came to be preserved at its Sapotaceæ, &c., show an unusual development of vascular inception. All these difficulties vanish when it is recog. tissue. Most astonishing of all perhaps is the integu- nised that effective variation is of the discontinuous order, mental tracheal sheath which closely invests the nucellus and that the successive changes involved may be consider. of Cassytha. Though evidence of their precise function be able enough to be designated jumps. Happily such views, lacking, the fact that many of these structures belong to based upon experimental results, have been formulated by the tropical forest makes closer knowledge desirable. For De Vries in his Mutation Theory. That theory is so well in these localities the conditions must have long been known to botanists in this country that any exposition here relatively stable; thus increasing the chance that the struc- is quite superfluous. The least ihing that can be said in tures referred to still perform their pristine functions. its support is that it is perfectly tenable. But we may go These and other cases like them need elucidation, but to much further than that. Apart from the Theory of the broad statement that the seeds of recent Spermophytes Natural Selection, no modern hypothesis of evolution has are organised on simple lines there can be no question. been so helpful or so likely to stimulate further work. This reduction in complexity may be accounted for on two The results of continued investigations in this field, now grounds. In the first place fertilisation by motile sperms so actively pursued, will be awaited by all biologists with has been replaced by fertilisation by pollen-tubes. Instead a keen and sympathetic expectancy. Not the least of the oi sperms being discharged into an internal water-chamber advantages that follow in the wake of the Mutation Theory upon which the archegonia abutted, the male cells are is the shortening of the time required for the evolutionary carried through soft tissues to the egg in a plastic tube.

process. As the physicist imposes a time limit to the In other spheres the like befalls. If primitive man had period during which life has been possible on the earth, occasion to journey from Baker Street to Waterloo, he

a working theory that reconciles the demands of the penetrated the forest and then swam the river ; to-day his biologist with the physical limitations is decidedly redescendants are projected from the one to the other with assuring. In this connection it is very interesting to note accuracy and despatch in a subterranean passage.

that Monsieur Grand'Eury, one of the most active and Just at what stage the improvisation of the pollen- distinguished workers in the field of palæobotany, should chamber gave place to the newer method we have no have found data supporting the view of mutation." In knowledge. Perhaps some information on this point may tracing the passage of fossil plants through great thickemerge from Dr. Wieland's exhaustive researches into the

nesses of rock he has been impressed on the one hand with extensive Yale collections of American Cycadeoideas. For the high degree of permanence of certain forms, and op the Bennettiteæ already show a simplification of the seed the other with the suddenness, when the moment came. in certain respects; though, owing to the late stages of with which one species passes into another. development usually found in European examples, this point The collection of data of this kind from our own Coal could be cleared up.

Measures appears to me a very pressing necessity in view The other cause that must have played a prominent part of the rapidity with which the coalfields are being in the simplification of the seed was the association with exhausted.. Indeed, the present is an unique opportunity it of other structures which relieved of a part of the which can never recur, and the chance of systematicalls original load of duties that fell to its lot. The dense heads

utilising it is slipping away. Whatever view one may hold of Bennettites show us this, and the same may be said as to the expediency of making exhaustive collections of of most Coniferous strobili. But the Angiospermic ovary the recent flora, there can be no two opinions of our provides the best example of a special organ inclosing the manifest duty to "make hay while the sun shines" in seed or ovule, affording it protection during the immature the matter of the coal fossils: Regarded as systematicall * stages and also collecting the pollen. The steps by which arranged collections showing how the plants occur in this came about remain hidden, and any discussion of the definite localities, the contents of most of our museuins, matter is of course premature. The carpels may have as I am assured by competent authorities, are practicalls been derived from reduced sporophylls or from portions of worthless. That innumerable specimens of the greatest sporophylls that were more closely associated with the

value are preserved in museums inay be readily conceded; seeds. The cupule of Lyginodendron is an organ rather but my point is that these collections have been made suggestive in this connection. One is tempted to compare without system, and that details of precise localitt und it with a rudimentary ovary, playing the serviceable part horizon are frequently wanting. All this has to be de of a moist air-chamber for the seed during the earlier over again, and I believe local societies working in touch stages of its development.

with a central organisation could do a memorable service However, the origin of the fruit and of the flower, with which would earn them the gratitude of future generations all its manifold organs, must be left to the future: they

and at the same time provide a fresh outlet to their form no part of our theme. Some day a happy discovery energies. will yield a clue, and the reproach that we are in entire To us the coal industry, with its vast resources, is * ignorance of the affinities of the dominant phylum will be convenient mechanism for making fossil plants accessible

. removed.

The colliery proprietor may be relied on to afford all

reasonable facilities for the acquisition of select examples 1 M. Mirande, "Le dévelop. et l'anat. d. Cassythacées," Ann. d. Sc. Nat., o sér. bot., tom. ii., 1905

i Grand'Eurs, Comptes rendus, tom. cxlii p. 19,

from these superabundant and embarrassing waste pro- | is, I hope, less urgent now than formerly. Already at the ducts. Should he incline to go further and contribute time of the last meeting in York (1881) a select band of towards the modest íunds necessary to carry out the under- Englishmen were at work upon original investigations of laking worthily, he would increase the debt which science the modern kind. The individuals who formed this little uwes to industry. The thousandth part of the revenue group of pioneers in their turn influenced their pupils, and arising from the export tax on coal would amply suffice so the movement spread and grew. It would be premature for the purpose. Indeed, I can think of no more appro- to enter fully into this phase of the movement, so I will priate way of celebrating the abolition of that burdensome pass on with the remark that modern botany was singularly impost.

fortunate in its early exponents. I have dwelt to-day on the seed to the exclusion of Whenever the history of botany in England comes to be other features, it is because I am convinced of its supreme written, one very important event will have to be chronicled. importance. The evolution of the seed must have been one This is the foundation of the Jodrell Laboratory at Kew, of the most pregnant new departures ever inaugurated by which dates from the year 1876. Hidden away in a corner plants. The revelations of the last few years afford us, it of the Gardens this unpretentious appendage of the Kew is true, but the merest glimpse of the first stage reached, establishment has played a leading part in the work the rise of the Pteridosperms. The conquest of the world of the last twenty-five years. Here you were free to must have been slow then as it is now. The great forests pursue your investigations with the whole resources of the of Lepidodendrons and Calamites were not reduced to mere Gardens at your command. I suppose there is hardly a Lycopodiums and Equisetums all at once.

In this pro

botanist in the country who has not, at some time or other, longed struggle, even if the Lycopods never produced a availed himself of these facilities, and who does not cherish race to share the spoils, as some suppose, there is the the happiest memories of the time he may have spent there. evidence of Lepidocarpon that their reproductive methods Certainly Jodrell displayed rare sagacity in his benefacunderwent a certain if ineflectual modification in the same tions, which included, in addition to the laboratory that direction as their eventual supplanters. Probably the seed bears his name, the endowments of the Chairs of Animal plants asserted themselves wherever physical changes over- Physiology and Zoology at University College, London. whelmed old habitats. The rise and fall of the land, so Sir William Thiselton-Dyer, who has so recently retired great a feature in Carboniferous times, would favour the from the Directorship of Kew, had every means of knowyounger group. For as new ground became available for ing that his happy inspiration of founding a laboratory at colonisation there would be opportunity of competing on at

Kew was a most fertile one. It would not be surprising least equal terms with the effete types that cumbered the if the future were to show that of the many changes forest land. Nor should we forget that the seeds were well inaugurated during his period of service this departure equipped with dispersal-mechanisms almost as varied as should prove by far the most fruitful. they are to-day.

Another incident belonging to the early days ought not A somewhat similar struggle is now in progress between to be overlooked : I refer to the notable concourse of Conthe Angiosperms and Gymnosperms, but so slowly that we tinental and American botanists at the Manchester meeting hardly notice it. A future age may have to be content to of the British Association in 1887. The genuine interest know its Gymnosperms from dwarf forms like those which which they evinced in our budding efforts and the friendly the Japanese are so fond of producing in their pot-cultiva- encouragement extended to us on that occasion certainly tions! But perhaps all calculations will be upset by the left an abiding impression and cheered us on our way. more effective intervention of the human race.

On present

We are not forgetful of our obligations. We regard indications the vegetation of the future should consist of them in the light of a sort of funded debt on which it is cultivated crops and the weeds that accompany them ; that at once a pleasure and a duty to pay interest. The diviis, unless the Chemist comes to our aid and solves the dends, I believe, are steadily increasing-a happy result problem on other lines.

which I am confident will be maintained. Botany in England.

But I should be lacking in my duty did I permit the

impression to remain that botany is anything but a sturdy I now turn to other matters. The period of twenty-five and natural growth among us. The awakening, no doubt, years that has elapsed since the British Association last met

came late, and at first we were influenced from without in in this City all but includes the rise of modern botany in

the subject-matter of our investigations. But many lines this country. During the middle decades of last century

of work have gradually opened out, whilst fruitful new our botanists were preoccupied with arranging and de departures and important advances have not been wanting. scribing the countless collections of new plants that poured

We still lean a little heavily on the morphological side, in írom every quarter of an expanding empire. The

and our most urgent need lies in the direction of physiomethods inculcated by Linnæus and the other great taxo

logy. As chemists and physicists realise more fully the nomists of the eighteenth century had taken deep root

possibilities of the “botanical hinterland,” one may expect with us and choked out all other influences. Schleiden's

the conventional frontier to become obliterated. As Mr. "Principles of Botany," which marked a great awakening

F. F. Blackman has pointed out in a recent interesting elsewhere, failed to arouse us. The great results of Von

contribution, the chemist's point of view has undergone Mohl, Hofmeister, Nägeli, and so many other notable

a change with the growth of the science of physical chemworkers, which practically transformed botany, were

istry, and is now much more in line with that of the first without visible effect.

biologist than was formerly the case. This natural passage It was not that we were lacking in men capable of

from the problems of the one to those of the other should appreciating the newer work. Henfrey, Dr. Lankester

be the means of attracting into our body recruits possessing (the father of our President), not to mention others, were

the necessary chemical equipment to attack physiological continually bringing these results before societies, writing

problems. about them in the journals, and translating books. But

As the position gains strength on the physiological side, the thing never caught on-it would have been surprising it will become possible to render more effective service to if it had. You may write and talk to your contemporaries agriculture and other branches of economic botany. to your heart's content, and leave no lasting impression.

This is of importance for a variety of reasons. Among The schools were not ready. No movement of the sort

others it will bring public support and recognition which could take root without the means of enlisting the sym

will be all for good, and it will provide an outlet for pathies of the rising generation. It was only in the 'seven

our students. It will also afford unrivalled opportunities ties that effective steps were taken to place botany on the

for experiments on the large scale. Even should economic higher platform; and the service rendered in this connec

conditions, which compel us to import every vegetable tion by Thiselton-Dyer and Vines is within the knowledge

product, continue to prevail in this country, this will not of us all. Like the former in London, so the latter at

be so in the Colonies. As time goes on, one may reasonCambridge aroused great enthusiasm by his admirable courses of lectures. Great service, too, was rendered by ably expect an increasing demand for trained botanists,

ready to turn their hands to a great variety of economic the Clarendon Press, which diffused excellent translations of the best Continental text-books-a policy which it still

problems. pursues with unabated vigour, though the need of them

1 "Incipient Vitality,” New Phytologist, vol. v. p. 22.

at

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