George Arnott Walker-Arnott, 1799 - 1868

by Brian Stevenson
last updated December, 2010

George A. Walker-Arnott was Professor of Botany at the University of Glasgow, Scotland, during the mid-1800s, and made numerous significant contributions to that field. Toward the end of his life, he focused his energies on studying diatoms. Arnott left behind his imprint in the naming of countless species of plants and diatoms, and specimens of both plants and diatoms that can still be found in museums throughout the world. The National Botanic Garden of Belgium currently holds about 2000 tubes of Arnott’s diatom gatherings. The Royal Botanic Garden of Edinburgh also holds an extensive collection of Arnott’s diatom slides and gatherings. Julien Deby reported in 1891 that his collection contained 1100 diatom slides that had been prepared by Arnott, plus 300 tubes of unmounted, cleaned material. Thomas Rylands and Robert Greville also acquired many of Arnott’s microscope slides. Deby’s, Rylands’ and Greville’s collections, including their Arnott slides, were later acquired by the British Museum. Other early diatom biologists, such as Arthur S. Donkin, also wrote of owning slides by Arnott. Thomas Curties donated 50 diatom slides, including several mounted by Arnott, to the Quekett Microscopical Club in 1871. Doubtless, many other friends and colleagues acquired slides made by Arnott, which have since found their ways into the cabinets of diatom biologists and slide collectors (Figure 1).

Figure 1. Examples of microscope slides prepared by George A. Walker Arnott. All are strews of mixed species. Arnott’s handwriting is distinctively untidy, but these would have been samples for botanical studies, not for show or sale. Close-up views of two labels are shown below the slides, to aid collectors with identification of Arnott’s handwriting. The as-yet unknown microscopist “JR” added his own labels to one of these slides. The right-most slide bears an additional, oval label from Wheeler/Watson, almost definitely due to their re-selling of this slide. Further examples of Arnott’s slides can be seen on-line at the Royal Botanic Garden Edinburgh web site ( and in print in Nuttall, 2009, Quekett Journal of Microscopy 41:45.


Figure 2. Two magnified views of Arctic diatomaceae from Port Kenedy, Canada (the leftmost slide in Figure 1, above), using darkfield illumination. This appears to be typical of an Arnott preparation, being a strew of mixed species. His label notes the presence of Tricer(atum) arcticum, presumably the large triangular diatoms seen in both of these images. This is thicker than the other diatom species present, and focuses in a different field. Frederick Lang reported that “in the very last year of the late Dr. Arnott's life, I heard him say that were he to commence a fresh collection of diatomaceae he would admit none but perfectly pure and unmixed gatherings into his cabinet”.


Possibly triggered by advances in microscope optics, the 1800s saw widespread enthusiasm for diatom research. As Arnott pointed out, there were two directions to this diatom mania. Naturalists, such as Arnott, used microscopes to investigate the biology of diatoms and other microscopic organisms. Others took advantage of the fine structures of diatoms for use as “test objects”, by which they could examine the quality of their lenses. Arnott took exception to the latter. A. Mead Edwards wrote “I am reminded of what my good friend, the late Dr. Walker-Arnott, once pointed out in his vigorous manner to me - that there are microscopists and naturalists. . . I may, I think, with benefit to many, quote Dr. Arnott's remarks on this subject. I had written to him, introducing myself as a brother microscopist, hoping thereby to secure his good will. His reply was, ‘I am afraid you mistake me and my pursuits. So far from being a microscopist, I wage war with the fraternity, and I have on that account refused to become a member of the Microscopical Society of London. I consider that a microscopist looks on everything as subservient to the microscope, and that whatever he sees and which appears distinct to the eye, he thinks ought to be described or figured as distinct. I am, on the other hand, a naturalist, a botanist in particular, and use the microscope, simple or compound, as a necessary evil, merely to enable my eyes to see better minute structures; but whether these differences amount to specific or generic importance, or are only peculiar forms of one species, is the result of analogy, a mental process which can only be attained by a training in botany in all its branches, for many years. A microscopist is to a naturalist what a gardener is to a botanist. In general, microscopists are amateurs carrying on some other profession, and not having their attention devoted uninterruptedly to natural history. In fact few microscopists know anything of the laws of natural history for genera or species; and therefore the species created by them are in general worthless’. Unfortunately these words, which were penned twenty years ago, apply just as well at the present day. Most of our microscopists are not naturalists, but fortunately many of our naturalists now are microscopists. Of course a botanist who grows his own plants, and is his own gardener, will know more concerning their habits and peculiarities than he would if he only studied such specimens as were brought to him by a collector.

Francesco Castracane degli Antelminelli further elaborated on Arnott’s comments in the first two paragraphs of the introduction to his Report on the Diatomaceae collected by H. M. S. Challenger during the years 1873-1876, “The extreme difficulty of acquiring an adequate knowledge of Diatoms, owing to their small size and the impossibility of following attentively and registering every stage of their development under the microscope, renders the greatest care necessary in the observation of every phenomenon presented by the living species. As, however, the making of such useful observations is entirely fortuitous, the majority of the earlier investigators are found almost exclusively to have been satisfied with making a mere record of the different types occurring in their preparations, the most of which were purchased from traders in this department of microscopy, who vied with each other in procuring new or rare forms.
The eagerness of these observers to possess such novelties, with the view, in many cases, of designating new species by their own names, along with the too hasty work of the first discoverers of Diatoms, and especially of Ehrenberg, had the effect of introducing a nomenclature that was misleading, and of causing a confused synonymy that has been justly designated the opprobrium of the science. Against the continuance of this state of things Professor Walker Arnott raised an authoritative voice, going so far even as to declare that any researches relating to types found in the stomachs of molluscs and fishes, or obtained from marine soundings, were altogether useless. By thus acting it cannot be doubted that this naturalist exceeded all reasonable limits, but it is to be borne in mind that he did so with the view of putting a restraint on those who were too careless in conducting their investigations.

Figure 3. Professor George A. Walker Arnott, circa 1860.


The life of George Arnott was well summed up in the obituary address that his colleague Hugh Cleghorn presented to The Botanical Society (Edinburgh):

George Arnott Walker-Arnott was born at Edinburgh on the 6th February 1799, but his early years were chiefly spent at Edenshead and Arlary, on the borders of Fifeshire and Kinross. He attended the parochial school at Milnathort when at Arlary, and also received instruction from the tutor of the sons of Mr. Cheape of Wellfield. He was not considered a quick boy, partly owing to his modest, retiring disposition, but he was a persevering student; and when the subject specially interested him, he sifted it to the bottom, an excellent memory enabling him to retain what he learned. His docile, kind disposition, and his earnestness in study, made him a great favourite with his teachers; but "he took little or no part," writes Dr Wight, "in the wilder school sports, and but little more in the quieter ones."

In the year 1807 he went to the High School of Edinburgh, where he was the pupil of Mr. Ritchie and Mr. Pillans. Among his contemporaries may be mentioned Professor Christison; Mr. Mark Sprot of Garnkirk; Mr. David Syme, Sheriff of Kinross; Dr Robert Wight, F.R.S.; and Dr Wm. Jameson, surgeon, Professor of Natural History at Quito. He was in the habit of carefully registering in a note-book the career of his school-fellows, in whose fortunes he cherished through after life a deep and abiding interest.

Mr. Arnott entered the Arts Classes of the Edinburgh University in 1813, and obtained a distinguished place both in languages and in mathematics, attracting by his eminence in the latter study the special notice of Sir John Leslie and Professor Playfair. It may be mentioned, as a proof of his mathematic and algebraic attainments, that while a pupil of Sir John, he was in the habit of revising his works and calculations for the press; and that two papers written by Arnott on mathematical subjects, while he was still a student in arts, appeared in Tilloch's Philosophical Magazine. These are "Observations on the Solution of Exponential Equations," May 1817, and a "Comparison between the Chords of Arcs employed by Ptolemy and those now in use," Nov. 1818.*

(footnote: * Sir John Leslie, in speaking of young Arnott, was accustomed to say that botany had spoiled a first-rate natural philosopher.)

With regard to his college life, Mr. Isaac Bayley, W.S., his cousin, and one of his earliest friends, writes, "Such as the boy was, the man became. At the High School and College the same persevering study characterised him, and he equally became the favourite of his teachers and professors, and avoided mixing much with his fellow-students. I well remember how difficult it was to get him to join any social or even family party."

He took the degree of A.M. in 1818, and after a further period of professional study for the bar, was admitted a member of the Faculty of Advocates in 1821. But law was an uninteresting subject to him, and he soon relinquished the legal profession. He had a dislike to public speaking, and only appeared in his advocate's gown three times. His father, Mr. David Walker-Arnott, died in 1822, when the property of Arlary, near Kinross, fell to him.

His attendance on the lectures of Professor Jameson early imbued him with a love for the study of natural science, especially of mineralogy; but the attractions of botany, which, he remarked, deals with lighter and more portable materials, subsequently prevailed, and it speedily became his absorbing pursuit. The lectures of Mr. John Stewart, an extra-academical lecturer in Edinburgh, developed his relish for this branch of study. He attended his course in 1817 and 1818, being associated in the latter year with Dr Greville in the Cryptogamic Class. Dr Wight writes, "Here it was our friendship began, in a friendly rivalry in the formation of our herbaria." His love for botany was subsequently converted into a life-long passion by his visits to France in 1821 and 1825, and his intercourse with the great French botanists, whose lectures and herbaria he frequented, and whose botanical excursions he joined.

Lady Hooker gives the following account of his intercourse with the late Sir W. Hooker, "Dr Arnott first came to Dr (Sir Wm.) Hooker's house during the summer course of lectures in 1821, bringing a letter of introduction from Dr Greville, who had made our acquaintance in Suffolk about a year previously. Dr G. was then applying for the botanical chair in Glasgow, and told us so, being ignorant that Dr Hooker had been appointed (on Sir Joseph Banks' recommendation) only a few days before. The excursion of students to Loch Lomond was soon to take place, and Arnott joined it, and continued always to make one of the party to Ben Nevis, or Staffa, or the Grampians, for many subsequent years. His taste for science became so confirmed by his intercourse with Dr Hooker, that he more and more devoted himself to it, though his parents greatly regretted his abandonment of the legal profession, to which he had been brought up. But the possession of the herbarium commenced in Glasgow by the gift of many duplicates from Dr Hooker's collection, and to which constant additions were made during Dr A.'s visits (and he was seldom absent six months at a time), worked like a spell in binding him to botany. I used to sit by, and name the specimens to dictation, thus expediting the work." Many of the herbarium specimens bear Lady Hooker's handwriting.

In 1821, immediately after passing advocate, Mr. Arnott went to France, and for two months worked hard in the late Baron Delessert's herbarium, then kept by Achille Richard and Guillemin, and also in the herbarium at the Jardin des Plantes. "When at Paris," he wrote, "I had the good fortune to make a botanical excursion with old Jussieu (author of the 'Genera Plantarum), the last he ever made. His son, Adrien de Jussieu (now also dead), took the management of the class. It was to the Etang de St Gracieu we went, and we slept all night in the neighbourhood."

One of his earliest botanical papers, "On some Mosses from Rio Janeiro," written in French, appeared in a Paris journal in 1823. Soon afterwards, in conjunction with Dr Greville, he published in the Wernerian Society's Transactions, three excellent memoirs, "Tentamen methodi muscorum; or, a new arrangement of the genera of mosses, with characters, and observations on their distribution, history, and structure."This was followed in 1825 by the "Nouvelle Disposition methodique des especes de mousses," contained in vol. ii. of "Memoires de la Societe d'Histoire Naturelle de Paris."

In 1825 he returned to Paris, when the kindness of Baron Delessert again gave him the opportunity of studying in his rich herbarium. Here he examined the collection of Palisot de Beauvois, and was enabled to make out many of his hitherto doubtful species of mosses. During this stay in Paris, he was requested by Mr. Bentham to visit him at Montpellier, and his partiality for botanical science induced him to comply. They met at Avignon, in the house of M. Requien, Director of the Public Garden, with whom and M. Audibert they botanised in the south of France, and made a tour to the Pyrenees, the results of which are recorded in an interesting series of letters to Dr Jameson, published in the "Edinburgh New Philosophical Journal," 1826-29.

Dr A. relates the following incident, "As to Hedwigia aquatica, few botanists would credit me should I say I gathered none of it, but fewer still will believe that I was at the pains to fill all my pockets and my hat as full as possible. While thus engaged, one of my companions came up, and assured me I had taken ' bien assez pour tous les botanistes en Europe.' 'Voila done pour l'Amerique,' was all I had time to answer, while I proceeded in my labours. There is certainly something very delightful in finding in quantities anything one has been long eager to lay hold of."

The friends next proceeded to Montpellier, and, in company with M. Delile, Professor of Botany, and M. Dunal, author of the monographs on the Anonaceae and Solanaceae, made excursions in the neighbourhood. The following curious fact is recorded in Dr Arnott's journal, " Every year a great quantity of wool is brought from Africa. It is landed at Pont Juvenal (called also Port Juvenal, for vessels come up this length to unload), and is spread out here to be bleached. Not a few seeds of African plants remain attached to the wool, and are thus sown; and the following years, when the ground for the wool is changed, they spring up. M. Delile, by searching diligently every fortnight or three weeks, has been so fortunate as to meet with several plants naturalised nowhere else in Europe, and some of them scarcely at all known to the botanist."

In the notes of his tour he institutes an interesting comparison between the botanical gardens of England and the Continent. "In France there are, in addition to the several botanical institutions in Paris, many smaller ones, also under Government, scattered through the country. I may instance those of Lyons, Strasburg, Montpellier, Toulouse, and Perpignan. When any of these receive the root of a new or rare species from another country, or its seeds, the year following either seeds or roots are transmitted to the Jardin du Roi at Paris; and also, when any new plant arrives there, it is as soon as possible disseminated through the smaller establishments of the provinces. The care and attention paid to the naming of the plants at the Museum prevents almost the possibility of an error, and thus in the Government institutions in the country the species is found well determined."Prats de Mollo is mentioned as one of the best points for a botanist's residence in the East Pyrenees. In the herbarium of M. Xatard at this place, in that of M. Marchaut at St Beat, and in that of M. La Peyrouse at Toulouse, they examined the types of most of La Peyrouse's plants, and comments on them are entered in Arnott's journal.

The party proceeded through North Spain as far as Barcelona. Mr. A. then went to Geneva, and studied three months in De Candolle's herbarium, boarding with M. Seringe, who had charge of it. The narrative of the tour was brought to an abrupt conclusion, in consequence of Mr. Bentham, who accompanied Mr. Arnott, having published at Paris his "Catalogue des Plantes des Pyrenees et du Bas Languedoc," with a sketch of the whole journey.

In 1828 he visited Russia, and acquired during his residence there considerable knowledge of the Russian language. Mr. Barclay, whose daughter he afterwards married, had been settled as a merchant in St Petersburg, and Mr. Arnott was induced to accompany him on his return from a visit to Scotland. Mr. A. had given up the bar, and had no desire at the time to settle at Arlary, but was eager to enlarge his knowledge of botany, and to make the acquaintance of Fischer, Ledebour, and other botanists. About this time he was elected member of the Imperial Society of Natural History at Moscow.

In 1831 he was married to Miss Mary Hay Barclay of Paris, in Perthshire, and resided at Arlary from 1831 till 1845, when he built additional rooms expressly for the accommodation of his now extensive library and herbarium. The friendship and intercourse with Sir W. Hooker continued during the whole period of that eminent botanist's residence in Glasgow. He often visited him (Sir William) there, and occasionally afterwards at Kew. The excellent article, Botany, in the 5th volume of the "Encyclopedia Britannica," 7th edit., appeared from his pen in 1831, and at the time of its publication was the best purely English exposition of the natural system of botany.

From 1830 to 1840 Mr. Arnott was engaged, conjointly with Dr (Sir Wm.) Hooker, in publishing an account of the botanical collections of Captain Beechey's voyage to the Pacific and Behring's Straits. This work, executed with great care, furnishes interesting notices of countries then little known, such as the Sandwich and Loochoo Islands, California, &c.

"In the autumn of 1832," writes Dr Wight, "he most kindly and liberally volunteered to assist me in the preparation of my then contemplated 'Peninsular Flora of India,' an offer most thankfully accepted and acted upon." Dr Wight's furlough expired before the completion of the first volume, which Mr. Arnott edited and published after his friend's return to India. The Prodromus, which is in the hands of every botanist, renders a detailed notice unnecessary. It is thus mentioned in Hooker and Thomson's Introduction to the Flora Indica, "We have already characterised this work as the most valuable and able contribution to Indian botany which has ever appeared, and as one which has few rivals in the whole domain of botanical literature, whether we consider the accuracy of the diagnoses, the careful limitation of the species, or the many improvements in the definition and limitation of genera, and the higher groups of plants." One volume only was published, the progress of the work having been interrupted by Dr Wight's return to India in 1834. "After the publication of vol. i., so much poured in on Mr. A. from India, that although he could have got out a second volume, it would have been necessary to publish a large supplement to the first; and, besides, there was not sufficient sale to pay expenses, so no more was printed, although a vast deal was prepared, and ready for the press." (Dr. Wight.)

The herbarium of Mr. Arnott at Glasgow, being particularly rich in Indian plants, is especially valuable, as containing the materials from which the Prodromm Florce Peninsula Indice Orientalis was elaborated. It proved afterwards a most material benefit to the authors of the Flora Indica, who often applied to it on doubtful points.

In 1837, King's College, Aberdeen, conferred on Mr. Arnott the degree of LL.D. In 1839, he lectured in Glasgow for Sir W. Hooker, who was temporarily absent, on account of family affliction, and in 1845 he received the appointment of Professor of Botany in that University, when Dr. Balfour was transferred to Edinburgh. From 1825 to 1855 he was continually occupied in elaborate researches, the results of which were embodied in the works already mentioned, and in numerous contributions to the Transactions of learned societies. At the end of this memoir is an enumeration of his botanical writings, which will serve to indicate the extraordinary industry of our lamented friend.

It is a remarkable feature in the scientific work of Dr Arnott, that so much of it was done in conjunction with others; his single-hearted devotion to science was conspicuous in his cordial co-operation with men of different nations and temperaments, such as Sir William Hooker, Drs. Greville and Wight, Roper, and Nees Von Eseubeck.

The single-mindedness with which he gave up his time to any one desirous of information, was beyond all praise. He would spend hours of the night in elaborating the collections of foreign botanists, purely for the love of science. Indeed, any survey of what Dr. Walker-Arnott has done for the progress of botany, would be incomplete if it was confined to the notice of his published works, numerous and important though they are. Account must be taken of the spirit in which he worked, of the extent of the researches which he carried out, of the correspondence which he kept up, and of the aid and encouragement which he was ready to give to botanists visiting him, or consulting his herbarium. As a botanist, his careful habits of observation, and minute accuracy of description, render his works peculiarly valuable; and his reputation in this respect is quite as great on the Continent as in this country.

Professor Decaisne of Paris writes, " La mort inattendue du Dr. Walker Arnott est une perte reelle pour la science, et, je puis ajouter, pour les nombreux amis qui, en Angleterre et en France, ont e'te a meme d'apprecier sea excellentes qualites, comme homme et comme savant."

In 1846 Dr Arnott left Arlary, and took up his residence in Glasgow, where he entered upon the duties of the professorship to which he had been appointed the previous year. As a professor, he was much respected and esteemed by all the students who had any real interest in the work of the class; and he had the gratification of imbuing many youthful minds with a permanent love for his favourite study. Dr J. Lindsay Stewart, at present Conservator of Forests in the Punjab, was one of his distinguished students, and is now one of the most rising botanists in India.

In 1860, when editing and remodelling the eighth edition of the British Flora, he addressed two humorous letters in rhyme to Sir W. Hooker on Brambles and Hawkweeds, which are characteristic of his desire to keep down the number of doubtful species. In truth, his zeal for rigid specific distinction has been of great benefit to the student of botany.

Of late years he devoted himself specially to the study of diatoms, with which his capacity for minute investigation, and his unwearying patience of research, pre-eminently fitted him to deal. The diatomaceous collection fills three cabinets, and is the richest in Great Britain. Dr Arnott contributed numerous papers on diatoms within the last few years to the Microscopic Society's Journal and Transactions, but by far the greater portion of his observations were communicated in letters to his scientific friends in England, on the Continent, and in America. Amongst these may be mentioned Professor Dickie of Aberdeen; Mr. Carruthers, British Museum; Messrs W. Wilson and T. G. Rylands, Warrington; S. Roper, London; G. Norman, Hull; F. Kitten, Norwich; and Dr Lewis of Philadelphia. In 1866 he visited several of his correspondents in England, and also went to France, where he spent about ten days with his friend, M. de Brebisson, at Falaise in Normandy, all the time being constantly at work on diatoms.

For twelve months prior to his decease Dr Arnott's general health had evidently declined, and he was unable to take his accustomed exercise. At the commencement of the summer session be made an effort to resume with wonted zeal the labours of his class ; but it was obvious to all his friends that the effort was attended with great pain and much risk, and that the conscientious desire to discharge his duty was impelling him to overtask his strength. After a few days the writer, who had just returned from India, was requested to carry on the duties of the class, to which he gladly acceded. It was a pleasure to aid in time of need one from whom he had received valuable assistance in botanical research, and he was an inmate of Dr Arnott's house during the tedious and painful illness which proved fatal. Jaundice appeared in April, and remained prominent till his death on the 17th of June, in the seventieth year of his age. He was interred on the 20th at Sighthill Cemetery, near Glasgow, in the presence of a large number of friends, members of the senate, and students. Mrs. Arnott, three sons, and five daughters survive this distinguished botanist.

One of the trustees appointed is Dr Hooker, F.R.S., and it may be mentioned that after inspecting the valuable herbarium and library left by Dr Arnott, it was resolved to offer them to the Glasgow University, and it is hoped that they may thus become available to the nation. Dr Hooker remarks as follows, "During this inspection, I became strongly impressed with the great importance of the books and plants being kept together, as being portions of a whole, and the work of one mind devoted for half a century to one object - the promotion of botanical research. There is another point of view under which it appears to me to be a matter of great moment that the books and plants should not be dissociated, and this is, that both of them illustrate in a most remarkable manner the rise and progress of systematic and descriptive botany during the earlier part of the present century, during which period exotic botany first became a science properly so called. Under the latter point of view, these collections of books and plants possess a rare interest and value for a public and especially an educational institution, such as Glasgow University, to which the trustees are empowered to offer them at a fair valuation.

Cleghorn added a list of 69 books, chapters and articles published by Arnott, and a footnote that “A memorandum in Dr Arnott's handwriting gives the following dates:

Entered at College of Edinburgh, Nov. 1813.
Took degree of A. M. 1818.
Was admitted to the Faculty of Advocates, 1821.
Got degree of LL.D. from King's College, Aberdeen, 1837.
Appointed Regius Professor of Botany, Glasgow, 1845.
Fellow of Royal Society of Edinburgh, 1822.
Membre de la Society d'Histoire Naturelle de Paris, 1822.
Member of Wernerian Society of Edinburgh, 1822.
Member of Botanical Society of Ratisbon, 1824.
Fellow of Linnean Society of London, 1825.
Member of the Imperial Society of Natural History of Moscow 1829.
Member of the Royal Physical Society of Edinburgh, 1830.
Member of the Acad. Ca'sar Leopold Nat. Curiosorum, under the cognomen of "Sibbald," 1834.
Member of Botanical Society of Edinburgh, 1836.
Member of the Lyceum of New York, 1837.
Was appointed Deputy-Lieutenant of Kinross-shire in 1825.

Dr Arnott was also Vice-President of the Royal Caledonian Curling Club, and was lately acting Depute Grand Master of the Royal Order of Masons of Scotland



Castacane degli Antelminelli, Conte Abate Francesco (1886) Botany - Vol. 2: Report on the Diatomaceae collected by H. M. S. Challenger during the years 1873-1876, Report on the Scientific Results of the Voyage of H.M.S. Challenger During the Years 1873-1876 Under the Command of Captain George S. Nares and the Late Captain Frank Tourie Thomson, R. N., edited by C. Wyville Thompson and John Murray, Her Majesty’s Stationery Office, London, page 1

Chambers, Robert, and Thomas Thomson (1870) Walker-Arnott, George A., LL.D., A Biographical Dictionary of Eminent Scotsmen, Vol. 3, Blackie and Son, Glasgow, Edinburgh and London, pages 605-606

Cleghorn Hugh (1868) Biographical Notice of the late Dr. Walker-Arnott, Regius Professor of Botany in the University of Glasgow, Transactions of the Botanical Society, Vol. 9, pages 414-426

Collectors at Royal Botanical Garden Edinburgh, on line at

Cottam, Arthur (1877) On A New Aulacodiscus, From The West Coast Of Africa, Journal of the Quekett Microscopical Club, Vol. 4, pages 149-153

Deby, Julien (1891) Bibliotheca Diatomologica seu Catalogus Librorum et Collectionum Exsiccatarum Bacillarieas Quascumque Sistentium, Typis Seminarii, pages cxxvi and cxxviii

Desmond, Ray (1994) Dictionary of British and Irish Botanists and Horticulturists, CRC Press, pages 22-23

Donkin, Arthur S. (1869) Notes on certain fresh-water species of Diatomaceae, Quarterly journal of Microscopical Science, Vol. 9, pages 397-400

Edwards, A. Mead (1876) On Phipson on diatoms, American Journal of Microscopy and Popular Science, Vol. 1, pages 129-230

The History of the Collections Contained in the Natural History Departments of the British Museum, Volume 1 (1904) Trustees of the British Museum, London

National Botanic Garden of Belgium, on line at

Journal of Botany (1907) Booknotes, news, &c. (on the disposition of Rylands’ diatom collection), Vol. 45, pages 455-456

Journal of the Quekett Microscopical Club (1871) Donations to the Club, Vol. 2, page 247

Lang, Frederick H. (1870) On selecting and mounting diatoms, reprinted in English Mechanic and World of Science, vol. 12, pages 270-271

Nuttall, Robert (2009) Notes upon an excursion to the Pyrenees: William Smith’s last collection of diatom slides, Quekett Journal of Microscopy, Vol. 41, pages 45-52