Botany Today: Specimen Photographs

In this last of a series of posts (1,2,3) on the future of botany, I want to take up a topic that seems to be receiving more attention lately:  the relationships between specimens and photographs.  Even as stout a defender of herbarium specimens as myself has to admit that there is a considerable difference between them and living plants, between brown and virtually two-dimensional as opposed to colorful and in 3-D.  Photographs have the storage advantages of specimens while providing at least some of the information that specimens lack.  In addition, digital photography has made it cheaper to take photographs and easier to store them. 

Yet despite their usefulness, plant photographs, at least for some species, are not easy to come by.  In a 2021 article in Nature Plants, Pitman et al. reported on a survey of 25 online databases of field photographs and found that they held only about 53% of the 125,000 vascular plant species from the Americas.  The databases they searched included those hosted by botanic gardens, natural history museums, and other entities such as Flora of the World and  Also, three social media and community science platforms were surveyed: iNaturalist, Pl@ntNet and Flickr.  These three accounted for 37.8% of the species, and photos of about a third of these species were not found on any other sites.  Flickr and iNaturalist also had the best geographic coverage. 

Not surprisingly, North American species were more likely to be photographed than those of central and South America.  But there were wide variations in coverage, with 71.9 % of Bolivian species pictured versus 56.8% of those in Brazil.  There were also differences among plant families with 98.1% of the Liliaceae captured, but only 18.7% of the Piperaceae, which have less showy flowers.  Not surprisingly, rare plants were less likely to be photographed as were relatively new species.  In addition, the researchers found that when they rechecked their results after several months that a number of species were represented that hadn’t been there earlier.  So this is definitely a changing landscape, but one that’s troubling to those attempting to document and study biodiversity. 

The Americas are not the only areas that have this problem.  A new Australian study of (Mesaglio et al., 2023) revealed that 17.6% of the Australian flora of 21,077 vascular plant species are not represented by any photographs.  Here 33 online resources were used, again including social media and community science platforms.  Obviously the coverage is much better than for the Americas.  Australia has a well-organized system of state herbaria, was an early adopter of digitization, and is able to draw upon an up-to-date list of its species.  Still there are gaps, again related to the rarity of species or their recent discovery, and there are also geographic disparities.  While Western Australia is the most species-diverse state there are some areas that are very difficult to access, hence less photography has been done.  Other reasons for gaps cited by the authors were for plants that are difficult to identify or that lack “charisma.” 

Both articles stress the importance not only of the number of photographs but their quality.  These need to be high-resolution and capture as many of the plant’s identifying characteristics as possible.  Thus the best photographs are likely to be those taken by individuals who know enough about plant systematics to literally focus on identifying traits.  This is a topic that Carlos Gómez-Bellver (2019) and his colleagues in Barcelona address in an article where they propose standards for photographs to complement herbarium vouchers.  However, the guidelines would also be useful for photographs not physically attached to specimens, but linked to them as part of the extended specimen concept. 

The authors list six cases where photos would considerably increase a specimen’s taxonomic value.  First are large species such as a palm, where photos of the plant as a whole and its habitat would help to put the specimen into context.  Succulent or spiny plants, that are difficult to prepare would also benefit from such photos, with only small pieces of the plant itself attached; the same is true of plants with toxic substances.  Then there are species for which little remains but seeds and withered material, also species that lose important morphological traits when they are pressed and dried.  There might be cases where the specimen is the only one in the vicinity, so the photo would serve as a voucher; the same would be true of plants at sacred sites where collection might be considered disrespectful. 

The authors call for the development of a protocol with standards that photographs must meet to be considered as reference material to be tied to a voucher.  I can’t go into all the elements here, but they include reflecting the entire size of the plant and its habitat.  The photo must also include the standard metadata about date and location, the collector, and precise geolocation.  What they term “fusion vouchers” are those that include both a specimen and photos; these would be stored in herbaria.  Photo vouchers alone could be filed in a variety of ways which are discussed.  At this time, there is no standardization.  But as the other articles I’ve discussed here make clear, it would be important for the photos to be accessible digitally.


Gómez‐Bellver, C., Ibáñez, N., López‐Pujol, J., Nualart, N., & Susanna, A. (2019). How photographs can be a complement of herbarium vouchers: A proposal of standardization. TAXON, 68(6), 1321–1326.

Mesaglio, T., Sauquet, H., Coleman, D., Wenk, E., & Cornwell, W. K. (2023). Photographs as an essential biodiversity resource: Drivers of gaps in the vascular plant photographic record. New Phytologist, 238(4), 1685–1694.

Pitman, N. C. A., Suwa, T., Ulloa Ulloa, C., Miller, J., Solomon, J., Philipp, J., Vriesendorp, C. F., Derby Lewis, A., Perk, S., Bonnet, P., Joly, A., Tobler, M. W., Best, J. H., Janovec, J. P., Nixon, K. C., Thiers, B. M., Tulig, M., Gilbert, E. E., Campostrini Forzza, R., … Hilo de Souza, E. (2021). Identifying gaps in the photographic record of the vascular plant flora of the Americas. Nature Plants, 7(8), 1010–1014.

Botany Today: Herbaria

Global map of biodiversity from GBIF occurrce data, showing continued bias in records from the Northern Hemisphere

While the articles I discussed in the last post on important questions facing plant research hardly mentioned herbaria, they are front and center in Charles Davis’s (2023) article: “The Herbarium of the Future.”  It’s an opinion piece in Trends in Ecology and Evolution, so it perhaps takes a broader view of the uses of herbaria than might be found in a systematics journal.  It is also written with a vitality, a lively pace, as if Davis is trying to fit in as much as possible about the promising future of herbaria—and plants—before a reader’s interest might flag.  But this is unlikely since he does a good job of introducing, one after another, aspects of the world of plant collections and how they can be used now and in the future in researching many questions that appeared in the lists of critical issues in the field (see last post).

Davis employs terms that connote change and growth.  His first heading is “A Revolution in Herbarium Use” where he outlines changes in herbaria and in how they are used.  One is what he terms the development of the global metaherbarium:  the growing collection of herbarium specimen data and images available on the internet, in most cases without paywalls.  The Global Biodiversity Information Facility (GBIF) is the largest of these portals, but there are many others including DiSSCo for European herbaria and iDigBio for those in the United States.  The data in these repositories overlap, and yet there really is no “metaherbarium” which harvests information from all other sources.  And there may never be, or at least it will take a long time to get there.

Davis is presenting what the plant science question group calls “horizon scanning,” peering into the future of what might be (Armstrong et al., 2023).  However, there are enormous technical difficulties in linking even collections that are using similar hardware and software.  The plus side is that as these problems have come to light so has the realization that they must be dealt with on a global level (Manzano & Julier, 2021).  The Alliance for Biodiversity Knowledge and other organizations such as the long-standing Biodiversity Information Standards (TDWG) are important forces in moving these goals forward.  The reason for urgency in effectively mobilizing data for all natural history collections is the crying need to use them for research on biodiversity and its conservation, or as Davis puts it: “Innovating Traditional Applications of Herbaria to Speed Discovery.” 

Writing of innovation and speed are rhetorical devices Davis uses to emphasize how critical the situation is.  There are still new species to be discovered, many of these already sitting in herbarium cabinets.  Could AI help to recognize some of them?  Here again, we are still in the early stages, but there have been significant advances in training machine learning systems to identify specimens.  The same is even more true of improvements in “herbariomics,” that is, extracting and sequencing DNA from herbarium specimens, even in cases where they are hundreds of years old.  Davis writes that:  “The metaherbarium soon will become the central resource for such [phylogenomic] investigations spanning populations, communities, and whole continents (p. 4).”  This is definitely on the far horizon.  If collection databases are often difficult to link together, how much more challenging will it be to extract DNA from far-flung collections?  Still, such forward thinking is essential so that possibilities feed into the groundwork now being laid for this bright future.  It includes training individuals worldwide in the skills needed to bring such work to fruition. 

The final section before the conclusion is entitled:  “Breathing New Life into Herbaria: Expanding Users and Novel Applications.”  This doesn’t require as much stretching to see the horizon because much has already happened here.  Ecologists are becoming more aware of herbaria as sources of information on life cycle traits and how they may change over time (Heberling, 2022).  Fifteen years ago phenological studies of the effect of climate change on flowering times were novel; now they have increased to the point of indicating the complexity and variety of species responses, on both small and large geographical scales.  Insect herbivory, fungal relationships, and pollinator interactions can be investigated, often by using more than one kind of natural history collection. 

Herbaria are also important in conservation work, in comparing past plant distributions with those of the present, and in studying how the genetics of populations may have changed over time.  There are really just too many ways herbaria can be used to list them all here or in Davis’s article (Funk, 2003).  However he does give a rather extensive list of uses, including devoting a full-page spread of photos from an exhibit at his home institution, Harvard University.  The Harvard Museum of Natural History opened “In Search of Thoreau’s Flowers: An Exploration of Change and Loss” in June 2022.  I’ve written about it before (see earlier post), but I want to mention it again here in the context of Davis’s article.  All 600 Thoreau herbarium specimens held at Harvard have been digitized.  These images are in the exhibit, presented through the work of several artists.  Davis is highlighting a trend that has become much more common in the 21st century:  the use of herbarium specimens as inspiration for artists.  The great thing about this exhibit is that it remained up for almost a year, was at a popular museum, and highlighted the work of a well-known figure.  It was a wonderful way to introduce herbaria to a wider audience, while also highlighting the changes in the environment in which Thoreau collected.


Armstrong, E. M., Larson, E. R., Harper, H., Webb, C. R., Dohleman, F., Araya, Y., Meade, C., Feng, X., Mukoye, B., Levin, M. J., Lacombe, B., Bakirbas, A., Cardoso, A. A., Fleury, D., Gessler, A., Jaiswal, D., Onkokesung, N., Pathare, V. S., Phartyal, S. S., … Grierson, C. S. (2023). One hundred important questions facing plant science: An international perspective. New Phytologist, 238(2), 470–481.

Davis, C. C. (2023). The herbarium of the future. Trends in Ecology & Evolution, 38(5), 412–423.

Funk, V. A. (2003). 100 uses for a herbarium. American Society of Plant Taxonomists Newsletter, 17(2), 17–19.

Heberling, J. M. (2022). Herbaria as big data sources of plant traits. International Journal of Plant Sciences, 183(2), 87–118.

Manzano, S., & Julier, A. C. M. (2021). How FAIR are plant sciences in the twenty-first century? The pressing need for reproducibility in plant ecology and evolution. Proceedings of the Royal Society B: Biological Sciences, 288(1944), 20202597.

Herbarium Stories: Galls

A. Gall specimens stored in clear plastic folders within a 2-ring binder. B. Gall specimen stored in a cardboard box with no lid. C. Gall specimens stored in an insect drawer. SMNS, Stuttgart (Mertz et al., 2022)

Humans like to organize information into categories to make it easier to deal with.  The problem with the living world is that it’s unruly; some things just defy being put into neat boxes.  Among these are galls, plant structures, often on leaves or stems, formed in response to invasion by another organism.  This is frequently an insect, but other culprits include mites, nematodes, fungi, bacteria, and even parasitic plants.  Usually galls are stored within entomology collections, and thus by the insect species involved.  But any herbarium collection is likely to contain galls, whether they are noted in the label description are not

A recent article describes efforts at the State Museum of Natural History in Stuttgart, Germany to deal with the ecological complexity of galls and also to begin to bring greater order to its 1000-2000 specimen gall collection, most of which was unsorted and kept in three large metal cabinets (Mertz et al., 2022).  Some were on herbarium sheets, many were in paper or plastic envelopes, but there were also specimens in albums, file folders, boxes, and newspapers.  In addition there was an early 19th century collection in drawers, and some galls were in the dried insect collection pinned next to the insects that emerged from them.  The last time the collection had been studied was in 1995, and it had never been completely catalogued.  Every natural history collection is overflowing with specimens, many crying for needed attention, but it makes sense that if no one had been interested in it in nearly 30 years, it would not be on anyone’s priority list. 

It’s thanks to the renewed interest in specimens as sources of biodiversity data that collections like this are now being examined and organized.  Galls, precisely because of their classification complexities, are of more interest at present.  Not only are they objects of botanical and entomological interest, but ecological as well.  The authors of this paper decided to systematically organize the 490 specimens collected in the home state of the institution, Baden-Württemberg, and assess the suitability of the different storage options they encountered.  There was single bound album made in the 1970s with browned and cracking Scotch tape holding down the galls:  not a good option.  Some specimens were in boxes, good for large or oddly shaped items, but not great for saving space.  The galls collected in the 19th century were in insect drawers, which were orderly and kept the specimens safe but again, space hogs. 

Envelopes, on the other hand, provided efficient use of space.  The paper ones kept the specimens secure, but they had to be opened for examination:  time consuming and could lead to damage.  Plastic envelopes allowed visibility, though some deteriorate rapidly.  The same holds for a set of specimens kept on paper in plastic sleeves and stored in a binder.  Finally there were the specimens stored on herbarium sheets.  Interestingly, they were not all of standard size, but they kept the specimens safe, unless they were attached with the dreaded Scotch tape.  It is not surprising that when the team evaluated the storage methods, albums and binders with plastic folders were not deemed viable.  Boxes were only considered appropriate for large items, often the case with galls on fungi. Pinning to trays was superior when drawer space was ample.  Herbarium sheets were optimal for digitization and host plant identification, though not appropriate for large galls.  Also, sheets required “appropriate infrastructure,“ meaning herbarium cabinets, which were different from those usually found in entomology departments.  Envelopes were the best option if space is at a premium.  These recommendations all make sense, and provide a guide for those facing an update of gall collections. 

There were other interesting findings.  Aside from the 19th century collections, no organisms were associated with the other galls studied.  As the authors note:  “It is often possible to determine the gall inducer from the appearance of the gall, but it is preferable to store galls along with their inhabitants. (p. 7)”  Insects were identified as the cause of 72% of the gall specimens.  Because oak galls are conspicuous on leaves and easily collected, they were well-represented.  Though galls were collected throughout the year, August, September, and October were the most common months.  Again, oaks come into play, because this is when their galls would be most obvious on fallen leaves.

In terms of future directions for this work, the article ends with lessons learned including the difficulties in digitization, updating species determinations, georeferencing specimens, and dealing with old place names and other outdated terminology.  The authors added:  “The ultimate arrangement of the gall collection is yet to be determined.  One possibility is to organize galls by host plant, which would facilitate research at the ecological level (p. 9).”  This presents another issue.  Who will identify the host plants?  Where should such a collection be housed:  in the entomology department or in the herbarium?  After all, many herbaria already have lichen collections that are made up of two biological kingdoms, why not have some plants and animals stored together as well?  Or just to put it out there, perhaps in an ecology collection?  Maybe this will be the wave of the future, and a way to get ecologists to become more interested in the specifics of the organisms encountered in their work.  It is at least an option worth considering, especially in institutions like the Stuttgart museum that house multiple collections dealing with many forms of life.


Mertz, A.-K., Awad, J., Wendt, I., Dalitz, C., & Krogmann, L. (2022). Curation and digitization of insect galls in the collection of the State Museum of Natural History Stuttgart. Integrative Systematics: Stuttgart Contributions to Natural History, 5(2), 193–202.

Gardens and Herbaria: Acclimatization and Cultivation

Panax quinquefolius, Mark Catesby, The Natural History of Carolina, Florida, and the Bahama Islands,  Biodiversity Heritage Library

In the age of exploration, growing exotic plants in gardens, botanic or personal, could be a challenge and “acclimatization” became an important goal:  to have a plant from one climate and ecosystem thrive in a different one.  Mary Somerset (see earlier post) did this on a small scale, but to introduce a plant into agriculture or horticulture required much more time and a larger operation.  In 1652, the Dutch created a botanical garden at Cape Town, a trading post for the Dutch East India Company (VOC).  Like many colonial gardens, its function changed over time, as the needs of the colonial government did.  At first, it produced fresh vegetables, mostly European varieties, to supply VOC ships stopping at the Cape.  Later many European and Indian food plants were grown there.  When the garden was enlarged, it had a dedicated space for flowering plants and eventually a program for acclimatizing promising species collected from the parts of Asia involved in Dutch trade.  In the 1690s, Henrik Bernard Oldenland worked for the VOC exploring parts of South Africa and collecting plants.  Later he was superintendent of the Cape Town garden and created a 14-volume herbarium from the plants he collected, especially those he then cultivated in the garden.  It is now at the Geneva Botanical Garden Herbarium (Gunn & Codd, 1981).

Successful cultivation at garden’s like Oldenland’s made more plants available for distribution to other colonies and to the home country.  There were also studies on whether or not related species, or ones that were thought to be related, had similar properties.  This issue arose with a form of cinnamon, now identified as Laurus cinnamomum, found in South America that was ultimately a disappointment to those looking for a new source of the expensive Asian spice from Cinnamomum ceylanicum native to Ceylon, now Sri Lanka (Bleichmar, 2017).  Ginseng from Asia, Panax ginseng, with a root resembling a human form, had been highly prized in Europe for centuries, and when a similar plant, ultimately designated Panax quinquefolius, was found in North America, it spurred the hope that this new supply source would provide ginseng at a greatly reduced price (see image above).  But did it have the same medicinal properties?  For this work, there was no substitute for growing the plants and testing their potency, coupled with herbarium specimens for documenting precisely what was grown.  Eventually, the two plants were deemed different species, though with similar medicinal properties (Stearns, 1970).

The story of Cinchona lancifolia, source of quinine and native to the Andes, is an example of how difficult it was to work out a plant’s chemistry.  The Spanish struggled to learn both to extract the active ingredient from the tree’s bark and to find cinchona varieties that were particularly rich in it.  In 1783, when Spain was seeking to better use their colonies’ botanical resources, the viceroy of New Granada asked one of his governors to supply “skeletons,” herbarium specimens, of the local cinchona trees, ones from which the precious bark was harvested.  The governor was suspicious of this request, judging rightly that the botanists in Bogota, the capital, wanted to compare these specimens with ones from trees they were growing.  There was a great deal of debate about the quinine level in different trees, and even how to measure it, with some arguing for chemical tests, and others seeing medical effectiveness as the only valid measure.  One problem was that there were several species of the Cinchona genus that had varying quinine levels; purification also resulted in unpredictable yields (Crawford, 2016).

While South America was the only source for cinchona worldwide, other countries were attempting to raise the trees in their colonies.  The Royal Botanic Gardens, Kew grew cinchona seeds collected by Richard Spruce, a nineteenth-century British collector.  The garden was also offered seed from a British expatriate living in Peru, Charles Ledger.  Kew turned him down, not knowing the origin of the seeds, but the Dutch were willing to take a chance.  Ledger’s seeds were from what was found to be a different species, now named Cinchona calisaya, that produced more quinine, allowing the Dutch in Java to corner the market until World War II.  While Britain never competed in the international quinine trade, the Kew experiments led to transfer of Cinchona succirubra plants from Kew to Britain’s colonies in Africa and Asia that were plagued by malaria, so they could avoid paying the high Dutch prices (Brockway, 1979).

In the nineteenth century, Kew was center of a network of botanical gardens in British colonies with acclimatization as a major aim.  As with the French and Dutch, some of these gardens had already been founded in the eighteenth century, such as one in Calcutta.  The Calcutta Botanic Garden and others in India were under the control of the East India Company (EIC), a quasi-governmental body ruling large areas of India.  Among the major interests of the EIC was forestry.  Britain had long ago decimated many of its own forests, while its need for lumber continued to expand.  Trees were an important element of economic botany in the colonies.  In India, the exploitation and destruction of forests became so intense, it caused fears of future shortages and also environmental change:  cutting down trees led to changes in local weather patterns, loss of soil fertility, and consequently environmental deterioration in large areas of the country (Noltie, 2016).  Botanic gardens were used as experimental stations to study trees that might be grown on plantations to produce lumber and for reforestation projects.  At one point the Singapore Botanic Gardens focused on growing large numbers of plants, particularly rubber trees, to be distributed throughout the country and to other parts of the British Empire (Barnard, 2016).  In order to document what was grown and to understand the differences among various species and subspecies, herbarium specimens, wood samples, and drawings were collected.


Barnard, T. P. (2016). Nature’s Colony: Empire, Nation and Environment in the Singapore Botanic Gardens. Singapore: National University of Singapore Press.

Bleichmar, D. (2011). Visible Empire: Botanical Expeditions and Visual Culture in the Hispanic Enlightenment. Chicago: University of Chicago Press.

Brockway, L. B. (1979). Science and Colonial Expansion: The Role of the British Royal Botanic Gardens. Interdisciplinary Anthropology, 6(3), 449–465.

Crawford, M. J. (2016). The Andean Wonder Drug: Cinchona bark and imperial science in the Spanish Atlantic, 1630-1800. Pittsburgh: University of Pittsburgh Press.

Gunn, M., & Codd, L. E. (1981). Botanical exploration of Southern Africa. Cape Town: Balkema.

Noltie, H. J. (2016). Indian Forester, Scottish Laird: The Botanical Lives of Hugh Cleghorn of Stravithie. Edinburgh: Royal Botanic Garden Edinburgh.

Stearns, R. P. (1970). Science in the British Colonies of America. Urbana, IL: University of Illinois Press.

Collection Furnishings

Cabinets designed by Mark Dion for the Schildbach wood collection, Kassel Natural History Museum

In the last post on Mark Dion’s artistic commentaries about natural history collections, I failed to mention the many pieces of furniture used in his installations.  In some cases, these pieces were specially designed for displaying collections, such as a cabinet with drawers filled with specimens Dion assembled as part of his Travels of William Bartram—Reconsidered (2008) exhibit, which also included a repurposed old wood-and-glass library cabinet housing a display of alligator-related souvenirs and postcards.  Dion also built cabinets to permanently display the impressive xylotheque or wood library created in the 1780s by Carl Schildbach and now in the Natural History Museum in Kassel, Germany (see image above).  Like paper, which I discussed in an earlier series of posts (1,2,3,4), cabinets are so much a part of herbarium life they are taken for granted unless one of two things happen:  there’s no more room in these, or there are resources available to buy new equipment and/or enlarge a herbarium.

The first is definitely more likely to occur than the second, and the problem usually creeps up slowly.  Sometimes it’s possible to rearrange cabinets and fit in yet another one.  I am thinking specifically of the A.C. Moore Herbarium at the University of South Carolina, Columbia, my herbarium home.  It is composed of a rabbit warren of rooms, all but one with cabinets.  They are all metal, but that’s were resemblances end.  The 19th-century Henry Ravenel Collection, previously at Converse College, is housed in cabinets purchased with a NSF Collections Improvement Grant which funded the majority of the herbarium’s cabinets.  But also interspersed throughout the facility are cabinets of varying vintages and provenances.  Along with the standard-height ones there are several of counter height.  Curator emeritus John Nelson traveled to Washington DC to pick them up when the National Arboretum was disposing of them.  They were well worth the trip.  Bordering on the antique, they are beyond sturdy and double as great work tables.

To me one of the hallmarks of an active herbarium is unmatched cabinets, unless of course an herbarium has been funded, often in part with a NSF grant to buy new furnishings and perhaps move into a larger space, and often equipped with compactors—heaven, but only for a time.  The plants keep coming.  The herbarium at the Royal Botanic Gardens, Kew has been enlarged several times.  However, there is evidence of efforts to make do between additions.  In the oldest building, still with wooden cabinets, there were extra cabinets built on top of the original ones to provide more storage.  The same thing happened at Trinity College Herbarium in Dublin.  A rolling ladder is a necessity with such a setup.  In many herbaria where this hasn’t been attempted, the room on top of the cabinets is where cardboard boxes of unmounted and uncatalogued specimens reside.

Standard herbarium cabinets are hardly suitable for many kinds of collections.  Envelopes of lichens or mosses are often better kept in cabinets with drawers.  Something similar accommodates boxes of slides and vials, the majority of items in the Diatom Herbarium at the Academy of Natural Sciences of Drexel University in Philadelphia.  In the herbarium at the National Botanic Garden in Ireland, there are neatly arranged boxes with pine cones and other large tree-related materials collected by Augustine Henry, co-author with Henry John Elwes of The Trees of Great Britain and Ireland (1906).  His wife hit on the idea of shop boxes used in the clothing stores of the time.  They were sturdy and had cord pulls to make them easy to access.  Many herbaria also have collections of fruits and flowers in jars of solution.  They require a totally different type of care, including a heavier floor to withstand the weight and a door frame with a lip at the bottom, so if there is spillage inside the room, it won’t leak out.

While they are not common in the United States, boxes are used in many herbaria to store herbarium sheets.  Kew uses them in some areas and the National Herbarium of New South Wales in Sydney, Australia does too—they are all red.  Just as there are endless arguments about how kitchen cabinets should or should not be designed, the same is true of herbarium furnishings.  While most herbaria have closed cabinets, often with special seals to keep out pests and moisture, some institutions have open shelves.  The herbaria at the National Museum Natural History in Paris and the Missouri Botanical Garden in St. Louis, both have open shelves in their newer compactor storage facilities.  These are among the largest herbaria in the world, and omitting doors meant less space wasted and greater ease of access.  Since these facilities are temperature controlled and surveilled for pests, this solution seemed the best.

Walking into such spaces sparks a feeling of awe:  a herbarium cathedral.  However, walking into the A. C. Moore Herbarium, gives a different, and perhaps even more wonderful response:  a sense of comfort like entering a home with mismatched, well-used, and well-loved furniture.  In this environment, it is also easier to sense the history that resides there:  the decades upon decades represented and the many places in South Carolina where collections have been made repeatedly, providing data on what has changed over time.  A.C. Moore definitely needs more room, and it would be great to have “a state of the art” facility for the state’s largest collection of South Carolina plants, but I hope one of those old National Arboretum cabinets could also make the move.

Notes: I want to thank Herrick Brown and John Nelson for all their help and their graciousness in allowing me to be part of the A.C. Moore Herbarium family.


Decolonizing Collections

One of James Petiver’s publications where he cited the collectors who provided him with specimens

Over the past year I have spent more time than usual on social media and Zoom presentations.  Since I am interested in plant collections, I tend to come across programs related to natural history museums.  A persistent theme that has gotten even more attention since the rise of the Black Lives Matter movement, is the idea of decolonizing collections.  This is hardly a new concept, but events have made it a more obvious and pressing concern.  Because so many institutions were physically closed, curators and the public had a chance to step back and ask questions about the future of collections and how they are used.

I hesitate to even broach this topic because I am an old, white woman who some would consider privileged:  educated and comfortably retired.  Despite my limit perspective, I am writing about this issue because I can’t not write about it.  One Zoom presentation I attended was sponsored by the Digital Library Federation and featured staff from New York Botanical Garden .  Regina Vitiello, project coordinator for the garden’s Steere Herbarium, discussed the issue of labels with place names that would now be considered culturally inappropriate.  There are a number of issues here ranging from who finds these—is it enough just to wait until someone happens upon a problem or should curators be actively searching for them.  Then, who decides they are inappropriate and what to do about them:  are they expunged—both on the specimen and online—or are they left, but with a notation.  Vitiello notes that this work becomes a communal project within the herbarium, requiring discussions among those responsible for the collection.

Rashad Bell, collections maintenance associate at the NYBG Mertz Library, covered similar issues with the library catalogue.  In searching for items for a patron, he found a 1950 biography of George Washington Carver called The Ebony Scientist, a title that would not even be considered today.  However, the book is still a useful resource, so it should remain in the collection and in the online catalogue.  What, if any, notation should be made on the entry?  Neither Bell nor Vitiello had answers for all the questions they probed, but that is in part what made their presentation useful.  It showed the layers of examination and work involved in actually opening up collections, laying out how they reflect past cultural influences, and what is involved in making them more welcoming to all.

Bell also participated in a presentation at Science Museum Fridays at New York University.  The session was called Decolonizing Living Collections and also included Laura Briscoe, NYBG herbarium collections manager.  After the event,  Bell and Nuala P. Caomhánach wrote about interviews with the participants for the Journal of the History of Ideas blog (1,2).  They are worth reading to get a sense of the complexity of the issues involved.

“Decolonizing collections” can mean many things but a major thrust is to ask new questions of what is available, including what collections and their attendant archives can reveal about the role of indigenous and enslaved peoples in building them.  One collection that is receiving special scrutiny is that of Hans Sloane, the British physician who assembled not only a large herbarium but also books, art, coins, anthropological and zoological materials from around the world, that became the founding collection of the British Museum (see last post).  Sloane’s wealth came in part from his marrying a wealthy widow who had inherited her husband’s Jamaican plantations that employed enslaved people.  Sloane met her while he was physician to Jamaica’s British governor and spent his spare time amassing a natural history collection.  He was aided by British landowners as well as indigenous and enslaved people.  The latter two groups were those most engaged with the land and its organisms (Delbourgo, 2017).  Careful scrutiny of Sloane’s letters and notebooks could reveal interactions and information not recorded in his Natural History of Jamaica.

Sloane’s herbarium is composed of collections by over 280 individuals, with the most specimens coming from James Petiver who himself had acquired 100 herbaria and had a network of collectors around the world.  Important sources were the captains and surgeons on slave ships that sailed a triangular route from Britain to Africa carrying goods that were sold there and then conveying enslaved Africans to be sold in the West Indies and from there in the American colonies.  On the return trip, the ships carried sugar, coffee, and tobacco to Britain.  Though Petiver’s collection had a worldwide scope, the geography of slavery shaped it in that many of his specimens came from West Africa, the Caribbean, and southern American colonies.  The role of slavery here is now being more carefully scrutinized along with other colonization practices (Murphy, 2020).

Petiver published regularly, describing new species that his network had sent him .  He rewarded contributors by mentioning their names in print, but needless to say, the names of many who had actually found the plants and imparted information about them are forgotten.  (see image above)  To me, this is what decolonizing collections is about, attempting to unearth the people and information that never made it into publications.  In most cases, names are lost, but hidden in the archives are references to where collectors obtained plants and plant stories, some of them about a species’ uses or religious significance.


Delbourgo, J. (2017). Collecting the World: The Life and Curiosity of Hans Sloane. Cambridge, MA: Harvard University Press.

Murphy, K. S. (2020). James Petiver’s ‘Kind Friends’ and ‘Curious Persons’ in the Atlantic World: Commerce, colonialism and collecting. Notes and Records: The Royal Society Journal of the History of Science, 74(2), 259–274.

Note:  I would like to thank Ray Pun, instruction/research librarian at the Alder Graduate School of Education in California, for providing the link to the Digital Library  Federation presentation from NYBG.  This is only one of many resources he has pointed me towards and for which I am grateful.

Collections: Lists and Catalogues

A portion of Hans Sloane’s vegetable substances collection, Natural History Museum, London

In writing of Hans Sloane, the great collector of plant specimens and so much more, all forming the foundations of the British Museum, James Delbourgo (2017) argues that Sloane’s greatest legacy as a writer was not his two-volume Natural History of Jamaica, significant though it was, but rather the catalogues he produced for various parts of his collections and the labels he handwrote for so many of its items, including herbarium specimens.  Lists and labels may not seem exciting, but think of all the time, money, and volunteers’ hours that have been expended in the 21st century in digitally transcribing herbarium labels.  And what is a spreadsheet but a glorified list, though at times a very sophisticated one?

Labels and catalogues are what make collections valuable and useable.  A specimen without a label is usually of little if any worth, and unless there is some clue to how a room of specimens is ordered, chaos reigns.  The order may be alphabetical by family, according to the latest Angiosperm Phylogeny Group report (APG IV), or some other system.  In a sense, digital portals such as iDigBio’s or GBIF’s are catalogues on a massive scale and would probably stun Sloane as he thought about all the hours he’d spent inputting data into his catalogues, which were essentially ledger books.

There are no catalogues for Sloane’s herbarium of 265 volumes and 120,000 specimens.  He had an alternate reference system based on the botanist John Ray’s compendium of plants, Historia Plantarum, completed in 1704.  In it, Sloane and his curators noted next to a species entry the volume and page where the specimen of that plant could be found and added species that weren’t described in the text (Dandy, 1958).  Botanists still use this reference to locate specimens.  A copy of Sloane’s two volumes on Jamaica was similarly annotated.  The latter were considered so significant that the names were updated by later botanists, including Daniel Solander who added the names from Carl Linnaeus’s Species Plantarum to keep the reference relevant (Rose, 2018).  When Joseph Banks invited him to join Captain James Cook’s first round-the-world voyage, Solander was also doing something similar for other Sloane specimens, often attaching paper slips with updated names.

Sloane also had a  “Vegetable Substances” collection with 12,000 small, sealed boxes filled with seeds, fruits, and resins, some of medicinal value.  Such a collection is much rarer than the herbarium.  There are written references to botanist’s sharing seeds and other plant materials, but most have not survived.  Analyzing Sloane’s collection, Victoria Pickering (2016) found that about two-thirds of it is intact along with three catalogues, which for most items list who sent the material and what it was used for.  Without the catalogues, determining what was in the boxes would be guesswork at best and there would also be no way to track provenance.  The boxes are just marked with a number, usually corresponding to a catalogue entry.  For example, Pickering was able to attribute 215 items to Mark Catesby, and 160 to James Petiver, who would be receiving them from his numerous contacts.

Sloane’s boxes provide a picture of what was considered valuable, including medicinal substances and seeds.  For collectors like James Cunninghame and Engelbert Kaempfer, the material in the boxes was sent in addition to their specimens.  The seeds may have been viable when they arrived, with some likely given to gardeners of Sloane’s acquaintance who eagerly attempted to grow new finds.  To keep track of things like seeds botanists shared lists of various kinds from the beginning of early modern botany.  Each year, Luca Ghini sent a seed list of what he had collected at the Botanical Garden of Pisa, and his correspondents could, in turn, send lists of those they would like to receive.  The Royal Botanic Garden, Kew’s Millennium Seed Bank grew out of a similar, but much more elaborate seed saving program at Kew.  Lists or catalogues were also common among garden owners as a way to display their prowess in obtaining and cultivating rare and exotic species.  At times these were simply lists of plant names, but sometimes descriptions were included.  Some were publications with illustrations.  That is essentially what Linnaeus’s book on George Clifford’s garden at Hartekamp is.  The illustrations were done by none other than the great botanical artist Georg Ehret.

Another elaborate catalogue, Hortus Elthamensis, was created by Johann Dillenius for James Sherard to describe his garden at Eltham.  The book was 437 pages long and published in two large-format volumes.  Dillenius drew the illustrations of 417 plants on 324 plates, all of which he also engraved.  This was definitely an impressive way to present a rich man’s garden.  James Sherard was the brother of botanist William Sherard of Oxford University.  When William died, he left money for a professorship in botany and arranged for the position to go to Dillenius, who had already come to Oxford from Germany.  Dillenius ends the preface by mentioning his “friend and patron” William Sherard, and this catalogue is definitely a tribute to both brothers.  It also indicates how broad the definition of “catalogue” can be to encompass both a simple list or pamphlet and a two-volume opus.


Delbourgo, J. (2017). Collecting the World: The Life and Curiosity of Hans Sloane. Cambridge, MA: Harvard University Press.

Pickering, V. R. M. (2016). Putting Nature into a Box: Hans Sloane’s “Vegetable Substances” Collection. London: University of London.

Rose, E. D. (2018). Natural history collections and the book: Hans Sloane’s A Voyage to Jamaica (1707–1725) and his Jamaican plants. Journal of the History of Collections, 30(1), 15–33.

Herbaria and Material Culture

Specimen of Coffea arabica with 5 different kinds of paper; Manchester Museum Herbarium, Leopold Grindon Collection

Omar Nasim is an astronomer who writes on the importance of visual inquiry in history of astronomy.  He comes to mind as I write this series of posts (1, 2) on paper because he first came to my attention with his description of how astronomers learned about nebula by drawing them over and over again, getting to know them and in a real sense materialize them on paper (Nasim, 2013).  Since then he has written on the use of photography in astronomical observations.  In a recent article he deals with the photograph from the viewpoint not of the image, but of the substrate on which it is printed.  His perspective is that of material culture, of treating the photo as an object.  Nasim brings up the concept of differentiating between an object and a thing.  This distinction took me some time to sort out (Edwards, 2004).  A photograph is a physical object with an image on it, and it is thing, an entity.  If the image fades to the point of disappearing, there is still a piece of paper, but it is no longer the object it was, though it is still a thing. This approach highlights the fact that a photograph is more than an image, it has physicality.

Once I got my mind around this distinction, I began to think about it in terms of herbarium sheets.  It is not uncommon to read of a collection that was long neglected in an attic or basement.  When finally examined many of the sheets were unsalvageable, that is, the specimens were so rotted as to no longer carry much or any information.  The paper too may have been so damaged by water or lost labels or at least the writing on them.  There was still a thing, but it was no longer the object it had once been.  As I read more about the physicality of photographs, I thought of other similarities with herbarium sheets:  the different kinds of papers they can be mounted on, the ill effects of exposure to light, and the way they can be damaged by  handling:  paper bent, corners missing, stains, and other scars.

Those in natural history museums differentiate between specimens, the remains of living things, and artifacts, human-made objects.  A herbarium sheet is both.  Like a photograph, it is more than just an image, it has physicality both in itself and in its matrix.  In essence, to use a term from the art world, it is a collage.  There is not only the plant but the material such as glue, thread, or linen tape used to affix it to the sheet.  Then there’s the label, and often a stamp with an accession number and the name of the herbarium, perhaps an envelope containing fragments, and one or more determination slips to either verify the name on the label or update it.  There might also be a note concerning the specimen’s provenance or other remarks.  A barcode is a more recent addition, but there can be others:  a map, a sketch or an illustration, or a photograph of the plant in the field.  Some specimens have so much supporting material that it may spill onto a second sheet, as many specimens in Leopold Grindon’s collection at the Manchester Museum Herbarium do.  He liked to append illustrations, journal articles, newspaper clippings to give as full a record of the plant as possible.  The specimen wasn’t enough for him, and really it is never enough.  At least some accessories are essential.

Going through the specimens in a thick species or genus folder may mean encountering different kinds of specimens as physical objects.  There is often an unconscious reckoning of age when holding a specimen.  Some plants have retained their color better than others, and the same may be true of the paper.  It may have yellowed with age, depending upon its composition, may have become brittle, or been blackened by soot or mercuric chloride contamination; it may be thin and flimsy, or thick and stiff.  The plant on a neighboring sheet may have left an imprint or “ghost” on it, if they have been stored together for a long time.  The label is another indication of age, with good penmanship a thing of the past.  And I haven’t even touched on the paper in journals, reference works, and field notebooks, to say nothing of bound ex siccatae, which provide a very different material experience of specimens, somehow more ordered and less intimate.

In writing about the loss of material clues when paper is digitized, Sherry Turkle (2007) compares the experience of looking at the architect Le Corbusier’s drawings on the computer and in the archives:  there is a different sense of scale, a tactile experience, and an awareness of smudges and other signs of use by human beings that doesn’t come through on the screen.  There is also the whole experience of being in the archives—or in a herbarium—surrounded by incredibly informative paper objects.  Many people, including myself, have been separated from specimens over the past months.  Yes, I can see Henry Ravenel’s plants from the 19th century on the A.C. Moore Herbarium website, but it is just not the same as seeing the variety of surfaces on which they are mounted.  Materiality matters!


Edwards, E., & Hart, J. (Eds.). (2004). Photographs Objects Histories: On the Materiality of Images. New York: Rutledge.

Nasim, O. (2018). James Nasmyth’s lunar photography; or on becoming a lunar being, without the lunacy. In C. González (Ed.), Selene’s Two Faces (pp. 147–187). Leiden, NLD: Brill.

Nasim, O. W. (2013). Observing by Hand: Sketching the Nebulae in the Nineteenth Century. Chicago: University of Chicago Press.

Turkle, S. (Ed.). (2007). Evocative Objects: Things We Think With. Cambridge, MA: MIT Press.

Plants and Paper

Conrad Gessner’s Historia Plantarum notebook 1, page 8; University Library Erlangen-Nürnberg

What started me on my exploration of paper, the subject of this series of posts (see last post), was a book review of The Nature of the Page: Poetry, Papermaking, and the Ecology of Texts in Renaissance England by Joshua Calhoun (2020).  The title is intriguing and so was the review (Wilson, 2020).  Needless to say, I bought a copy.  Calhoun is an English professor at the University of Wisconsin-Madison and a Shakespeare scholar.  He is also affiliated with the Nelson Institute for Environmental Studies and at the end of his preface, mentions a limited edition of Aldo Leopold’s environmental literature classic, A Sand County Almanac (1949), that was published in 2007.  It was printed on paper made from pines the Leopold family had planted on their land in rural Wisconsin in the 1930s and 1940s.  Leopold’s words were printed on his plants.

To Calhoun this signifies the fundamental point he wants to make.  What he presents here is a look at the organisms that went into making paper and books; he states bluntly, “paper making is the transformation of a plant” (p. 27).  There are the plants like linen, cotton, straw, and wood used in making the paper itself, but also the wooden boards for bookbinding, and the cloth to cover them.  Also animals were utilized for leather covers and glue for sizing that was applied after the paper was made and dried to make the surface smoother and suitable for writing on with pen and ink.  Since paper is essentially cellulose, it absorbs water, and therefore ink.  Sizing allowed the ink to soak in less.  We are less aware of this today, because we use ballpoint pens with a much less fluid type of ink.  Ink was part of the ecology of paper too.  A common ink was made from oak galls which if properly treated made a good brown ink.  The ink used for printing had oil added, making it thicker and less absorbent than that needed for writing.  As time went on, better sizing was preferred for printing books so that readers could write in the margins.

As mentioned in the last post, botanists used a great deal of paper for writing letters, notes, and labels, so they would be cognizant of the qualities of different papers, and they would have to pay more for the types that were best for recording information.  Calhoun notes that in the early modern era, most paper was made from linen rags.  While the Chinese had mastered techniques to convert plant material, most successfully from the mulberry tree, directly into paper, Europeans didn’t accomplish this with the species at hand until the 19th century.

Linen rags were cut into pieces and fermented to loosen the structure of the cloth and separate the fibers.  Since the major constituent of paper is cellulose, other matter had to be removed in part by fermentation.  The resultant slurry was poured into a rectangular wood frame, with a bottom of mesh.  Water was pressed out through the mesh while the slurry is thick enough and the fibers overlap enough to remain in the frame.  The damp sheets were then hung up to try and later, further flattened and smoothed.  Adding sizing was another wet, messy process that resulted in loss of sheets that become misshapen or otherwise damaged.  Sizing made it possible to write on paper, and the glue adhered the fibers more firmly to each other resulting in stronger, more durable paper.  Unsized paper was okay for wrapping packages and other rough and ready uses, including pressing specimens since it readily absorbed water.

Calhoun goes into some length on how paper in books sometimes retained part of its their earlier history.  There is a book history term, shives, for pieces of flax husk that were sometimes inadvertently introduced into the paper slurry.  In some cases, small pieces of linen cloth, including linen sails, ended up on a page.  Flecks of organic matter from the river water used in papermaking were also at times apparent, another link to the environment.  He includes photographs of several pages from early editions of Shakespeare’s works as examples of these inclusions.  He also quotes from several 16th and 17th-century poets who refer to such additions in their works as indicating that users of paper were familiar with its properties and oddities.

Toward the end of the book, Calhoun deals with present-day ecological issues relating to books, not so much in terms of the consequences of cutting down forests to make paper, but the possible long-term future of books in the face of global warming.  His outlook is bleak.  He writes that the best libraries for all books, but particularly the old and precious ones, are those with strict temperature controls.  Keeping books at low temperatures slows chemical deterioration and prevents fungal and insect damage.  He makes the interesting point that there are two kinds of “bookworms,” one that creates round exit holes and the other oval ones.  Also, there are any number of fungal species that can destroy paper.  Calhoun speculates that in the future, it may not be possible to maintain climate-controlled conditions as fuel become scarcer and more costly.  He notes that “books are made of once living material that is slowly decomposing.  Deterioration is a natural process” (p. 130), a reminder of the organic origins of paper and of the fragility of herbaria, where plant specimens and their supporting material are both subject to predation by bugs and fungi.


Calhoun, J. (2020). The Nature of the Page: Poetry, Papermaking, and the Ecologies of Texts in Renaissance England. Philadelphia: University of Pennsylvania Press.

Leopold, A., Schwartz, C. W., Bradley, N. L., Leopold, A. C., & Leopold, E. B. (2007). A Sand County almanac: And, sketches here and there. Baraboo, WI: Land Ethic Press.

Wilson, G. (2020, Sept. 4). The Nature of the Page by Joshua Calhoun book review. TLS.

Looking at Paper

Alisma plantago-aquatica specimen, Ulisse Aldrovandi herbarium at the University of Bologna’s Botanic Garden

I’ve been writing posts on herbaria for over four years and I’ve never discussed the use of paper in botany.  Considering the pivotal role paper has long played in the preservation and documentation of plants, this seems a gross oversight.  To make amends, this series of posts will deal with several aspects of paper’s relationship to plant collections.  First, a little history.  The Chinese created the earliest known paper from hemp in the first century BC; this was a relatively crude product used more for packing than for writing.  They refined their processes in the following centuries, and once mulberry was used in the 7th century, it became the raw material of choice.  Papermaking spread at that time to Japan and then on to the Middle East with the first paper factory in Baghdad opening in 794 (Weber, 2007).  Paper spurred the development of science and literature in the Islamic world and led to the first papermaking in Spain in the 11th century, from there it reached Italy in 1235, Germany in 1391, and England a century later (Basbanes, 2013).  Around 1450 when Johannes Gutenberg produced the first book printed with movable type, he ordered paper from Italy because of its smoothness and ability to take ink better than the German product.

In parts of Europe, paper was not a very old technology when the first herbaria were created, probably in the 1520s in Italy.  But by this time, the demand for paper for book printing led to much higher production rates, a greater variety of grades, and an increase in the uses to which paper was put.  In the 16th century, it was still an expensive commodity, but it was much cheaper and more available that parchment, made from animal skins, that had been the material of choice for important manuscripts and documents, even after the introduction of paper.  In her seminal work on early-modern printed herbals, Agnes Arber (1938) thought it curious that pressing plants wasn’t introduced earlier since pieces of fabric or thin sheets of wood could be used in place of paper and put it down to a lack of ingenuity.  By the time modern botany had begun to emerge in the first half of the 16th century, paper was becoming more familiar commodity and the rough type used to packaging would serve in drying plants.  In fact, it was more absorbent than papers that were sized, that is, coated with something like animal glue or gelatin to create a smoother surface and more receptive to printer’s ink.

But botanists weren’t just using paper to press and preserve plants, but were writing letters, taking notes, and making lists of plants in their gardens or encountered on field trips.  As Valentina Pugliano (2012) notes, lists were “among the new tools at the naturalist’s disposal for dealing with a scientific world increasingly populated by objects” (p. 716).  Luca Ghini, purported by some to be the creator of the first herbarium but definitely one of its key proponents, sent out seed lists each year from the Pisan botanical garden which he directed (Findlen, 2017).  His correspondents could request any of the listed seeds for planting, and some probably then made specimens of their own from the plants.  The seeds themselves were usually wrapped in paper, and Ghini was also known for sending portions of his herbarium to colleagues along with notes and drawings or prints as ways to communicate about plants.

Ghini’s protégé and his successor at the University of Bologna, Ulisse Aldrovandi, used paper on a large scale.  There are 15 volumes of his herbarium still extant and over 80 volumes of notes.  He developed a paste to adhere specimens to paper, and he also used it to paste slips of paper as additions to his notes.  The slips could be shifted to where the information might be more relevant.  This system was also used by Conrad Gessner in Switzerland and later by Carl Linnaeus when he added information to his Species Plantarum that was interleafed with blank pages.  Slips had the advantage of mobility when ideas were uncertain.  All this seems mundane to us, but these tools were being developed as botanical knowledge burgeoned and must at times have seemed unmanageable (Müller-Wille & Charmantier, 2012).

A number of botanists, such as Felix Platter, filed illustrations along with specimens in notebooks.  His are now in the Bern City Library and can be viewed on the web.  He often pasted a plant on the right-hand side and a print, drawing, or both on the left, with each supplementing the information in the other.  He also made the most of the images he had.  He somehow acquired the original watercolors by Hans Weiditz that were used to make the woodcuts in for Otto Brunfels’s classic 1530 herbal, one of the first printed herbals with naturalistic illustrations.  Weitz made the best use of his paper by painting on both sides of a sheet.  Platter didn’t want to sacrifice either image, so he cut around them, and pasted the cutouts across from their respective plants.  In most cases, the pieces were substantial enough to be useful, and perhaps the least successful were discarded.  This is a reminder both of how precious paper was and how ardent botanists were in trying to document plant information (Benkert, 2016).


Arber, A. (1938). Herbals: Their Origin and Evolution a Chapter in the History of Botany, 1470-1670 (2nd ed.). Cambridge: Cambridge University Press.

Basbanes, N. A. (2013). On Paper: The Everything of Its Two-Thousand-Year History. New York: Knopf.

Benkert, D. (2016). The ‘Hortus Siccus’ as a Focal Point: Knowledge, Environment, and Image in Felix Platter’s and Caspar Bauhin’s Herbaria. In S. Burghartz, L. Burkart, & C. Göttler (Eds.), Sites of Mediation (pp. 211–239). Leiden, NLD: Brill.

Findlen, P. (2017). The death of a naturalist: Knowledge and Community in Late Renaissance Italy. In G. Manning & C. Klestinec (Eds.), Professors, Physicians and Practices in the History of Medicine (pp. 127–167). New York: Springer.

Müller-Wille, S., & Charmantier, I. (2012). Natural history and information overload: The case of Linnaeus. Studies in the History and Philosophy of Biological and Biomedical Sciences, 43, 4–15.

Pugliano, V. (2012). Specimen Lists: Artisanal Writing or Natural Historical Paperwork? Isis, 103(4), 716–726.

Weber, T. (2007). The Language of Paper: A History of 2000 Years. Bangkok: Orchid.