# Makers of British botany/Sir William Hooker 1785—1865

SIR WILLIAM HOOKER 1785—1865
By F. O. BOWER
Early pursuits—appointed to Glasgow—Garden administration—teaching methods—appointed Director of Kew—state of Botany—vigorous development of Kew—serial publications—floristic work—descriptive work on Ferns—his record.
"Poeta nascitur non fit." A poet is born, not made. If this be true of poets, much more is it true of botanists. The man who takes up botany merely as a means of making a livelihood, rarely possesses that true spirit of the naturalist which is essential for the highest success in the Science. It is the boys who are touched with the love of organic Nature from their earliest years, who grub about hedgerows and woods, and by a sort of second sight appear to know instinctively, as personal friends, the things of the open country, who provide the material from which our little band of workers may best be recruited.
Such a boy was Sir William Hooker, the subject of this lecture. He was born in 1785, at Norwich. There is no detailed history of his boyhood, but it is known that in his school days he interested himself in entomology, in drawing, and in reading books of natural history, a rather unusual thing at the time of the Napoleonic wars! In 1805, when he was at the age of 20, he discovered a species new to Britain, in Buxbaumia aphylla, and his correspondence about it with Dawson Turner shows that he was already well versed not only in the flowering plants, but also in the Mosses, Hepaticae, Lichens, and fresh-water Algae of Norfolk, his native county. Three years later Sir James Smith dedicated to him the new genus
* Plate XII
* WILLIAM JACKSON HOOKER (1834)
​Hookeria, styling him as "a most assiduous and intelligent botanist, already well known by his interesting discovery of Buxbaumia aphylla, as well as by his scientific drawings of Fuci for Mr Turner's work: and likely to be far more distinguished by his illustrations of the difficult genus Jungermannia, to which he has given particular attention" (Trans. Linn. Soc. IX. 275). Clearly young Hooker was a convinced naturalist in his early years, and that by inner impulse rather than by the mere force of circumstances.
Not that the circumstances of his early years were in any way against his scientific tastes. He inherited a competence at the early age of four, and so was saved the mere struggle of bread-winning. His father was personally interested in gardening, while from his mother's side he inherited a taste for drawing. Moreover, he was early thrown into relations with some of the leading naturalists of his time, chiefly it appears by his own initiative, and doubtless he owed much in those opening years to the advice and stimulus of such men as Dawson Turner, and Sir James Smith. Elected to the Linnean Society in 1806, he became acquainted in the same year with Sir Joseph Banks, Robert Brown, and other leading naturalists. Thus when other young men would be feeling for their first footing, he at the age of 21 had already penetrated into the innermost circle of the Science of the country. For a period of sixty years he held there a place unique in its activity. He shared with Augustin Pyrame De Candolle and with Robert Brown the position of greatest prominence among systematists, during the time which Sachs has described as that of "the Development of the Natural System under the Dogma of Constancy of Species." The interval between the death of Linnaeus and the publication of the Origin of Species can show no greater triumvirate of botanists than these, working each in his own way, but simultaneously.
The active life of Sir William Hooker divides itself naturally into two main periods, during which he held two of the most responsible official posts in the country, viz. the Regius Chair of Botany in Glasgow and the Directorship of the Royal Gardens at Kew. We may pass over with but brief notice the years from 1806 to 1820, which preceded his attainment of ​professorial rank. Notwithstanding that notable work was done by him in those years, the period was essentially preparatory and provisional, and can hardly be reckoned as an integral part of his official life. He was in point of fact an enthusiastic amateur, one of that class which has always been a brilliant ornament of the Botany of this country, and has contributed to its best work. He travelled, making successive tours in Scotland and the Isles, no slight undertaking in those days (1807, 1808). In 1809 he made his celebrated voyage to Iceland, described in his Journal, published in 1811. But his collections from Iceland were entirely lost by fire on the return voyage. His son remarks that the loss to science was probably greatest in respect of the Cryptogamic collections; this naturally followed from the fact that already he had taken a prominent place as a student of the lower forms, and the field for their study was more open than among the flowering plants of the island. It was among the Cryptogams that Sir William found the theme of his first great work, the British Jungermanniae, published in 1816. Nearly a century after its appearance it still stands notable not only for the beauty of the analytical plates, but as a foundation for reference. It must still be consulted by all who work critically upon the group, subdivided today, but comprehended then in the single genus Jungermannia. During this period he also produced the Musci Exotici, with figures of 176 new species from various quarters of the globe. Thus up to 1820 his chief successes lay in the sphere of Cryptogamic Botany.
Naturally so ardent a botanist desired to widen his experience by travel. But circumstances checked the projects which he successively formed to visit Ceylon and Java, South Africa, and Brazil. In 1814 he went to France, and became acquainted with the leading botanists of Paris. He proceeded to Switzerland and Lombardy, returning in 1815, in which year he married the eldest daughter of his friend Mr Dawson Turner. Meanwhile, at his father-in-law's suggestion he had embarked in a business for which he was not specially fitted by experience or by inclination. It did not prove a success, and as the years drew on, having a young family dependent upon him, he began ​to look out for some botanical appointment which should at once satisfy his personal tastes, and be remunerative. The chair in Glasgow becoming vacant in 1820 by the transfer of Dr Graham to Edinburgh, he received the appointment from the Crown, largely through the influence of Sir Joseph Banks. He entered upon its duties never having lectured before to a class of students, nor even heard such lectures, but otherwise equipped for their performance in a way that would bear comparison with any of the professors of his time.
Glasgow was in 1820 at an interesting juncture in its botanical history. Though the science of botany had been taught for a whole century in the University, a separate chair had been founded by the Crown only two years before. Moreover, though there had been for a long period a "Physic Garden" in the grounds of the old College, this had proved insufficient, and its position within the growing town unsuitable. Accordingly, in part by grant from the Crown, partly from the funds of the University, but largely by the subscriptions of enthusiastic citizens a Botanic Garden had been founded under Royal Charter in 1817, and opened to the public in 1819. The first blush of novelty had not worn off this new enterprise when a man, already in a leading position, whose successful achievements had shown his quality, acquainted with many of the leading botanists of Europe, and with youth and unbounded energy at his disposal entered upon the scene, and began that course of organisation of Public Botanic Gardens which he continued to the day of his death.
There was nothing to prevent the Glasgow establishment from rapidly taking a leading position. Largely as the result of Hooker's influence and initiative, and assisted greatly no doubt by the zeal with which the movement was supported by individual citizens, and aided by the position of Glasgow as a great commercial centre, contributions to the garden began to come in from every quarter of the globe. Taking the number of species represented as a measure, the growth of the living collections was rapid beyond precedent. In 1821 the number of species living in the garden was about 9000: in 1825 it is quoted at 12,000, while the increase in number from that period ​onwards was about 300 to 500 per annum. Of these a large number were new species, not previously described or figured. This work Hooker carried out, and the publication of his results widened still further the desire of the officials of other gardens to effect exchanges. In 1828, after it had been in existence but ten years, the Glasgow garden was corresponding as an equal with 12 British and Irish, 21 European, and 5 Tropical gardens, while it had established relations with upwards of 300 private gardens. In 1825 Sir William Hooker published a list of the living plants in pamphlet form, with a plan of the garden, copies of which are still extant. But the following years, from 1825 to 1840 were the most notable in its history as a scientific institution. It is recorded in the minute books that scientific visitors almost invariably expressed the opinion that the garden would not suffer by comparison with any other similar establishment in Europe. It can hardly have come as a surprise to those who had witnessed his work in Glasgow that when a Director had to be appointed to the Royal Gardens at Kew, the post was offered to Hooker. He accepted the appointment and left Glasgow in 1841.
His conduct of the Glasgow professorship from 1820 to 1841 was a success from the first, notwithstanding his entire want of prior experience of such duties. Sir Joseph Hooker, in his speech at the opening of the New Botanical Buildings in Glasgow University, in 1901, pointed out how he "had resources that enabled him to overcome all obstacles: familiarity with his subject, devotion to its study, energy, eloquence, a commanding presence, with urbanity of manners, and above all the art of making the student love the science he taught." Not only students in medicine, for whom the course was primarily designed, attended the lectures, but private citizens, and even officers from the barracks.
Sir Joseph describes his father's course as opening with a few introductory lectures on the history of botany, and the general character of plant-life. As a rule the first half of each hour was occupied with lecturing on organography, morphology, and classification, and the second half with the analysis in the class-room of specimens supplied to the pupils, the most studious of whom ​took these home for further examination. An interesting event in these half-hours was the professor calling upon such students as volunteered for being examined, to demonstrate the structure of a plant or fruit placed in the hands of the whole class for this purpose. The lectures were illustrated by blackboard drawings, probably these were a special feature in the hands of so experienced an artist as he, and also by large coloured drawings, chiefly of medicinal plants, which were hung on the walls. Another feature, which happily still survives, was the collection of lithographed illustrations of the organs of plants, a copy of which was placed before every two students. The first edition of these drawings appears to have been by his own hand. But in 1837 a thin quarto volume of Botanical Illustrations was produced, "being a series of above a thousand figures, selected from the best sources, designed to explain the terms employed in a course of Lectures on Botany." The plates were executed by Walter Fitch, who was originally a pattern-drawer in a calico-printing establishment, and entered the service of Sir William in 1834. This great botanical artist continued to assist Sir William till the death of the latter, and himself died at Kew in 1892. A number of copies of this early work of Fitch remain to the present day in the Botanical Department in Glasgow.
Other branches, however, besides Descriptive Organography were taken up. Naturally the plants of medicinal value figured largely in the course, which was primarily for medical students. Illustrative specimens, of which Sir William gathered a large collection, were handed round for inspection. These, together with other objects of economic interest finally made their way to Kew, and were embodied in the great collections of the Kew Museums. The branch of anatomy of the plant-tissues was not neglected. Of this he wrote at the time of taking up the duties of the chair, "it is a subject to which I have never attended, and authors are so much at variance as to their opinions, and on the facts too, that I really do not know whom to follow." He continues with a remark which is singularly like what one might have heard in the early seventies, just before the revival of the laboratory study of plants in this country. He remarked that "Mirbel has seen what nobody else can: so nobody contradicts ​him, though many won't believe him." I can hardly doubt that physiology of plants will also have figured in the course, first because Sir William was himself a successful gardener, but secondly because we have in the Botanical Department in Glasgow the syllabus of the lectures of Professor Hamilton who taught botany in the University in the latter end of the 18th century. In this course physiology took a surprisingly large place, and we can hardly believe that it would have dropped out of Sir William's course altogether. But of this there is no definite record.
Another feature of the teaching of Sir William was the practical illustration of botany in the field, by means of excursions. Of these Sir Joseph tells us there were habitually three in each summer session, two of them on Saturdays, to favourable points in the neighbourhood of Glasgow; but the third, which took place about the end of June, was a larger undertaking. With a party of some thirty students, and occasional scientific visitors from elsewhere, he started for the Western Highlands, usually the Breadalbane range. In those days, before railways, and often with indifferent roads, this was no light affair, and in some cases it involved camping. I do not know whether this was the beginning of those class excursions which have been so marked a feature in the botanical work of the Scottish Universities, but it is to be remembered that his immediate successor in the Glasgow chair was Dr Hutton Balfour, who in later years confirmed and extended the practice, and it has been kept up continuously in the Scottish universities ever since. It was to meet the requirements of such work in the field that Sir William prepared and published the Flora Scotica. The first edition appeared before his second year's class had assembled in 1821. The first Part related to the Phanerogams only, arranged according to the Linnaean system. The second, which seems to have been almost as much a new book as a second edition, contained the Phanerogams arranged according to the natural system, just then coming into general use. It also embodied the Cryptogams, in the working up of which he had the assistance of Lindley and of Greville. The total number of species described was 1784, of which 902 were Cryptogams.
​And thus was initiated that profuse and rapid course of publication which characterised the period of office of Sir William Hooker in Glasgow. The duties of the chair were comparatively light, and only in his later years did he extend them voluntarily into the winter months. He worked year in year out, early and late, at his writing, and rarely left home. The 21 years of his professorship were perhaps the most prolific period of his literary production. It was brought to a close in 1841, by his appointment to the directorship of the Royal Gardens at Kew, which had in March 1840 been transferred from the Crown, under the Lord Steward's Department, to the Commissioners of Woods and Forests. Sir William had been for some time desirous of changing the scene of his activities from the relatively remote city of Glasgow to some more central point, and the opening at Kew not only satisfied this wish, but also put him in command of the establishment in which he saw, even in its then undeveloped state, the possibility of expansion into a botanical centre worthy of the nation.
In the spring of 1841 Sir William removed to Kew, taking with him his library, his private museum and herbarium. This was the first of those incidents of denudation of the botanical department in Glasgow, the direct result of the system that held its place in the Scottish Universities till the Act of 1889. Till that date the chair was "farmed" by the professor. Almost all the illustrative collections and books of reference were his private property. Whenever, as has repeatedly been the case in Glasgow, the occupant of the chair was promoted elsewhere, he naturally took his property with him, and the University was denuded, almost to blank walls. Fortunately that is so no longer. But in the present case the collections were removed, and finally formed the basis of the great museums, and of the herbarium of Kew.
At the time of Sir William's appointment Kew itself was in a very unsatisfactory state. The acreage of the garden was small compared with what it now is. The houses were old, and of patterns which have long become obsolete. Only two of them are now standing, viz. the Aroid house near the great gates, and the old Orangery, now used as a museum for timbers. ​There was no library, and no herbarium. In fact Kew in 1841 was simply an appanage to a palace, where a more than usually extensive collection of living plants were grown. In the course of the negotiations which led up to the transfer to the Department of Woods and Forests it had even been suggested that the collections themselves should be parted with. It was to such an establishment, with everything to make, and little indeed to make it from, that Sir William Hooker came at the age of 55. He had, however, unbounded enthusiasm, and confidence in the public spirit, and in himself: and what was still more to the point, the experience gained in the smaller field of Glasgow, in building up the garden there, combined with a knowledge of plants which was almost unrivalled, and acquaintance with the leading botanists and horticulturalists of Europe. It was then no matter for surprise that he should accept the position, even though the initial salary was small, and no official house was provided.
As the date of Sir William's appointment may be said to be the birth-day of the new development of Kew, it will be well to pause a moment and consider the position of botanical affairs in Europe at that time. The glamour of the Linnaean period had faded, and the Natural System of Classification of Plants initiated by De Jussieu had fully established its position, and had been worked into detail, taking its most elaborate form in the Prodromus Systematic Naturalis of Augustin Pyrame De Candolle. That great luminary of Geneva died in this very year of 1841, leaving his work, initiated but far indeed from completion, in the hands of his son Alphonse. In England, Robert Brown was in the full plenitude of his powers, and in possession of the Banksian herbarium was evolving out of its rich materials new principles of classification, and fresh morphological comparisons. In fact morphology was at this time being differentiated from mere systematic as a separate discipline. Nothing contributed more effectively to this than the publication of Die Botanik als inductive Wissenschaft, by Schleiden, the first edition of which appeared in 1842: for in it development and embryology were for the first time indicated as the foundation of all insight into morphology. But notwithstanding the great advances of this ​period in tracing natural affinities, and in the pursuit of morphological comparison, branches which would seem to provide the true basis for some theory of Descent, the Dogma of Constancy of Species still reigned. It was to continue yet for 20 years, and the most active part of the life of the first Director of Kew was spent under its influence.
Meanwhile great advances had been made also in the knowledge of the mature framework of cell-membrane in plants. Anatomy initiated in Great Britain in the publications of Hooke, Grew, and Malpighi, had developed in the hands of many "phytotomists," the series culminating in the work of Von Mohl. But it was chiefly the mere skeleton which was the subject of their interest. Eight years previously, it is true (1833), Robert Brown had described and figured the nucleus of the cell, and approached even the focal point of its interest, viz. in its relation to reproduction. But the demonstration of the cytoplasm in which it was embedded was yet to come. In fact, the knowledge of structure omitted as yet any details of that body which we now hold to be the "physical basis of life."
The period immediately succeeding 1841, was, however, a time pregnant with new developments. The study of protoplasm soon engaged the attention of Von Mohl. Apical growth was investigated by Naegeli and Leitgeb. The discovery of the sexuality of ferns, and the completion of the life-story by Bischoff, Naegeli, and Suminski led up to the great generalisation of Hofmeister. And thus the years following 1841 witnessed the initiation of morphology in its modern development. On the other hand, Lyell's Principles of Geology had appeared and obtained wide acceptance. Darwin himself was freshly back from the Voyage of the "Beagle," while Sir Joseph Hooker, then a young medical man, was at that very time away with Ross on his Antarctic voyage, and shortly afterwards started on his great journey to the Himalaya. These three great figures, the fore-runner of Evolution, the author of the Origin of Species, and Darwin's first adherent among biologists, were thus in their various ways working towards that generalisation which was so soon to revolutionise the science of which Kew was to become the official British centre. Well may we then regard ​this date, and the event which it carried with it, as a nodal point in the history of botany not only in this country, but also in the world at large.
The urgent necessity for such an official centre as Kew now is was patent in the interests of the British Empire. The need of it had already been clearly before the minds of the Parliamentary Commission, appointed a few years before, with Dr Lindley as chairman, to report upon the question of the retaining of the Botanic Gardens at Kew. The report contained the following passage which, while it formulates an ideal then to be aimed at, summarises in great measure the activities of the present establishment at Kew. "The wealthiest and most civilised country in Europe offers the only European example of the want of one of the first proofs of wealth and civilisation. There are many gardens in the British colonies and dependencies, as Calcutta, Bombay, Saharunpore, the Mauritius, Sydney, and Trinidad, costing many thousands a year: their utility is much diminished by the want of some system under which they can be regulated and controlled. There is no unity of purpose among them; their objects are unsettled, and their powers wasted from not receiving a proper direction: they afford no aid to each other, and it is to be feared, but little to the countries where they are established: and yet they are capable of conferring very important benefits on commerce, and of conducing essentially to colonial prosperity. A National Botanic Garden would be the centre around which all these lesser establishments should be arranged: they should all be placed under the control of the chief of that garden, acting with him, and through him with each other, recording constantly their proceedings, explaining their wants, receiving supplies, and aiding the mother country in everything useful in the vegetable kingdom: medicine, commerce, agriculture, horticulture, and many branches of manufacture would derive considerable advantage from the establishment of such a system....From a garden of this kind Government could always obtain authentic and official information upon points connected with the establishment of new Colonies: it would afford the plants required on these occasions, without its being necessary, as now, to apply to the officers of private ​establishments for advice and help....Such a garden would be the great source of new and valuable plants to be introduced and dispersed through this country, and a powerful means of increasing the pleasures of those who already possess gardens: while, what is far more important, it would undoubtedly become an efficient instrument in refining the taste, increasing the knowledge, and augmenting the rational pleasures of that important class of society, to provide for whose instruction is so great and wise an object of the present administration."
Such were the surrounding conditions, and such the aims of Sir William Hooker when he took up the duties of Director of the Royal Gardens. He was, however, given no specific instructions on entering office. He therefore determined to follow the suggestions of Dr Lindley's Report, and in the carrying of them out he had powerful support, both official and other. The original area of the Garden, apart from the Pleasure Grounds and the Deer Park, was small; when first taken over from the Lord Steward's Department by the Commissioners of Woods and Forests, it extended only to about 18 acres, and the Chief Commissioner, Lord Duncannon, was strongly opposed to their enlargement, or to further expenditure upon them. It required methods of diplomacy, as well as determination and energy, not always to be found among scientific men, to carry into effect the scheme laid down in the Report, and success came only slowly. In 1842 additional ground was taken in from the Pleasure Grounds, so as to afford an entrance from Kew Green, now the principal gate of the Garden. In 1843 there were added 48 acres of Arboretum, including the site of the Great Palm House. This was commenced in 1844, and was followed in 1846 by the Orchid House. In 1848 the old storehouse for fruit (close to the fruit garden of the old Palace, now the site of the Herbaceous Ground), was converted into a Museum of Economic Botany, the first of its kind to be established. It was in part furnished by the collections which Sir William had brought with him from Glasgow. It now stands as Museum No. II. In 1850 the Water-Lily House was built, and in 1855 the long house for Succulents. Meanwhile, in 1853, an official house had been found for the Director, while another Crown house adjoining ​Kew Green was handed over for the growing herbarium and library. These, which were in the main if not indeed altogether the private property of the Director, had up to this time been housed in his private residence. Now they found more convenient accommodation, where they would be more accessible for reference, in a building belonging to the establishment. In 1857 the Museum No. I. was opened. For long the collections had exceeded the space in the older Economic Museum (No. II.). This was, however, retained for the specimens belonging to the Monocotyledons and Cryptogams, while those of the Dicotyledons were arranged in the new and spacious building of No. I. In 1861 a reading-room and lecture-room for gardeners was opened, and in 1862 the central portion of the great range of the Temperate House was completed from plans approved in 1859. The wings which now complete the original design were added many years afterwards. In 1863 the old Orangery was disused as a plant-house, and diverted to the purpose of a Museum for Timbers, chiefly of colonial origin. It is now known as Museum No. III. The above may serve as a summary of the more important material additions to the Kew establishment, made during the life of Sir William Hooker. It will be clear that his activity must have been unceasing, in working towards the ideal sketched in the report of Dr Lindley. His efforts never abated till his death in 1865, in the 81st year of his age. The establishment of Kew has developed further as years went on. But as he left it, the essentials were already present which should constitute a great Imperial Garden. Truly Sir William Hooker may be said to have been the maker of Kew, if regard be taken merely of the material establishment.
In no less degree may he be held to have been the maker of Kew in respect of its scientific collections, its methods, and its achievements. To these his own untiring activity contributed the driving force, while his wide knowledge, and ready apprehension of fact gave the broad foundation necessary for successful action. But as the period of development of Kew in these respects was but the culmination of the work already initiated in Glasgow, it will be well to review Sir William Hooker's scientific ​achievements over the whole of his professional career, including the Glasgow period together with his later years at Kew.
Taking first the living collections, he had already shown at Glasgow, where the opportunities were more limited than at Kew, a singular success in securing additions to the plants under cultivation. This is now reflected more clearly in the lists which were published from time to time than in any actual specimens still living after the vicissitudes of cultivation of 70 years; though it is not improbable that some of our older specimens date from his period of office. The current floristic serials, many of them produced and even personally illustrated by himself, also form a record of the novelties from time to time secured. This rapid growth of the Glasgow garden has already been noted, and the large number of the plants introduced under his influence. It only required the same methods to be put in practice in the larger sphere of action of the metropolis to ensure a similar, though a far greater result at Kew. Moreover, the official position which he there held as Director, gave an increasing obligation to meet his wishes on the part of foreign and colonial gardens, and other sources of supply. Notable among the many other living collections that resulted was the series of Ferns, already a subject of his detailed study while at Glasgow. In its maintenance and increase he was ably assisted by the Curator, Mr John Smith, himself no small a contributor to the systematic treatment of the Ferns. Hooker's aim was, however, not to forward the interests of any special group of plants, but to make the collections as representative as possible. This is clearly reflected in the various character of the plant-houses successively built at his instigation, and remaining still to testify to the catholicity of his views.
In the days at Glasgow, Sir William had already made his private museum ancillary to the living collections, in his endeavour to demonstrate the characters of the vegetable world. This line of demonstration he further developed after his removal to Kew, and the results, together with later additions, but with methods little changed, are to be seen in the splendid museums of the Gardens at the present time. The specimens were from the first mainly illustrative of Economic Botany, such as are of ​service to the merchant, the manufacturer, the dyer, the chemist and druggist, and the physician: or to artificers in wood and in textiles. But the interests of the scientific botanist were not forgotten, while a special feature from the first was the portrait gallery of the leaders in the subject. Thus the museums which he initiated, and were indeed the first Museums of Economic Botany ever formed, are now not the least interesting and certainly among the most instructive features of Kew. But the centre of the Garden for reference and for detailed study is now the herbarium and library, housed in the large building near to the entrance from Kew Green. To those familiar with that magnificent mine of accumulated learning as it now stands, it may be a surprise to hear that it has grown in the course of less than 60 years out of the private collections of Sir William Hooker, and of his friend Bentham. The story of it may be gathered from the sketch of the Life and Labours of the First Director, published by Sir Joseph Hooker in the Annals of Botany in 1903, a work to which I have been largely indebted for the materials for this lecture. The Hookerian herbarium and library were already extensive before it was removed from Glasgow. When the new Director of Kew took up his appointment, neither books nor a herbarium were provided for him: but he was well equipped with those of his own. They were at first lodged in his private house, till in 1853 he moved into the official residence. But the latter did not afford the accommodation for them which the Government had guaranteed. They were therefore placed in a building adjacent to the Botanic Garden. It was further agreed, on condition that the herbarium and library should be accessible to botanists, that he should be provided with a scientific herbarium Curator. Four years afterwards the Royal Gardens came into possession, by gift, of the very extensive library and herbarium of G. Bentham, Esq., which was second only to Hooker's own in extent, methodical arrangement, and nomenclature; and it was placed in the same building. The two collections in considerable degree overlapped, being derived from the same sources. But one great difference between them was that Bentham confined his herbarium to flowering plants, while Hooker's rapidly grew to be the ​richest in the world in both flowering and flowerless plants. Finally after his death it was acquired by purchase for the State in 1866, together with about 1000 volumes from his library, and a unique collection of botanical drawings, maps, MSS., portraits of botanists, and letters from botanical correspondents, which amounted to about 27,000. These were the prime foundations of the great herbarium and library now at Kew. Great additions have since been made by purchase and by gift, and the building has been repeatedly extended to receive the growing mass of material. But for all time the character and individuality of the collections will remain stamped by the personality of those two great benefactors, Bentham and the first Hooker.
Sufficient has now been said to indicate that Hooker's work was that of a pioneer, in providing the material foundation necessary for the further study of the science, not only in this country, but also in the furthest lands of the Empire. He supplied a coordinating centre for botanical organisation in Britain, and for that service he has earned the lasting gratitude of botanists. It remains to review his own published works, and base upon them some estimate of his more direct influence upon the progress of the science. We shall see that in this also his work was largely of that nature which affords a basis for future development. It was carried out almost entirely under pre-Darwinian conditions. He was pre-eminently a descriptive botanist, who worked under the influence of the current belief in the constancy of species. But his enormous output of accurate description and of delineation of the most varied forms, has provided a sure basis upon which the more modern seeker after phyletic lines may proceed.
There have been few if any writers on botanical subjects so prolific as Sir William Hooker, and probably none have ever equalled him in the number and accuracy of the plates which illustrated his writings. Sir Joseph Hooker estimates the number of the latter at nearly 8000, of which about 1800 were from drawings executed by himself. The remainder were chiefly from the hand of Walter Fitch, who acted as botanical limner to Sir William for thirty years, showing in the work fidelity, artistic ​skill and extraordinary rapidity of execution. The numbers quoted give some idea of the magnitude of the results.
For the purpose of a rapid review of the chief writings of Sir William's later years, they may be classified under three heads, viz. (1) Journals, (2) Floristic works, and (3) Writings on the Filicales. Taking first the Journals, one of the most remarkable features about them is the apparent variety and number of the enterprises on which Sir William engaged: this is, however, explained when they are pieced together as they will be found below. His connection during 45 years with large and growing gardens, into which the most varied living specimens were being drafted in a constant stream, put him in possession of a vast mass of facts, detached, but needing to be recorded. The materials were thus present for that type of publication styled a Botanical Miscellany. The majority of the serials which he edited took this form, and though published under various titles, dictated in some measure by the source of their publication, more than one of them was a mere continuation of a predecessor under a different title. The first of them appeared under the name of the Exotic Flora, in three volumes (1823-7), with 232 coloured plates illustrating subjects from the Gardens of Glasgow, Edinburgh, and Liverpool. But owing to his taking up in 1827 the editorship of the Botanical Magazine, then in a critical position, the Exotic Flora ceased, and its materials swelled the pages of the more ancient serial, with which he was connected till his death.
To those not intimately acquainted with the other serials edited by Sir William, their relations are difficult to trace. But Sir Joseph Hooker has given their titles in series, with their dates, as follows:
Botanical Miscellany. 3 vols. 1830-33.
Journal of Botany. 1 vol. 1834.
Companion of the Botanical Magazine. 2 vols. 1835-36.
Jardine' s Annals of Natural History. 4 vols. 1838-40.
The Journal of Botany (continued). Vols. II.-IV. 1840-42.
The London Journal of Botany. 7 vols. 1842-48.
The Companion of the Botanical Magazine. (New Series. 1845-48.)
​London Journal of Botany and Kew Gardens Miscellany. 9 vols. 1849-57.
From this list it appears that throughout a long term of years, though under varying titles, the stream of information gathered chiefly through garden management was edited and published, taking the form of 28 volumes, with 556 plates.
The "Floristic" works of Sir William Hooker began with the second edition of Curtis's Flora Londinensis, in five folio volumes, upon which he worked from 1817 to 1828. He contributed a large proportion of the plates from his own drawings, while the descriptions throughout (excepting those of the plates on Algae and Fungi by R. K. Greville) were enlarged, and rewritten by him. He was in fact the real author of the work, which, however, was so badly edited—even the letter-press was not paged—that citation of it was impossible, and it never took its proper place as a scientific work. Sir Joseph Hooker points out that the second edition was not properly styled Flora Londinensis, since it included many species which are not indigenous anywhere near London. But these were the lapses of the editor, not of the author and artist. Minor works were the accounts of the plants collected on Parry's and Sabine's Arctic voyages (1823-28), but the Flora Boreali Americana was a more important undertaking. It appeared as two quarto volumes (1829-40), in which 2500 species were described with numerous illustrations. It was based on the collections of various travellers, and included ferns and their allies. In 1830 came the first edition of the British Flora, a work which was continued through eight editions, the last being in 1860, and it contained 1636 species. The botanical results of Beechey's voyage in the "Blossom" to the Behring Sea, the Pacific Ocean, and China were produced jointly with Dr Walker-Arnott in 1830-41, as a quarto volume, with descriptions of about 2700 species, and notable for the diversity of the floras included. In 1849 the Niger Flora appeared, dealing with the collections of Vogel on the Niger expedition of 1841. But the most remarkable of all these floristic works was the great series of the Icones Plantarum. It was initiated in 1837 for the illustration of New and rare plants selected from the Author's Herbarium, ​and was continued by him till his death in 1865. Owing to the munificence of Bentham's bequest to the Kew Herbarium for its continuance and illustration, it remains still as the principal channel for the description and delineation of new and rare plants from the Kew Herbarium. The fact that the number of the plates is now about 3000 gives some idea of the magnitude of this work, which was started by Sir William Hooker in the later days of his Glasgow professorship.
It might well be thought that the production of the works already named would have sufficed to occupy a life-time, especially when it is remembered that they were produced in the intervals of leisure after the performance of the official duties of a professor, and later of the Director of the growing establishment at Kew. But there still remain to be mentioned that noble series of publications on the Filicales, which gave Sir William Hooker the position of the leading Pteridologist of his time. The series on ferns began with the Icones Filicum (1828-31) in two folio volumes, with 240 coloured plates by R. K. Greville, the text being written by Hooker. The same authors again cooperated in the Enumeratio Filicum (1832), a work projected to give the synonymy, citation of authors, habitat, and description of new and imperfectly known species. But it only extended to the first 13 genera, including the Lycopodineae, Ophioglosseae, Marattiaceae, and Osmundaceae, and was then dropped. Here may be conveniently introduced a number of volumes, which were for the illustration of ferns, but not systematically arranged. They were issued from time to time, and collectively give a large but not a coordinated body of fact. They were, the First Century of Ferns, issued in 1854; the Filices Exoticae in 1859; a Second Century of Ferns in 1861; British Ferns also in 1861, and Garden Ferns in 1862.
There still remain to be mentioned three great systematic works on ferns, each of which is complete in itself, viz. the Genera Filicum, the Species Filicum, and the Synopsis Filicum. The first of these was the Genera Filicum (1838-40), a volume issued in parts, royal octavo, with 126 coloured plates illustrating 135 genera. It goes under the joint names of Francis Bauer and Sir William Hooker, the latter being described on the ​title-page as Director of Kew. But the preface is dated May 1, 1838, from Glasgow, and it was printed at the University Press. The title-page further states that the plates were from the drawings of F. Bauer, but Sir Joseph Hooker points out (l.c. p. cviii), that "of the whole 135 genera depicted I think that 78 are by Fitch." Sir William in the preface states that "The plates have all been executed in my own residence, and under my own eye, in zincography, by a young artist, Walter Fitch, with a delicacy and accuracy which I trust will not discredit the figures from which they were copied." The result is one of the most sumptuous volumes in illustration of a single family ever published. After 70 years it is still the natural companion of all Pteridologists. At its close is a synopsis of the genera of ferns, according to Presl's arrangement, which Sir William describes as "the most full and complete that has yet been published." But in the preface he remarks that Presl "has laid too much stress on the number and other circumstances connected with the bundles of vessels in the stipes, which in the Herbarium are difficult of investigation." This is a specially illuminating passage for us at a time when anatomical characters are becoming ever more important as phyletic indices. It shows that readiness of diagnosis was for him a more important factor than details of structural similarity.
In the preface to the Genera Filicum Sir William says, he "would not have it to be understood that the Genera here introduced are what I definitely recommend as, in every instance, worthy of being retained....A more accurate examination of the several species of each Genus, which are now under review in the preparation of a Species Filicum, will enable me hereafter to form a more correct judgement on this head than it is now in my power to do." The five volumes of the Species Filicum thus promised, appeared at intervals from 1846 to 1864. The work is briefly characterised by Sir Joseph as consisting of "descriptions of the known Ferns, particularly of such as exist in the Author's Herbarium, or are with sufficient accuracy described in the works to which he has had access, accompanied by numerous Figures. This which will probably prove to be ​the most enduring monument to my father's labour as a systematist and descriptive pteridologist, is comprised in five 8vo volumes, embracing nearly 2500 species, with 304 plates by Fitch, illustrating 520 of these. It occupied much of the latter eighteen years of his life, the last part appearing in 1864." The work is a most extraordinary mine of detailed information. It is a condensed extract from his own unrivalled Herbarium of Ferns, with exact data of distribution, and collectors' numbers. Probably no family so extensive as this has ever been monographed by a single hand with such minuteness and exhaustive care. It is the classic book of reference in the systematic study of ferns. But as indicated in the preface to the Genera, the judgement as to which genera are "worthy of being retained" had been exercised. The result was the merging of a number of the genera of Presl, and others, into neighbouring genera. Though this was somewhat drastically done in the Species Filicum, it comes out more prominently in the work upon which he entered in the very last months of his life, viz. the Synopsis Filicum. This work was published in 1868 as an octavo volume, with 9 coloured plates, containing analyses of 75 genera. Sir Joseph tells us (l.c. p. 117) that "Upon this work my father was engaged up to a few days before his decease, and 48 pages of it in print were left on his desk, together with the preface and much matter in manuscript. After full consideration it appeared to me that, with the material in hand, the aid of the Species Filicum completed only three years earlier, and of the Fern Herbarium in perfect order, and named according to his views, a competent botanist should find no great difficulty in carrying on this work to its completion. Such a botanist I knew my friend Mr Baker to be, and also that he had made a study of Ferns, and accepted my father's limitations of their genera and species. I therefore requested that gentleman to undertake the work, which to my great satisfaction he has done. The Synopsis Filicum contains 75 genera, and about 2252 species, inclusive of Osmundaceae, Schizaeaceae, Marattiaceae, and Ophioglossaceae, which are not included in the Species Filicum." This work summarised the Pteridological results of Sir William Hooker's life. The total number of plates of ferns published by him is ​about 1210, embracing 1267 species, of which about 250 appeared under the joint authorship of Dr Greville and himself. These figures are in themselves sufficient evidence of the extent of his Pteridographic work.
It has been noted that the number of genera in the Genera Filicum was 135, maintained approximately according to the limitations of Presl in his Tentamen Pteridographiae: allowance has, however, to be made for 23 genera of Parkeriaceae, Schizaeaceae, Osmundaceae, Marattiaceae, Ophioglossaceae, and Lycopodiaceae, which were omitted in the Tentamen. But in the Synopsis Filicum there were only 75. It is true that the three genera of Lycopodiaceae were excluded also from the Synopsis, but still there is the wide discrepancy between 132 of Presl's genera as against 75 in Hooker's Synopsis. This at once indicates a salient feature of his method. He merged a large number of genera, ranking many of the smaller ones as subgenera under the more comprehensive headings. Doubtless the reasons for this were various. One was his mistrust of anatomical data, which it must be confessed Presl put too much in the fore-front. The very first sentence of the Tentamen runs thus "Vasa plantarum principale signum esse ex eo patet, quod exinde primaria divisio omnium plantarum exstitit." But occasionally Sir William explained his reason in a specific case. Thus in the question of Kunze's sub-genus Plagiogyria of the genus Lomaria, which Mettenius had raised to the dignity of a distinct genus, he explained his reasons for merging it into the genus Lomaria. Mettenius had laid stress upon various characters, but especially on the oblique annulus as distinctive. On this Hooker remarks "even should the capsules in all the species referred to Plagiogyria prove to be helicogyrate, yet the habit and sori are so entirely in accordance with true Lomaria that, unless the student has the opportunity of examining very perfect specimens, or unless he examines the structure of the annulus of the very minute capsules under the high power of the microscope, the genus cannot be identified. Kunze only proposed to form a group or section under the name of Plagiogyria, but even that would be found inconvenient to retain in a work whose main object is to assist the tyro in the verification of genera and ​species: and natural habit is often a safer guide than minute microscopic characters." Thus we see that in his method convenience of diagnosis is put before the use of important structural characters. I have recently found reason to uphold the opinion of Mettenius on this point, and to confirm Plagiogyria as a substantive genus.
Similarly, the genera Lophosoria and Metaxya will have to be detached from Alsophila: Prantl removed Microlepia from Davallia into his new family of the Dennstaedtiinae, where they are related with Patania (Dennstaedtia), which Hooker had merged into Dicksonia. Goebel also has detached Hecistopteris which Hooker had placed in Gymnogramme, and has placed it with the Vittarieae. These are all examples of the way in which further study is tending to reverse the excessive merging of genera, which Hooker carried out in the interest of diagnostic convenience.
The general conclusion which we draw from contemplating Sir William Hooker's work on the systematic treatment of ferns is that it was carried out consistently to the end under the influence of the current belief in the Constancy of Species. The methods were not phylogenetic, as they have since become under the influence of evolutionary belief. The problem seems to have been to depict and describe with the utmost accuracy the multitudinous representatives of the Filicales, and to arrange them so that with the least possible difficulty and loss of time any given specimen could be located and named. But the result is not to dispose them in any genetic order. Even the arrangement of the larger genera according to the complexity of branching of the leaves appears as a method of convenience rather than of genesis, and subsequent inquiry is tending to show that so far as such series really exist, they will require to be read in converse. Goebel, in his paper on Hecistopteris, remarks that "the systematic grouping of the Leptosporangiate Ferns, as it is at present, e.g. in the Synopsis Filicum, is artificial throughout; it is adequate for the diagnosis of Ferns, but it does not give any satisfactory conclusion as to the affinity of the several forms." He proceeds to say that "a thorough investigation, taking into account the general characters of form of both the ​generations, will be necessary before the naturally related groups, and their relations to one another, are recognised in the plexus of forms of the Polypodiaceae."
Such observations as these must not be understood in any sense of disparagement of the work of this great man. They are merely intended to indicate his historical position. The Origin of Species was, it is true, published some few years before the Synopsis Filicum. But we must remember that Sir William Hooker was already an old man. Few men over 70 years of age alter their opinions, and the labourer who had grown old under the belief in the Constancy of Species could not in a few brief years be expected to change the methods of thought of a long and active life. We must take Sir William Hooker as perhaps the greatest and the last of the systematists who worked under the belief in the Constancy of Species. Because we have adopted a newer point of view, and take into consideration facts and arguments which were never his, and come to different conclusions now, is no reason for valuing one whit the less the achievements of this great botanist.
His published work was just as much fundamental as was his official work. We have seen how he provided in Kew the means of indefinite development later, by constructing the coordinating machine with its collections and its libraries. In somewhat similar sense his publications were also fundamental. He did not himself construct. There is, I believe, no great modification of system or of view which is to be associated with his name. But in the wealth of trustworthy detail, recorded both pictorially and in verbal diagnoses, he has supplied the foundation for future workers to build upon, laid surely and firmly by accurate observation, and therefore durable for all time. One remark I may make as to the effect of his work on the trend of botanical activity in this country. We have noted that anatomy was not Sir William Hooker's strong point. He and many of his contemporaries did not pursue microscopic detail, and indeed seem to have avoided it. He was, however, a dominating botanical influence of the middle Victorian period. May we not see in these facts, combined with the extraordinary success of the systematic work carried on by himself, or under ​his guidance, a probable cause of that paralysis of laboratory investigation which ruled in Britain till the early seventies? British botany was at that time almost purely descriptive. The revival came within 10 years of the death of Sir William, and it is well to remember that the immediate stimulus to that revival was given by a botanist, who became later the Director of Kew, and was allied by marriage with Sir William Hooker himself. I mean, Sir William Thiselton-Dyer. The stimulus had its result in the active development of anatomical and physiological study of plants, as we see it in this country to-day. For a time the swing of the pendulum in this direction was too extreme and exclusive. I remember very well an occasion when Sir Joseph Hooker said to me, "You young men do not know your plants." And it was true, though it may be added that few indeed, at any time, knew them in the full Hookerian sense. A saner position is gradually being attained. But even now the systematic study of Angiosperms receives far too little attention among us, and is an almost open field for the young investigator.
I would conclude with one word of advice, which naturally springs from contemplation of a life-work such as Sir William Hooker's. We sometimes see wide-reaching phyletic conclusions advanced by writers who we know have not specific knowledge of the groups in question. Let us learn from Sir William the importance of specific knowledge. It is only on such a foundation that sound phyletic argument can proceed. Let us always remember that it is better to carry out sound work on species, as he did, without theorising on their phyletic relations, than to promulgate phyletic theories without a sufficient specific knowledge of the families themselves. The former will probably be lasting work, the latter runs every chance of early refutation.
Under the most favourable circumstances analytical work is as a rule more durable than synthetic. Sir William Hooker's contributions fall chiefly under the former head, and will be found to have a corresponding element of durability.