This post is part of BHL at 20: Treasures from the Biodiversity Heritage Library, a series contributed by members of the BHL community, highlighting remarkable works from across the collection in celebration of its 20th anniversary.

As the Cataloging and Digital Resources Librarian for the Academy of Natural Sciences (Academy) of Drexel University, I get to work with a lot of different materials including periodicals, rare books, archival manuscripts, and more. I recently had the joy of working with scientists’ handwritten notebooks and field journals while completing a project to have 83 of them digitized and transcribed for BHL.

One of the selected notebooks stood out to me: A notebook containing an entomological essay by Carrie Aaron, in part because it highlights a common problem encountered when researching women in the natural sciences. Before uploading the notebook to BHL, the original finding aid record described Carrie as “Mrs. Aaron” and did not provide any additional information about her. Thankfully, Academy Archivist Jessica Lydon noticed the issue and provided more details for me to add to the record, leading me to build a BHL Creator ID for Carrie Aaron that links to her Wikidata identifier. This might sound like a small detail only librarians would notice, but it’s a huge step in building recognition for an author.

Page 1 of A notebook containing an entomological essay by Carrie Aaron, 1889, 1890, 1901, Small Collections and Individual Manuscripts Box 4, ANSP-Coll-0156, Carrie Baily Aaron Papers, Library and Archives, Academy of Natural Sciences of Drexel University, Philadelphia, Pennsylvania.

The updated catalog record provides more context around Aaron’s essay, which she submitted to a contest aimed at gathering information on how to eradicate mosquitoes. In Aaron’s written biographical notice about contest-holder Robert Henry Lamborn, she said, “While engaged in building the Lake Superior Railroad, Dr. Lamborn suffered so from the attacks of countless mosquitos, that he became interested in extermination of the insect, and later offered prizes for the three best essays on the subject.” I wonder if this was the motivation behind her essay submission.

With the help of dedicated Drexel University student digitization assistants, the Academy Library and Archives was happy to contribute the beautifully handwritten notebook to BHL, which showcases Aaron’s extensive entomological knowledge. Included are analyses of potential methods to reduce mosquito populations, including the use of dragonflies, which Aaron called “the hawks of the minuter insect world.”

A page from Carrie Aaron’s notebook on BHL in which she refers to hammer-headed dragonflies as “the hawks of the minuter insect world”. (A notebook containing an entomological essay by Carrie Aaron, 1889, 1890, 1901, Small Collections and Individual Manuscripts Box 4, ANSP-Coll-0156, Carrie Baily Aaron Papers, Library and Archives, Academy of Natural Sciences of Drexel University, Philadelphia, Pennsylvania.)

Aaron and her researchers apparently even attempted to inoculate themselves with what was then described as poisonous droplets from mosquitoes, but the attempt was “not successful, owing probably to the inferiority of the needle as an injector, compared with the delicate hypopharynx.” The essay was later published with other submissions in Dragon Flies vs. Mosquitoes: Can the Mosquito Pest be Mitigated? under the title “The Dipterous Enemies of Man.”

In addition to the essay, Aaron’s notebook in the Academy’s collection contains a letter from Henry Skinner congratulating Aaron on her prize-winning essay and confirming that her entomological reputation would “now be well established.” Ten years after receiving the congratulatory letter, Aaron wrote to Skinner in 1900 asking that her name be removed from the list of associate members of the American Entomological Society: “During the ten years of my membership I have attended only two meetings; this has not been from lack of interest as much as from the fact that lady members are too greatly in the minority, and also that I care so little for the classification of insects.” This is not to say that Aaron was not grateful to Skinner for their “more than thirty year sympathetic friendship,” for which she thanked him in a letter she wrote in 1923.

Carrie Aaron asking that her name be removed from the list of associate members of the American Entomological Society. (Carrie Aaron letter to Henry Skinner, January 11, 1900, Box 1, Folder 1, ANSP-Coll-0150, American Entomological Society correspondence, Library and Archives, Academy of Natural Sciences of Drexel University, Philadelphia, Pennsylvania.)

When given the opportunity to write a blog post in celebration of BHL’s 20th anniversary, it was an easy choice among the Academy Library and Archives staff to write about Carrie Aaron. The timing couldn’t have been better; shortly after choosing our blog post topic, we welcomed intern Will Le, who is currently digitizing our entire American Entomological Society (AES) correspondence collection, including letters written by Aaron, and uploading it to PA Photos and Documents. Funding for this project was generously provided by Dr. William Day and the American Entomological Society. Shout-out to Will Le, Jessica Lydon, Greg Cowper, and the American Entomological Society for making this happen!

Thanks to our intern and the AES digitization project, I was able to read Carrie Aaron’s letters on my laptop and learn about her travels in Santa Monica, a place she describes as “the land of perpetual bloom and uninterrupted sounds of birds and insects.” Later in this letter, Aaron describes a meaningful experience while visiting museums:

At Avalon we met the only woman curator of marine objects in the world and because she noticed how interested I was, also inquisitive, she shared a willingness to dissect and classify me; her museum contained many natural curiosities found in the waters of that locality. The most interesting museum I have ever seen is in Los Angeles, Exposition Park (of 130 acres) owned by the state, the resources and industries of California are shown in most attractive scenic effects. The exhibit of fossil remains of prehistoric animals really is wonderful, and made me regret not being healthy enough to make our Academy of Nat. Sci. a competitor in ownership of such a valuable contribution to scientific knowledge.

Aaron describes meeting “the only woman curator of marine objects in the world.” (Carrie Aaron letter to Henry Skinner, March 8, 1926, Box 1, Folder 1, ANSP-Coll-0150, American Entomological Society correspondence, Library and Archives, Academy of Natural Sciences of Drexel University, Philadelphia, Pennsylvania.)

Now I have a new research topic: who was the “only woman curator of marine objects in the world” Aaron was so excited to meet? To be continued!

After working with archival notebooks and reading Carrie Aaron’s letters, I’m thrilled to see how digitization and public access to collections spur research into lesser-known individuals and uncover more potential research subjects! I don’t consider myself a historian, but it’s difficult to resist historical research when presented with easily accessible primary sources and when given the tools to link subjects across different platforms. I hope to continue this energizing work at the Academy of Natural Sciences in collaboration with BHL for years to come.

From the Biodiversity Heritage Library

For 20 years, BHL has helped uncover the people and stories hidden within biodiversity literature and archives, making them freely available for new generations to discover. Your support helps us continue digitizing, connecting, and sharing collections like Carrie Aaron’s notebook—and ensures that more overlooked voices and histories can be found.

This post is part of BHL at 20: Treasures from the Biodiversity Heritage Library, a series contributed by members of the BHL community, highlighting remarkable works from across the collection in celebration of its 20th anniversary.

We are now exactly halfway through our 20th Anniversary blog post series. Coordinating this celebration of treasures chosen by our BHL community has been one of the most rewarding projects in my time as BHL’s Communications Director. It is an absolute honor to share mine now.

My favorite treasures in BHL are the very first scientific descriptions of new species. I like to think of these descriptions as a species’ international debut in the literature.

The now-extinct Eastern Hare-wallaby, (Lagorchestes leporides), illustrated by Henry Constantine Richter in John Gould’s A Monograph of the Macropodidae, or Family of Kangaroos (1841), Plate 12. Gould formally described the species earlier that year in the Proceedings of the Zoological Society of London.

As the Manager of BHL Australia, the descriptions I love the most are those of Australian species. Australia was one of the last continents to be encountered and documented by European naturalists. British colonization did not begin until 1788, but from the late eighteenth century onward, descriptions of Australia’s bizarre marsupials and monotremes began appearing in European literature thick and fast, accompanied by a buzz of excitement and wonder.

I find it fascinating to read the awe and curiosity of those early naturalists as they tried to fit Australia’s truly perplexing creatures into their existing understanding of the natural world. One of my absolute favorites is George Shaw’s 1799 description of the platypus: “Of all the Mammalia yet known,” he wrote, “it seems the most extraordinary…” I encourage you to read the full description. It’s wonderful.

But today – on Australia’s National Threatened Species Day – I want to talk about the most precious of these treasures: the descriptions of species that disappeared from the living world a devastatingly short time after making their debut in the scientific literature.

European colonization had devastating consequences for Australia’s native biodiversity. Australia’s long isolation as an island continent meant that many of its endemic animals were exceptionally vulnerable to the onslaught of introduced placental predators and competitors. The introduction of foxes and cats in particular, combined with the unprecedented destruction of the natural environment, has resulted in Australia having the highest rate of mammal extinctions in the world.

Tragically, many of Australia’s introduced species were deliberately released in attempts to make Australia more like Europe, a history I explored in an earlier BHL blog post, Exploring the Acclimatisation Society of Victoria’s Role in Australia’s Ecological History).

BHL: a treasure trove of lost species

While museum specimens may continue to reveal information about the anatomy, genetics and diet of extinct species, the literature preserves precious details from observations of living animals: their behavior, abundance, habitats, interactions, and how they were understood and perceived over time.

Scattered throughout BHL are descriptions, field observations, and illustrations of Australian species that have since disappeared: the Pig-footed Bandicoot, Lesser Bilby and Crescent Nail-tail Wallaby, and so many more. These depictions of once-living animals are now invaluable records of species that will never be observed again.

Henry Constantine Richter’s beautiful illustration of the now-extinct Pig-footed Bandicoot, from John Gould’s The Mammals of Australia 1863. Contributed by Smithsonian Libraries and Archives. View in BHL

It is our hope that by making this historic literature accessible and discoverable, we may learn from the past, and help prevent more species from becoming records of what has been lost.

The Thylacine: “an animal of the past”

Australia’s most well-known extinct species is the thylacine, or Tasmanian tiger. This dog-like marsupial carnivore was relentlessly persecuted as a threat to livestock, with private and government bounties placing a price on its head. Hunting and trapping, along with habitat destruction and fragmentation, drove it into rapid decline. The last known thylacine died in captivity at Beaumaris Zoo in Hobart on September 7, 1936. The species had been granted legal protection only two months earlier.

Australia’s National Threatened Species Day marks the anniversary of that tragic death: 90 years ago today.

BHL preserves a sobering scientific trail of the thylacine, documenting the brief period within which this beautiful species was observed, named, misunderstood, persecuted and, ultimately, lost. The first published scientific description and illustration of the thylacine appeared in the Transactions of the Linnean Society of London in 1808. Its author, George Prideaux Robert Harris, gave it the name Didelphis cynocephala (the “dog-headed opossum”). Harris wrote that its large black eyes gave it “a savage and malicious appearance” and compared it to the wolf or hyena.

The first published illustration of the Thylacine, accompanying George Prideaux Robert Harris’s 1808 description in “Description of Two New Species of Didelphis from Van Diemen’s Land,” Transactions of the Linnean Society of London 9: 174–178. Contributed by Missouri Botanical Garden, Peter H. Raven Library. View in BHL

These negative words would echo through subsequent accounts. In 1838, Tasmanian naturalist Ronald Campbell Gunn reported that thylacines attacked sheep at night and were “so very large and powerful, that a number of dogs will not face one”. More than three decades later, Johan Ludwig Gerhard Krefft described the thylacine as “a dangerous creature” and “the largest and most ferocious of the whole Mammalian Fauna in Australia”. Modern research, however, suggests that the thylacine was probably poorly equipped to take down an adult sheep, making its reputation as a formidable livestock killer all the more tragic.

Yet, among these hostile accounts are warnings of the thylacine’s diminishing numbers. Joseph Wolf, one of the nineteenth century’s most celebrated zoological artists, depicted thylacines for the Proceedings of the Zoological Society of London (1850) and later for his magnificent Zoological Sketches (1861). His drawings were based on observations of a living pair of juvenile thylacines at London Zoo, the first thylacines ever to be exhibited in a zoological garden. In the accompanying text, zoologist Philip Lutley Sclater warned:

“The thylacine originally preyed on the Kangaroos and Bandicoots, but since the introduction of sheep into the colony, it has become more addicted to attack sheep folds. Perpetual war is therefore waged against it by the Tasmanian shepherds, whose determined persecution must eventually lead to its extinction.”

Joseph Wolf’s illustration of the two living thylacines on display at London Zoo, from the Proceedings of the Zoological Society of London (1850). Contributed by Harvard University, Museum of Comparative Zoology, Ernst Mayr Library. View in BHL

And then, in 1863, alongside one of the most famous illustrations of the thylacine, by Henry Constantine Richter for John Gould’s The Mammals of Australia, Gould gave an even more chilling prediction:

“When the comparatively small island of Tasmania becomes more densely populated, and its primitive forests are intersected with roads from the eastern to the western coast, the numbers of this singular animal will speedily diminish, extermination will have its full sway, and it will then, like the Wolf in England and Scotland, be recorded as an animal of the past: although this will be a source of much regret, neither the shepherd nor the farmer can be blamed for wishing to rid the island of so troublesome a creature. A price is already put upon the head of the native Tiger, as it is called; but the fastnesses of the Tasmanian rocky gullies, clothed with impenetrable forests, will, for the present, preserve it from destruction.”

John Gould was right: Tasmania’s gullies and forests protected the thylacine for the present – for his present. Seventy-three years later, the last known thylacine was dead.

The thylacine, illustrated by Henry Constantine Richter, from John Gould’s “The mammals of Australia” (1863). Contributed by Smithsonian Libraries and Archives. View in BHL

Treasures lost, then found

Thankfully, not every story ends with extinction. One species in BHL is particularly close to my heart: the Leadbeater’s possum.

Also known as the fairy possum, the Leadbeater’s possum entered the scientific literature in 1867, when Frederick McCoy described it as both a new species and a new genus. McCoy was the first Director of the National Museum of Victoria, the institution now known as Museums Victoria, where I have worked for the past 23 years.

McCoy was renowned for spending substantial sums on books, an extravagance I will forever be grateful for. He ordered the latest scientific publications from Europe to be shipped to Australia at great expense, building what would become one of Australia’s largest and most significant natural history library collections. More than 150 years later, many of these nineteenth-century treasures are freely accessible on BHL, thanks to my wonderful team at BHL Australia.

McCoy named the new species Gymnobelideus leadbeateri, after John Leadbeater, the Museum’s first taxidermist. His original description includes a black-and-white illustration drawn from this specimen by Arthur Bartholomew. The image was later reworked by artist and lithographer Dr. John J. Wild, into the beautiful full-color plate that was published in McCoy’s Prodromus of the Zoology of Victoria (1885).

Left: Arthur Bartholomew’s original illustration of the Leadbeater’s possum, accompanying McCoy’s first published description, On a new genus of Phalanger (1867). Right: Plate 91 by Dr. John J. Wild for McCoy’s Prodromus of the Zoology of Victoria (1885).

Only a handful of Leadbeater’s possums were recorded over the next few decades, and when no sightings were made across a period of 50 years, the species was presumed extinct. Then, in 1961, a small colony was rediscovered near Marysville. In 1971, the Leadbeater’s possum was chosen as the faunal emblem of my home state of Victoria. Sadly, despite decades of conservation efforts, the future of our treasured fairy possum is far from secure. The species remains Critically Endangered, threatened by habitat loss and fragmentation, bushfires, climate change, and predation by feral cats.

Protecting our remaining treasures

When I first envisioned this 20th Anniversary series, I imagined it as a celebration of the rare books, exquisite artworks, and unique archives in BHL. Yet, the treasures I find most precious are the species themselves.

BHL provides a window into the point in history when each species entered the scientific record. It also preserves observations of animals that have since vanished: where they lived, how they behaved, how people perceived them, and, occasionally, the warnings that they were disappearing.

The thylacine reminds us what happens when those warnings are ignored. The Leadbeater’s possum is an urgent reminder that sometimes we have a second chance.

For 20 years, BHL has helped preserve the record of life on Earth and make it freely accessible to everyone. My greatest hope for the next 20 is that we use the knowledge preserved across our 64+ million pages not only to understand what we have lost, but to help protect what we still have.

From the Biodiversity Heritage Library

By supporting BHL, you help preserve the knowledge of species past and present and keep it freely available to researchers, conservationists, and policymakers around the world.

This post is part of BHL at 20: Treasures from the Biodiversity Heritage Library, a series contributed by members of the BHL community, highlighting remarkable works from across the collection in celebration of its 20th anniversary.

The Field Museum’s Marie Louise Rosenthal Library is fortunate to have a small fund dedicated to the purchase of rare books. As a result, Library staff are often on the lookout for titles that fall within our natural history collecting scope while also meeting the criteria of being both historically valuable and scientifically significant.

In March, I came across an interesting zoological title for sale: Geographische Geschichte des Menschen, und der allgemein verbreiteten vierfüßigen Thiere, nebst einer hieher gehörigen Zoologischen Weltcharte, a three-volume work on biogeography published between 1778 and 1783 by Eberhard August Wilhelm von Zimmermann, a German geographer, zoologist, and mathematician. The work also includes a fold-out map, Tabula Mundi Geographico Zoologica sistens Quadrupedes hucusque notos sedibus suis adscriptos edidit, which has been described as the first world map of zoological geography, illustrating late-eighteenth-century understandings of the global distribution of mammals.

Before purchasing a title for the rare book collection, I evaluate whether it fits the Library’s collecting scope, whether it is scientifically valuable, which institutions hold copies, and whether a digital version is already available in BHL. As I looked into Geographische Geschichte des Menschen und der allgemein verbreiteten vierfüßigen Thiere, I learned that Zimmermann had published an earlier edition in Latin in 1777 under a different title: Specimen zoologiae geographicae, quadrupedum domicilia et migrationes sistens, which is available in BHL.

A subsequent search led me to another BHL resource: Opinions and Declarations Rendered by the International Commission on Zoological Nomenclature (1954). In Opinion 257, the Commission rejected Specimen zoologiae geographicae, quadrupedum domicilia et migrationes sistens for “nomenclatorial purposes.” In short, the 1777 edition did not satisfy the requirements of Article 25 of the Règles internationales de la nomenclature zoologique, the predecessor of today’s International Code of Zoological Nomenclature. The work was consequently placed on the “Official Index of Rejected and Invalid Works in Zoological Nomenclature.”

The International Commission on Zoological Nomenclature’s 1954 opinion rejecting E.A.W. Zimmermann’s Specimen zoologiae geographicae, quadrupedum domicilia et migrationes sistens (1777) and accepting his later work Geographische Geschichte des Menschen, und der allgemein verbreiteten vierfüßigen Thiere, nebst einer hieher gehörigen Zoologischen Weltcharte (1778–1783).

Even more interestingly, further reading revealed that this opinion had a connection to the Field Museum. The Commission’s ruling stemmed in part from correspondence between Francis Hemming, Secretary of the Commission, and Wilfred H. Osgood of the Field Museum, who advocated for the recognition of Geographische Geschichte. Hemming also consulted Philip Hershkovitz, then Curator of Mammals at the Field Museum, who supported Osgood’s position. (This correspondence is summarized in the published statement of the case.)

Fortunately, the Commission confirmed that binomial nomenclature was applied in Zimmermann’s later publication, and therefore declared Geographische Geschichte des Menschen, und der allgemein verbreiteten vierfüßigen Thiere, nebst einer hieher gehörigen Zoologischen Weltcharte to be included on the “Official List of Works Approved as Available for Zoological Nomenclature.”

It is clear that Zimmermann greatly revised and improved his work in the German edition. Notably, Geographische Geschichte debuted several binomial names that are still attributed to Zimmermann, including Cervus muntjak, Lutra minima (known today as Chironectes minimus), and Canis zerda (known today as Vulpes zerda).

In his 1777 edition, Zimmermann failed to consistently apply binomial nomenclature, instead using a combination of generic or descriptive names. For example, in Specimen zoologiae geographicae, Zimmermann refers to a species of dormouse as Glis seu Rattus somnolentus (Left). However, in volume 2 (1780) of Geographische Geschichte, Zimmermann uses the binomial Myoxus glis (right). Today, the species is known as Glis glis.

In addition to the improved nomenclature, Geographische Geschichte also features an updated version of the Tabula mundi geographico zoologica, which incorporates new geographical information derived largely from recent travelers’ reports, including those from Captain James Cook and his crew. For example, the 1783 map reflects Cook’s “discovery” of the Sandwich Islands (Hawaii) and provides a more complete rendering of the western coast of North America. The Seychelles is also named east of mainland Africa, where the French established their colonial settlement just thirteen years prior.

On the fold-out map, names of quadrupeds are plotted directly onto their geographic ranges. Zimmermann’s use of nomenclature varies here. In some instances, he uses the genus alone; in others, the species epithet or full binomen; and, occasionally, a common name. Castor (beaver), for example, appears across northern North America, as does Bison; Tigris (tiger) can be found in Asia; and Kanguro (kangaroo) appears in New Holland (Australia), where the animal was first recorded for European science by Daniel Solander, a botanist aboard Cook’s ship, the HMS Endeavour.

Tabula mundi geographico zoologica sistens quadrupedes(1783) from Zimmermann, Eberhard August Wilhelm von. 1778. Geographische Geschichte des Menschen, und der allgemein verbreiteten vierfüssigen Thiere : nebst einer hieher gehörigen zoologischen Weltcharte. Leipzig: In der Weygandschen Buchhandlung. https://www.biodiversitylibrary.org/bibliography/221536.

Finding the work to be historically important to mammalian biogeography, not widely held nor digitized in BHL, and connected to the Field Museum through its role in securing the work’s recognition for zoological nomenclature, I considered this acquisition an obvious choice.

I’m happy to report that Geographische Geschichte des Menschen, und der allgemein verbreiteten vierfüßigen Thiere, nebst einer hieher gehörigen Zoologischen Weltcharte is now available in BHL. Having access to both this three-volume edition and the rejected 1777 title, alongside the International Commission on Zoological Nomenclature’s ruling, provides a compelling case study in the development of zoological nomenclature, the changing standards by which scientific works are evaluated, and the ways in which new evidence can reshape our understanding of the natural world. As the 1954 ICZN opinion suggests, a work published in the 18th century can continue to have a life in the scientific record and be actively reassessed centuries later.

Further reading

In addition to the sources linked above, I also referred to the following:

Allen, J. A. (1902). Zimmermann’s ‘Zoologiae Geographicae’ and ‘Geographische Geschichte’ considered in relation to their zoological nomenclature. Bulletin of the American Museum of Natural History, 16, 13–22. https://digitallibrary.amnh.org/items/22a3b549-b2a3-4e28-b2aa-7758c85641fe

American Society of Mammalogists. (n.d.). Glis glis (Linnaeus, 1766): European fat dormouse. Mammal Diversity Database. https://www.mammaldiversity.org/taxon/1001506

Delaney, J. (2012). First X, then Y, now Z: Landmark thematic maps. Princeton University Library. https://static-prod.lib.princeton.edu/visual_materials/maps/websites/thematic-maps/contents.html

Lotzof, K. (n.d.). Endeavour 250: Natural history through colonial encounter. Natural History Museum. https://www.nhm.ac.uk/discover/hms-endeavour-250.html

From the Biodiversity Heritage Library

For 20 years, BHL has helped bring works like Zimmermann’s out of rare book collections and into the hands of researchers and readers around the world. With your support, we can continue to preserve, connect, and provide open access to the scientific record – including works whose significance is still being rediscovered centuries later.

This post is part of BHL at 20: Treasures from the Biodiversity Heritage Library, a series contributed by members of the BHL community, highlighting remarkable works from across the collection in celebration of its 20th anniversary.

Introduction

Stephen A. Forbes and Charles Robertson were pioneering scientists whose groundbreaking research continues to influence our understanding of the natural world. Forbes advanced the fields of biology and ecology, while Robertson explored bees and their relationships with flowers and other insects. Their careful observations and influential publications laid important foundations for modern biological and entomological research. Their enduring insights remain valuable to researchers, students, educators, and nature fans alike, connecting historical discoveries with contemporary scientific knowledge of biodiversity and ecological interactions. The University of Illinois Urbana-Champaign Library’s contributions of rare archival materials and publications by Forbes and Robertson are valuable additions to the Biodiversity Heritage Library (BHL), improving access to these records for scientists and historians alike.

Stephen A. Forbes

Stephen Alfred Forbes was born on 29 May 1844. He was a professor of zoology and entomology and a leader in the natural sciences at the University of Illinois Urbana-Champaign. His studies included insects, crustaceans, fishes, and birds – and their relationships to the environment. In 1886, he received the first-class medal of the Société d’Acclimation de France for scientific publications. He was appointed director of the Natural History Survey Division in 1917 and led the organization until his death on 13 March 1930 in Urbana, Illinois.

Portrait of Stephen A Forbes from the foreword to “Forbes Biological Station: the past and the promise,” in Illinois Natural History Survey special publication 10 (1989).

Among Forbes’ most influential works is The Fishes of Illinois, which documents over 150 fish species represented by more than 200,000 specimens collected from 102 Illinois counties. These fish are depicted in richly detailed color paintings by illustrators Lydia M. (Hart) Green and Charlotte M. Pinkerton. You can read more about the lives and work of these women in our previous blog post, written by Susan Braxton. The publication also includes detailed distribution maps, making it a valuable reference for aquatic biodiversity and fisheries research.

Illustration of Chrosomus featured in The Fishes of Illinois (1908).

In 1894, he established the Forbes Biological Station and, in 1896, directed the construction of a 48-foot floating biological laboratory at the site on the Illinois River in Havana, Illinois. The Station was specifically created to support continuous scientific investigation. It is no wonder that the Illinois Natural History Survey (INHS) celebrated the 150th anniversary of Forbes’ birth on 26 May 1994.

Image of a cabin boat from “Forbes Biological Station: the past and the promise”, in Illinois Natural History Survey Special Publication 10, p. 17 (1989).

Today, Forbes Station is used to advance science and policy in the Illinois River Valley and beyond. It houses the Frank C. Bellrose Waterfowl Research Center, whose research focuses on wetlands, waterfowl, and marsh birds. Today, the Illinois Natural History Survey operates six other field stations: Great Rivers Field Station, Illinois River Biological Station, Kaskaskia Biological Station, Lake Michigan Biological Station, Ridge Lake Biological Station, and Sam Parr Biological Station – all serving researchers from the University of Illinois Urbana-Champaign and across the state. BHL has an extensive collection of these and related publications, chronicling Forbes’ contributions to the understanding of ecology and the foundation of aquatic ecosystem science.

Forbes’ Memorial captures the impact he had on his contemporaries, the University of Illinois, and the state. The University Senate put forth a resolution acknowledging Forbes’ significant contributions:

The Senate knew him as Professor of Zoology and Entomology and Dean of the College of Science; it admired his sagacity and patience as chairman of its Committee on Educational Policy; its members loved him for his simplicity, sincerity and broad human interests. The University and the State are immeasurably indebted to him as one of their most useful and eminent laborers for the common good.

Charles Robertson

Charles Robertson was born on 12 June 1858 in Carlinville, Illinois. He began his academic education at Blackburn College in his hometown and continued his studies in botany and zoology at Harvard University. He returned to Blackburn College as a professor of biology and Greek. His research centered on investigating interactions of insects and flowering plants. Over more than 20 years, Robertson recorded visits by 1,429 pollinating insects (including flies, beetles, butterflies, and bees) to 456 plant species. He was collecting insects in Florida just a few months before his death on 1 June 1935 in Carlinville. His book, Flowers and Insects, published in 1928, presents an intensive study of flower-visiting insects from the city of Carlinville and remains one of the most comprehensive studies conducted in a single locality. Each insect he recorded was associated with the plant on which it was collected.

Portrait of Charles Robertson from History of Macoupin County, Illinois: Biographical and Pictorial, vol. 2 (1911), edited by Charles A. Walker. Image enhanced using Adobe Photoshop by T. C. McElrath. Source: Wikipedia

His personal life mirrored his work: he was born and died in the same small town, kept few but lasting friendships, and brought the same steady, unhurried patience to his acquaintances that he brought to a lifetime of observing flowers and their visitors.

Charles Robertson’s specimen collection logs document insect specimens and include information such as the specimen number, scientific name, sex, date and locality of collection, insect order, and scientific name of the host plant. His collections and correspondence have proved invaluable to researchers. His work was essential to an investigation of species decline in Carlinville, published in Ecology & Society and conducted by John Marlin, a research affiliate with the Illinois Sustainable Technology Center and INHS. A quantitative analysis published in July 2026 in the Data Science Journal highlights the wealth of knowledge contained in his correspondence and collection logs. The logs and most of Robertson’s papers from 1877 to 1935, including correspondence, reprints, five ledgers, and a data book on bee research, are preserved in the University Archives at the University of Illinois Urbana-Champaign. The seminal work Flowers and Insects, as well as his specimen collection logs, is readily available through BHL.

Side-by-side images of page 5 of the handwritten Specimen Collection Logs of Charles Robertson, vol. 1, 1884-1886. Images assembled by Kelli Trei.

Conclusion

These collections preserve the irreplaceable life’s work of two Illinois scientists. Forbes’ work remains important today. His holistic view of ecology, examining the relationships between organisms, the environment, and natural-resource industries, has helped shape our current understanding of applied ecology. Robertson’s correspondence and specimen logs represent an irreplaceable record of an ecosystem that can no longer be observed firsthand.

Archival documents such as these reveal the values, culture, and identity that shaped the Illinois Natural History Survey and science in Illinois. Being able to trace the legacy of scientific research and lives of those behind these discoveries provides richer context and understanding for future scientific research. BHL provides a unique juxtaposition between the human experience of doing science, revealed through archival documents, and the official scientific record preserved in books and journal articles. Together, these materials provide a fuller and more inclusive account of the history of science here in Illinois.

From the Biodiversity Heritage Library

For 20 years, BHL has helped preserve and share the scientific record, from landmark publications to the archival materials that illuminate the people, places, and observations behind them. With your support, we can keep treasures like these freely accessible, connecting past research with the scientists, historians, and communities who continue to learn from it today.

This post is part of BHL at 20: Treasures from the Biodiversity Heritage Library, a series contributed by members of the BHL community, highlighting remarkable works from across the collection in celebration of its 20th anniversary.

In 1849, the first volume of the Papers and Proceedings of the Royal Society of Van Diemen’s Land launched a tradition of advancing knowledge that continues to this day. Established in 1843, the Society is Australia’s oldest Royal Society, and for more than 180 years its prestigious journal of scientific and cultural history has captured the changing face of Tasmania, initially called Van Diemen’s Land by British colonists.

Cover of the first volume of the Papers and Proceedings of the Royal Society of Van Diemen’s Land, 1849.

Window to colonial Tasmania

Volume One, published in three parts from 1849 to 1851, is a weighty mix of scientific papers, meeting reports and miscellaneous records. It sets the scene with a detailed analysis of the colony’s diverse population and weather, extending to nearly fifty pages of charts, tables and data. Papers on new building techniques, coal exploration, agriculture and manufacturing provide a fascinating snapshot of colonial enterprise as settlers sought to understand this new land and what it had to offer. In the natural sciences, contributions from a veritable ‘Who’s Who’, including John Edward Gray, John Gould and Frederick M’Coy, helped unravel the mysteries of ancient fossils and remarkable living creatures such as the platypus.

Plate XI from Frederick McCoy’s paper on fossil zoology and botany, V.1, Papers and Proceedings of the Royal Society of Van Diemen’s Land, 1849.

These early volumes document many of the human-driven changes that typically occur when new lands are seized and colonized. They also contain an invaluable timeline of just how quickly Tasmania’s Indigenous-managed landscape would change and it is the seemingly incidental reports presented at Society meetings that offer the richest insights.

In 1849, Mr Hull described a gigantic blue gum about six miles from Hobart Town, measuring 28 yards (25.6 metres) in circumference and estimated to be 330 feet (100.5 metres) high. Mr Champ donated a small spotted fish preserved in spirits that appeared to possess four legs with finger-like appendages, and Mr Milligan reported that two live thylacines sent to London the previous year had now arrived safely.

Specimens of the fungus known as ‘native bread‘ (Mylitta sp.), eaten by Tasmanian Aboriginal people, were presented for examination, with notes that, when grated and made into a pudding with milk, they were ‘very palatable’. A sample of white resin from the Oyster Bay pine was described as coming from a tree with an extremely restricted distribution, yet one highly suitable for local building and carpentry purposes. Today, the South Esk Pine Nature Reserve protects one of the few remaining stands of this endangered species.

Another insightful paper is by renowned naturalist Ronald Campbell Gunn, who explains how the ‘flying squirrel’ (the sugar glider) became naturalised in Tasmania after first being imported as a pet during the 1830s, quickly escaping and then establishing in the wild. Few at the time could have imagined that this pocket-sized pet would one day threaten Tasmania’s endangered swift parrot by preying on nesting females, eggs and chicks.

Perhaps read with the keenest interest was Captain Charles Stanley’s paper on the practicalities of introducing trout into Tasmania’s waterways. When live fish ova were eventually transported to the Salmon Ponds at New Norfolk and later released, Tasmania’s river systems would forever contain an introduced predator.

Beyond the science

Beyond the scientific papers, early journals also recorded the Society’s own activities: its office-bearers, donations, acquisitions and financial accounts — the administrative details most of us tend to ignore. Yet these records reveal the people who helped shape nineteenth-century Tasmania. The Society’s office-bearers were among the colony’s most influential figures, and meetings regularly attracted generous donations of books, artworks, natural and geological specimens, artefacts and more.

These gifts formed the foundation of collections that are today internationally recognised and housed in the Royal Tasmanian Botanical Gardens, the Tasmanian Museum and Art Gallery, and the Royal Society of Tasmania’s own Art and Library Collections. The journal documents not only the birth of these important institutions but also the determination, debate and politics involved in establishing them.

Within forty years of British settlement, Van Diemen’s Land was no longer merely a colonial outpost at the edge of the world. It had grown into an increasingly connected, resourceful and enterprising community pursuing scientific knowledge, economic opportunity and civic benefit. The Papers and Proceedings chronicle that remarkable transformation.

However, journals produced by colonial administrators inevitably reflect privilege and European perspectives and overlook Indigenous voices and other harsh injustices. It is often what is absent from the record, or now challenges contemporary values, that makes these volumes so compelling yet at times uncomfortable, to read.

Illustrations of Lerp and Psyllids associated with eucalypts, from Dobson’s paper, V.1, Papers and Proceedings of the Royal Society of Van Diemen’s Land, 1849.

Where to now?

Today’s Papers and Proceedings continue to focus on Tasmanian and Antarctic natural science but also encourage broader social and cultural themes. Recent volumes have contributed to truth-telling and historical accountability, including the publication of the Royal Society of Tasmania’s joint Apology to Tasmanian Aboriginal people in 2021 and papers arising from the Society’s annual Tasmanian Aboriginal Lecture.

Through the amazing Biodiversity Heritage Library’s open-access repository, researchers can apply computational tools to journals spanning more than 175 years, unlocking hidden insights that manual reading can miss. The complete digitised collection of thePapers and Proceedings of the Royal Society of Tasmania is freely available through BHL.

In an era increasingly dominated by artificial intelligence and social media, this journal remains as relevant as ever and is one of the Royal Society of Tasmania’s greatest legacies. More than simply words on a page, the Papers and Proceedings is a window into the environments, cultures and politics that continue to shape this unique island.

From the Biodiversity Heritage Library

For 20 years, BHL has made journals such as the Papers and Proceedings of the Royal Society of Tasmania freely accessible to researchers and readers around the world. With your support, we can continue preserving these irreplaceable records for generations to come.

This post is part of BHL at 20: Treasures from the Biodiversity Heritage Library, a series contributed by members of the BHL community, highlighting remarkable works from across the collection in celebration of its 20th anniversary.

One of the greatest challenges for a digital library, especially one as large as the Biodiversity Heritage Library, is simply finding the content you are after. Recently, I made a website to give a sense of this challenge. The website features about 200,000 pages of content from BHL Australia, a small fraction of what is in BHL overall, but already it’s something of a challenge to find specific items you might be after. If you were looking for a particular article, how would you find it?

Interactive browser of BHL Australia

Articles, articles, articles

For most scientists, the article is the fundamental unit of research, not the journal title, and not a journal volume. The article is what we download as a PDF, what we store in our reference managers, and what gets cited. At the outset BHL did not have articles, so over a decade ago I set about developing a tool to find those. This tool became BioStor, which was described in a paper in 2011 (Extracting scientific articles from a large digital archive: BioStor and the Biodiversity Heritage Library). The basic idea behind BioStor is to take information about an article, such as journal, volume, pages, and year, and then try and find that article in BHL.

Mapping journal, volume, and pagination from an article to BHL.

In principle this seems straightforward, but often the vagaries of metadata complicate the task. The image below shows some of the issues encountered with the journal Ibis. The source of metadata for the articles was CrossRef, via a commercial publisher (Wiley). You might expect this data to be high quality, but it contains errors such as bad character encoding. To further complicate things, Wiley decided to renumber all the volumes of the journal, so that the original volume information we see in BHL (such as series 2, volume 1) bears little relation to what is in CrossRef (volume 7, issue 1).

Matching CrossRef metadata for an article in Ibis to BHL.

The list of metadata messes like this is almost endless. There are journals that have more than one numbering system for the same volumes (e.g., Annali del Museo civico di storia naturale Giacomo Doria where the same item is both series 3, volume 7 and volume 47), there are multiple abbreviations for the same journal, and there are journals with multiple names (e.g., title 8097 is “Annuaire du Musée zoologique de l’Académie des sciences de St. Pétersbourg”, “ЕЖЕГОДНИКЬ ЗООЛОГИЧЕСКАГО МУЗЕЯ ИМПЕРАТОРСКОЙ АКАДЕМІЙ НАУКЬ”, and “Ezhegodnik Zoologicheskago muzeia …”).

A further complication is that a scanned item in BHL may contain several issues or volumes, each with its own set of overlapping page numbers, which means we have to decide which page “1” is the page 1 that matches the article we are searching for. Once we solve all that, we encounter further problems. Perhaps the most challenging is pagination. In most modern articles, the page range, e.g. 1–5, completely encompasses the article, including figures, charts, illustrations, etc. But for the older literature this is often not the case. Typesetting text and reproducing plates were different processes, and hence the plates might be disconnected from the article (often appearing at the end of a volume). This means that extracting, say pages 1–5, from BHL is no guarantee that you have the whole article.

A good deal of code in BioStor is trying to make sense of matching article metadata to BHL items, finding the correct page to match to, and extracting the set of pages that correspond to that article, as well as providing tools to manually correct metadata and add missing pages (for example, the plates mentioned above). Hence the process of finding articles is, at best, semiautomated.

BioStor old and new

The original BioStor website dates back to 2009, and looked something like this:

Original BioStor website.

This site could display individual articles, and you could edit metadata. For a variety of reasons, it was no longer feasible to host this at the university where I was based, so I split the website into two versions. The original site now runs only on my laptop, and I use it to process files and locate articles in BHL. The new version runs in the cloud and features a cleaner interface, along with much better search. Below is the same article in the current BioStor.

Current BioStor website.

Once articles are discovered using the old BioStor, they get pushed to the public version of BioStor at https://biostor.org. This website is also the point of contact between BioStor and BHL: each day BHL runs an automated process which asks BioStor whether it has any new articles, and, if the answer is yes, it fetches those and adds them to BHL (in BHL articles are referred to as either “parts” or “segments”). The end result is that articles defined in BioStor now become visible in the Table of Contents in BHL.

BioStor article displayed in BHL.

One advantage of having a separate project such as BioStor is that I can use it to experiment with different ways to view BHL content. For example, BioStor looks for geographic coordinates (latitude and longitude) in the OCR text for each article. Any pairs of coordinates that it finds get stored in a map, which you can browse. In the diagram below we have selected a small region in the centre of the map, on the right you can see a list of articles about that area.

Maps showing localities on the island of Sulawesi that are mentioned in BioStor articles.

Identifiers

BioStor has been running since 2009. In that time it has contributed over 260,000 articles to BHL, making it the single largest source of BHL “parts”. Having articles is nice, but even better is having articles with persistent, citable identifiers, such as DOIs. The Persistent Identifier Working Group has been working to add DOIs to BHL content, especially “parts”. This work has focused on two kinds of DOIs. The first are existing DOIs minted, for example, by commercial publishers. BioStor adds a lot of articles using CrossRef metadata, so we get these “for free” (there are other sources of DOIs that BioStor uses, but that is another story). Why does it matter to have external DOIs for BHL content? Well, many of these articles are free in BHL but behind a paywall on the publisher’s website. Services such as Unpaywall can link existing DOIs to free versions of the corresponding article, and BHL is one of Unpaywall’s providers.

But the more exciting (and onerous) task is minting new DOIs for articles in BHL, so that BHL is the version of record for that content. This has several implications. It means that BHL is effectively a publisher, and has the responsibility to maintain access to this content in perpetuity. It also changes the way we think about adding articles. For example, most of my work with BioStor has been opportunistic – I’m working on a taxonomic database, I see that there are some papers that should be in BHL, find them, then add them to BioStor so future BHL users can find those articles. But once we start creating DOIs, the goal is quite different: you want to get every article in the journal that is in BHL, and mint DOIs for all of them. While this appeals to a completionist mindset, it does mean getting metadata for every article before you can add DOIs.

Luckily, the hard work in minting DOIs has a striking payback, we can see how many times articles in BHL are cited in the scientific literature. The last time the results were analyzed, BHL articles had been cited some 74,446 times! Without BHL these publications would appear as simple text strings in the literature cited, now they are first-class digital citizens with clickable DOI links.

Metadata matters

By now it is obvious that the way BioStor finds articles depends on having good quality metadata for articles (or chapters), which it then attempts to locate in BHL. The lack of freely accessible metadata is a major impediment to increasing the rate at which articles are added. In the past I have made extensive use of taxonomic databases as a source of bibliographic data (see my BioNames project, for example). Yet the quality of citations in these databases is often poor. I have also made extensive use of sources such as CrossRef, which covers articles that have been assigned DOIs by that agency, and also data provided by volunteers, such as those working with Nicole Kearney (thank you Bob Griffith and Heidi Griffith!). Another major source of data has come from scraping the web, a time-consuming process that is becoming increasingly difficult to do as the web becomes increasingly closed under the onslaught of AI bots (see also Joel Richard’s blog post A Brief Bit on BHL Battling a Barrage of Bots).

There is a clear need for a free and open bibliographic database. The nearest we have is OpenAlex, whose tagline is “All the world’s research, connected and open.” Sadly this is still more of an aspirational goal rather than a fact: a lot of taxonomic literature is not in OpenAlex. Perhaps it is time, therefore, to revive “CiteBank”, which was an early BHL project to collect bibliographic metadata. If we had a comprehensive database of the taxonomic and related literature, locating articles in BHL would be a much easier task.

Machines reading

BioStor’s method of finding articles works, but it is not the only way we could locate articles. Instead of relying on external sources of metadata, what if we could simply have a computer read the volume and extract the articles automatically? Early attempts to do this for BHL content were not particularly successful, see for example A metadata generation system for scanned scientific volumes. But the advent of large language models (LLMs) and AI chatbots has dramatically changed the way we can tackle finding articles in BHL. In my own work I routinely use AI to extract articles in bulk from a scanned volume. Typically the approach involves finding tables of contents in the scanned volume, using AI to parse that into structured data, then finding the corresponding pages in the volume, checking that they match the table of contents, and then using AI to extract bibliographic data (e.g., article title, authors, etc.). The result of this process is a data file that gets fed into BioStor, so that articles get found and added to BHL in the usual way. It is not bulletproof, and AI can quite happily make mistakes, but in my experience it works well.

But the holy grail would be to simply point an AI at a volume and it would identify and extract all the articles, find any stray plates, and present the results to BHL. Given the spectacular advances in OCR text and understanding document layout in recent years, perhaps there will be a point where BioStor can gracefully retire from the scene. Its hundreds upon hundreds of lines of regular expressions and special-case hacks quietly gathering dust in a GitHub repo while machines of loving grace read BHL for us.

From the Biodiversity Heritage Library

As BHL celebrates twenty years of open biodiversity knowledge, this post reminds us that access depends not only on digitised pages, but on the tools, metadata, identifiers, and infrastructure that make them discoverable and citable. With your support, BHL can continue strengthening the systems that connect biodiversity literature to the researchers, communities, and future discoveries that depend on it.

This post is part of BHL at 20: Treasures from the Biodiversity Heritage Library, a series contributed by members of the BHL community, highlighting remarkable works from across the collection in celebration of its 20th anniversary.

One afternoon in AD 79 a family had gathered at a villa overlooking the Bay of Naples. Outside, a mother and her seventeen-year-old son observed a strange cloud which had appeared in the distance. The mother, Plinia, saw it first, but it would be her son, Pliny the Younger, who recorded for posterity the sight on the horizon and the terrible events that had long since started but were now nearing their catastrophic conclusion. The teenager rushed inside where his uncle, who was also Admiral of the Roman Fleet in the Bay, Pliny the Elder, was reading. The younger Pliny described a cloud in the shape of a pine tree, its branches supported by a thick trunk. From the perspective of a post-twentieth century world, we might now call it a mushroom cloud. But to Pliny the Elder, ever inquisitive, it was like nothing ever seen before and he hastened to investigate.

Anyone with a passing knowledge of Roman history will know that what that confusingly named family had observed was the eruption of Mount Vesuvius. Very soon, Pompeii and Herculaneum would be lost, covered in a pyroclastic flow. What had started as the attractive prospect of observing a volcanic eruption first hand quickly turned to the realisation that a rescue mission was required. Events for the elder Pliny would end at Stabiae. Already suffering from troubled breathing, he was overcome by fumes, or perhaps suffered a heart attack, and died.

Much of what we know of Pliny the Elder comes to us from two letters written by his nephew to the historian Tacitus. Pliny the Elder’s writings were extensive, spanning the wars in Germania, where he served in the cavalry, and a treatise on throwing a lance from horseback to a Latin grammar. All are now lost. Yet one great monument to his learning survives, the Historia Naturalis, here called the Natural History. Divided into 37 books, and likely published posthumously, the Natural History covers topics from astronomy to horticulture.

Book one’s summarium allowed readers to navigate the Natural History. In the NHM’s copy, annotation identifies where in the main work information can be found. Contributed in BHL from the Natural History Museum, London.

The Natural History is sometimes referred to as the first encyclopaedia, yet some recent scholarship has viewed this classification as overly simplistic. There was no ancient tradition of encyclopaedias to which Pliny himself could identify and whilst the author celebrated his accumulation of 20,000 distinct pieces of information, he also intended his work to stand as a coherent whole. By bringing together as much known information as possible, and not just about natural history, Pliny’s work can be seen as an Imperial project. He is laying claim to knowledge for Rome.

The decorated page at the beginning of Book One immediately identifies the work as a luxury product for an elite clientele. Contributed in BHL from the Natural History Museum, London.

From the time of its publication in manuscript form, Pliny’s Natural History was extraordinarily influential. It circulated widely and prior to its first printing some 200 manuscript copies were known to survive. Thus, when the Venetian Senate granted Johann de Speyer a commercial printing licence in 1469, just a decade and a half after Gutenberg used moveable type to publish his Bible, the Natural History was one of the first titles he printed. The copy in the Library of the Natural History Museum in London is one of those 1469 first editions.

Annotations to the margins, here to Book 33, demonstrate use of the volume. Contributed in BHL from the Natural History Museum, London.

Printing in the fifteenth century was, as now, a commercial endeavour and Johann de Speyer knowingly produced a product that would appeal to a wealthy clientele. His edition featured wide margins and decorated letters which echoed manuscript production and spoke of luxury and prestige. These margins also allowed the reader to make annotations, often as a means of navigating the text. In the NHM’s copy, those signs of use are present and at least two hands can be identified in the marginal annotations.

BHL contains a number of incunabula of Pliny (incunabula is the term used to indicate books printed before 1501). There is the 1469 edition from Venice contributed by the NHM and the 1472 edition, also from Venice, held by Boston Public Library. McGill University Library has contributed the 1473 (Rome), 1481 (Parma) and 1497 (Venice) editions. The NHM also holds the 1472 Venice and 1481 Parma editions as well as later copies such as the first English translation produced by Philemon Holland in 1601. Yet it is the de Speyer’s 1469 edition that is the oldest book in our library.

The flyleaf gives provenance and condition information about the volume. Contributed in BHL from the Natural History Museum, London.

At the recent BHL Annual Meeting in London, delegates were given the opportunity to view the NHM’s 1469 Pliny. It has been suggested that only 100 copies of this edition were produced, and it is a wonderful survival of arguably the first printed book on natural history. As noted on the flyleaf, the volume was ‘collated’ and identified as ‘perfect, which is almost a miracle’. In actual fact, two facsimile folios were added at a later date, though this only makes for a more interesting object.

So much has been written about Pliny the Elder and his Natural History. My text lays no claim to originality. Indeed, even the NHM’s copy is relatively well known, having once been celebrated as the oldest item on BHL. As an earlier blog announced that baton has now been passed to the Circa Instans at the LuEsther T. Mertz Library of the New York Botanical Garden, evidence, were it needed, that BHL continues to thrive, with new material added all the time. It’s an endeavour we can be proud of, and one of which Pliny the Elder would certainly have approved.

From the Biodiversity Heritage Library

For 20 years, BHL has made treasures like this freely accessible to the world. With your support, we can ensure these treasures – and the knowledge they hold – remain open for generations to come.

Further reading

The literature on Pliny the Elder and his Natural History is extensive, but the following were useful when preparing this blog.

Chibnall, M., ‘Pliny’s Natural History and the Middle Ages’ in T.A. Dorey (ed.), Empire and Aftermath, Silver Latin II (London, 1975).

Di Tommaso, L., ‘Pliny the Elder: Historia Naturalis’ in J. Magee (ed.), Rare Treasures from the Library of the Natural History Museum (London, 2017), pp. 6-11.

Doody, A., Pliny’s Encyclopaedia: The reception of the Natural History (Cambridge, 2010).

Dunn, D., In the Shadow of Vesuvius: A life of Pliny (London, 2019).

Gudger, E.W., ‘Pliny’s Historia Naturalis: The most popular natural history ever published’, Isis, vol. 6, no. 3 (1924), pp. 269-81.