Nature Prints as Art

4 Eden

Announcement for Propagating Eden exhibit at Wave Hill, Bronx NY

I firmly believe that art and science can’t be separated, and that this is particularly true in botany.  Plants are simply beautiful, and that beauty has attracted many people to study them more closely, even in this age of “plant blindness.”  For some, nature printing has become an absorbing hobby, with the Nature Printing Society having several hundred members.  It publishes a newsletter that focuses on techniques as well as reviews of published works with nature prints.  The Society has also produced an informative guide to nature printing, not only of plants but of animals as well, particularly fish (Huffman, 2016).  For the latter, the primary technique is Japanese gyotaku that creates stunning works that even a botanist could love.

Since I’m interested in the fabric arts, particularly quilting and embroidery, I’ve gotten a couple of books on nature printing on fabric as well as paper (Bethmann, 2011; Dahl, 2002).  I’ve used the technique just enough to know that, like creating herbarium specimens, there is quite a bit of expertise involved that only practice will make anywhere near perfect.  However, the basic idea is simple; it’s something that a child can do with a sturdy leaf covered with marker ink on one side and pressed on a sheet of paper.  There is a magic to this because it’s a way to make venation a focus of attention.  I keep coming back to the Mabey (2015) quote with which I began this series of posts to the effect that no technique can capture the essence of a plant perfectly.  However, nature printing can very effectively highlight certain aspects of that essence.

Several years ago, there was an exhibit at the Wave Hill estate in the Bronx, NY on nature printing in botany and art.  It was there that I fell in love with the technique because this rather small exhibit captured the history of nature printing so thoroughly.  It included some of the earlier works that I’ve already cited such as those of Franklin, Atkins, Auer, and Bradbury.  But what really grabbed my attention were the various ways in which 20th and 21st-century artists have employed nature printing.  Kiki Smith was represented by a lithograph with pressed leaves.  Another striking example was Ed Ruscha’s Clock of 1994 with what appears to be dried grass glued to the page, but is actually a print made by a proprietary technique called Mixografia, a relief color printing process.

In conjunction with this exhibit, there was a symposium on several aspects of nature printing:  Karen Reeds (2006) spoke on the technique’s history, including her research on Leonardo Da Vinci’s role, Patricia Jonas compared nature prints with herbarium specimens, and Michele Oka Doner described using nature prints in her art.  In the show was a striking Doner print of what looked like the tree of blood vessels in the lungs, but was in reality a print made with roots of banyan trees that she collected from the beach near her Florida home.  This work a beautiful example of how branching patterns are ubiquitous in nature, as are her massive prints of the human body.  As an aside, I have to add that several months later I encountered her work again, this time at the Frederik Meijer Gardens and Sculpture Park in Grand Rapids, MI.  Doner designed the floor of the visitor’s center—an installation called Beneath the Leafy Crown (2009)—with 1600 “prints” of plants and invertebrates done in bronze and embedded into terrazzo (Becherer, 2010).

In his extensive historical review of nature printing, Roderick Cave (2010) cites other nature printers who were artists rather than botanists.  Most notable is the surrealist Max Ernst who used what he called frottage:  making rubbings from the surface of wood or other materials, especially in his series Histoire naturelle of 1926.  Arthur Rushmore, an American print maker, developed his own technique for creating what he called “hay prints,” which influenced later artists.  The British artist Morris Cox also employed prints imaginatively, combining them with his poems.  Some are quite fanciful, such as a human figure of printed grass, others are more reminiscent of 19th-century colored prints of flowers.  He sometimes also included a favorite subject of earlier printers: lace.

I want to end with the work of one of my favorite contemporary nature printers, one who unfortunately passed away shortly after publishing an amazing book that I mentioned in an earlier post on xylaria and tree rings.  It’s Woodcut by Bryan Nash Gill (2012), a collection of, quite literally, wood prints.  Gill would cut a slice through a tree trunk, meticulously sand it, apply ink, and make relief prints of the wood’s raised grain.  He printed not only cross sections of trunks, but cuts through milled planks as well, often juxta-positioning them in interesting patterns.  His works are definitely in the realm of art not science, but for the botanist they are still wonderful reminders of the beauty and mystery beneath the surface of a tree, beneath the bark.  This reminds me, that bark, too, can be a subject for the nature printer, and this will be my next art project.  I doubt that it will result in a great work of either art or science, but I am sure I will learn something more about the printing process and about the wonders of bark texture.


Becherer, J. (2010). Michele Oka Doner. Grand Rapids, MI: Frederik Meijer Gardens and Sculpture Park.

Bethmann, L. D. (2011). Hand Printing from Nature. North Adams, MA: Storey.

Cave, R. (2010). Impressions of Nature: A History of Nature Printing. London: British Library.

Dahl, C. A. (2002). Natural Impressions. New York, NY: Watson-Guptill.

Gill, B. N. (2012). Woodcut. New York, NY: Princeton Architectural Press.

Huffman, S. (2016). The Art of Printing from Nature: A Guidebook from the Nature Printing Society. Lake Shore, MN: Nature Printing Society.

Mabey, R. (2015). The Cabaret of Plants: Forty Thousand Years of Plant Life and the Human Imagination. New York, NY: Norton.

Reeds, K. (2006). Leonardo da Vinci and botanical illustration: Nature prints, drawings, and woodcuts ca. 1500. In Visualizing medieval medicine and natural history, 1200-1550 (pp. 205–237). Burlington, VT: Ashgate.


Nature Printing in the 19th Century

3 Bradbury Fern Plate 1

Plate 1 from The Ferns of Great Britain and Ireland.

Another name for nature printing is self printing because it is the inked plant itself that makes the print, rather than an artist creating marks on paper, independent of the specimen.  However, ink isn’t necessary, sometimes light itself can work, as when a plant is set down on photosensitive paper and then exposed to light.  That was how Anna Atkins produced cyanotypes of algae such as the one above (Armstrong & de Zegher, 2004).  Her first book of these is argued to be the earliest publication of any form of photography (1843-1853).  Atkins produced 400 plates in 11 years, but the process she used required a unique exposure for each copy, so it’s no surprise that there are less than a dozen copies of this work (Bridson & Wendel, 1986).  Such a project was obviously labor intensive, and over the years several printers attempted to devise ways of increasing the number of prints from one plant.  As mentioned in the first post in this series, Benjamin Franklin managed to make impressions in soft lead, but the technique was still time-consuming and messy.  Roderick Cave (2010) describes this and many other attempts in his book on nature printing.

In terms of output, the most successful nature printing technique was that developed by Alois Auer, who became director of the Austrian National Printing Office in 1841.  He experimented with gutta-percha (a gum with some properties similar to soft plastic) to make prints of fish and then create an electrotyped copy from it.  Electrotyping means employing an electric current to lay down a thin layer of copper on the print.  The copper is set on a harder metal background and used for the actual printing; it is much more durable than the original print.  However, the gutta-percha prints often looked messy.  The next approach was to pass specimens through a rolling press between plates of polished lead and steel.  This made a cleaner impression in the lead, which could then be used to create an electrotype copy.  Several large-scale botanical projects employed the method, often using colored inks.  Some of the most successful were of algae.  As I have described in an earlier post, collecting and studying seaweeds were popular pastimes in the mid-19th century, particularly among women.  Anna Atkins’s work is one indication of this.  When properly prepared, either as specimens or nature prints, seaweeds were beautifully delicate.  Since they were plants without flowers, which often didn’t print well, the prints were satisfying even when produced in a single color.  However the Auer method was also used on higher plants.  The Imperial Printing Office’s largest project produced five folio volumes of nature prints of Austrian plants (Ettingshausen & Pokorny, 1856-1873).

Auer, who had a patent on his process, was not without competition.  Carlo and Agostino Perini  created a Flora of Italy, over a span of 11 years (1854-1865) using Auer’s method, but production costs were high.  Henry Bradbury, the son of an established British printer, asked Auer if he could visit Vienna and learn about the process.  Auer agreed and was apparently quite forthcoming in showing Bradbury how the printing was done.  Upon his return to England, Bradbury took out a patent on what he claimed was a different and better technique, but Auer argued that the process was essentially the same as that used in Vienna.

A great deal of acrimony developed between Auer and Bradbury, but in the meantime, Bradbury published a few of the most impressive works in the history of nature printing.  First there was A Few Leaves Represented by Nature Printing, a brief, relatively inexpensive folio to show off the method.  The Bradbury printing style accentuated the venation of the leaves, making them seem almost transparent, an attribute that many botanists saw as misleading.  The most spectacular Bradbury publication was the large folio format The Ferns of Great Britain and Ireland (see figure above).  I have seen a copy of Ferns in the library of the Delaware State University herbarium, and it is indeed a wonder to behold.  Like ferns seaweeds seem to lend themselves to the technique, and Bradbury created a multi-volume work on algae that is spectacular in its display of beautiful forms and colors, but wasn’t as popular as the fern book.  The seaweed publication marked the end of this particular chapter in nature printing since Bradbury committed suicide in 1860.

At least a few 19th-century botanists found nature printing a useful way to document plants in the field (see last post), and there were also a few who used prints in their publications.  Not surprisingly the latter were mostly Austrians who published through Auer’s Austrian National Printing Office.  Constantin von Ettinghausen was interested in paleobotany and employed the technique in his publications for over 40 years.  He found nature printing skeletal leaves a good way to compare living plants with fossils and used the technique in his publications for over 40 years.

Despite Austrian expertise in the field, the most massive nature printing project was produced in France.  Herbier de la Flore Française (Cusin & Ansberque, 1867-1876) ran to 26 volumes with over 5,000 plants, however the printing technique used for these books created what Cave calls “rather dull” plates (2010, p. 147).  He cites many other interesting types of nature prints, including their use in decoration during the height of another 19th-century plant-related fad:  fern mania.  This brings to the fore the aesthetic appeal of nature printing that becomes the dominant focus in 20th and 21st-century printing projects, which will be the subject focus of my final post in this series.


Armstrong, C., & de Zegher, C. (2004). Ocean Flowers: Impressions from Nature. Princeton, NJ: Princeton University Press.

Atkins, A. (1843). Photographs of British Algae: Cyanotype Impressions (5 volumes).

Bridson, G. D. R., & Wendel, D. E. (1986). Printmaking in the Service of Botany. Pittsburgh, PA: Hunt Institute for Botanical Documentation.

Cave, R. (2010). Impressions of Nature: A History of Nature Printing. London: British Library.

Cusin, M. L., & Ansberque, E. (1868). Herbier de la flore française. Lyon: s.n.

Ettingshausen, C., & Pokorny, A. (1856). Physiotypia plantarum austriacarum: Vienna, Austria: Imperial Printing Office.

Perini, C., & Perini, A. (1854). Flora dell’Italia. Trento, Italy: Tipografia Perini.

Nature Prints as Botanical Documents

Nature print of Cassia by Thomas Horsfield at the

Nature print of Cassia by Thomas Horsfield at the Academy of Natural Sciences of the Drexel University, Archives and Manuscript Collection #625

Alexander von Humboldt and Aimé Bonpland are justly famous for their five-year exploration (1799-1804) of parts of South and Central America as well as the Caribbean.  They brought back thousands of plant specimens as well as rocks, fossils, and the remains of animals.  Also in the haul sent to Paris were over 200 nature prints that weren’t given much attention before the 21st century.  Even the two explorers said little about them in their journals and letters, though they did annotate them.  For several years after their return, Bonpland worked on the plant collection in conjunction with Humboldt and the German botanist Carl Kunth at the Natural History Museum in Paris.  In 1816 Bonpland decided to return to South America, taking the plant specimens with him; they were only returned to Paris 1858.  However, Kunth managed to catch up with Bonpland in La Havre before he sailed and retrieved six volumes of field notes and the nature prints.  Kunth used these reference materials in identifying some of the species Humboldt and Bonpland had discovered.  Before Kunth returned to Germany in 1829, he donated the prints to Benjamin Delessert, a wealthy amateur botanist, whose heir in turn gave them to the Institut de France where they remain.  They were highlighted in an exhibit about Delessert in 1993, and this was how the Austrian botanical historian H. Walter Lack came to know of them and write an article on them (2001).

It seems that Humboldt and Bonpland were driven to make nature prints because they lost so many herbarium specimens.  Lack quotes from a letter Humboldt wrote to the botanist Carl Willdenow in Berlin:

“Alas, almost in tears we open our plant boxes.  Our herbaria have the same fate lamented already by Sparman, Banks, Swartz and Jacquin.  The immense wetness of the America climate, the rankness of the vegetation, which makes it difficult to find fully grown leaves, have destroyed one third of our collection.  Every day we find new insects which destroy paper and plants.  Camphor, turpentine, tar, pitched boards, hanging boxes fixed on ropes in the open, all tricks devised in Europe fail here, and our patience has become tired.  After being absent for 3-4 months you hardly recognize your herbarium, you have to discard 5 out of 8 specimens (p. 220).”

Since the paper Humboldt and Bonpland used for printing had Spanish watermarks, they likely didn’t originally plan to make prints and didn’t take printing supplies with them, but bought some in the Spanish colonies they visited.  Though they were probably both involved in printing, Bonpland, whose specialty was botany, likely took the lead.  Most of the annotations are his, with a number in Humboldt’s handwriting.  The pair were among the first collectors to number their specimens and numbered the prints in the same series with the plants themselves.  The numbers indicate that prints were made over a long period of time—perhaps after a spate of specimens were lost their frustration level would again mount and lead to more printing.  Many of the prints are annotated by Kunth; he gave them determinations that were then published in the Nova genera et species plantarum.

As Lack notes at the end of his article, the use of prints by botanists remained an “isolated phenomenon,” but it wasn’t a unique one.  The American naturalist Thomas Horsfield made prints during the almost 20 years (1801-1819) he spent in Java as a surgeon working for the East India Company (EIO).  Collecting was his passion and his botanical prints were one manifestation of this.  I have written about them in a previous post, but they should be mentioned here for two reasons.  First, they are of amazingly good quality.  Roderick Cave (2010), an expert on nature prints, considers them among the best he has ever seen, which is high praise indeed.  One reason for the quality is that Horsfield used softer Chinese paper rather than firmer European paper.  Horsfield, or perhaps an assistant, inked both sides of each specimen, folded a large sheet around it, and burnished it from the back, making mirror-image prints.  One bound set of prints are at Drexel University’s Academy of Natural Sciences Library, and I’ve been fortunate enough to examine them.  Their delicacy and detail are exquisite, and the quality is consistent throughout the collection.  The book is accompanied by an index of the plants, most with at least a genus name given and in some cases the Javanese name as well; the arrangement is Linnaean.  This is one of three known copies; the other two are in England (Peck, 2014).

The other reason for mentioning Horsfield is that like Humboldt and Bonpland, he was driven to nature printing because of the difficulties in preserving specimens, though, like them, he sent thousands of specimens back to London, to his employer’s headquarters.  He eventually went to England and spent the rest of his life in the employ of the EIO working on its collections and writing up his results (Horsfield, 1990).  Along with John Bennett and Robert Brown, he published Plantae javanicae rariores (1838-1852) documenting his botanical discoveries.  The illustrations are in part based on the prints as well as on his specimens.  Here as with Humboldt and Bonpland, nature prints made a significant contribution to important works on exotic flora.  While this is only a drop in the ocean of botanical publications, it deserves attention.  In the next post, I’ll examine how botanical nature printing developed later on in the 19th century when it had its greatest influence.


Bennett, J. J., Brown, R., & Horsfield, T. (1838). Plantae Javanicae rariores. London: Allen.

Cave, R. (2010). Impressions of Nature: A History of Nature Printing. London: British Library.

Horsfield, T. (1990). Zoological Researches in Java, and the Neighboring Islands. Singapore: Oxford University Press.

Lack, H. W. (2001). The plant self impressions prepared by Humboldt and Bonpland in tropical America. Curtis’s Botanical Magazine, 18, 218–229.

Peck, R. M. (2014). Discovered in Philadelphia: a third set of Thomas Horsfield’s nature prints of plants from Java. Archives of Natural History, 41(1), 168–170.

Botanical Nature Prints: An Introduction

Print of Campanula by Zenobe Pacini in the Bibliotheque Nationale de France

Nature print of Campanula by Zenobe Pacini in the Bibliothèque nationale de France

Creating a herbarium specimen is an attempt to pin a plant down, to capture it on a page.  Obviously, this aim is only semi-successful.  The plant is physically present, but the life has gone out of, as has much its dimensionality and color.  Still, it contains a great deal of taxonomic information, and often DNA and other diagnostic chemicals.  Visiting a plant in the field may be impractical as is propagating every plant under study; photographs can document form and dimensionality, but they have no DNA, nor do botanical illustrations, which are time-consuming to produce.  In other words, there’s no perfect way to capture a plant.  As Richard Mabey (2015) writes:  The quintessence of a plant can only ever be a fantastic goal, something to travel towards but never reach (p. 27). But there is another answer, though again it isn’t a perfect solution.  That is the nature print, the subject of this set of posts.

Usually, a nature print of a plant involves inking one or both sides of a flattened specimen, sandwiching it between pieces of paper and applying enough pressure, either by hand or instrument, to transfer ink from plant to paper.  The process definitely has severe limitations, which is why it’s not part of most botanists’ repertoire.  Details of flower structure usually don’t show up well nor do any thick or fleshy plant parts.  Still, it can produce fascinating results, such as the prints I saw in an anonymous collection of prints at Oak Spring Garden Library (Tomasi & Willis, 2009).  It was created in Britain in the early 1700s by some avid plant collector, probably an amateur, yet one who could identify the common names for each of the specimens in a carefully created index at the beginning of the book.  While here the emphasis was on leaves, other printers included, or tried to include, stems and flowers, which often didn’t print as well.  The Oak Spring Garden Library also has a published nature print book by Christian Gottlieb Ludwig from 1760.  It has beautiful prints that have been colored, but the flowers are mostly painted in with rather stylized forms (Tomasi and Willis, 2009).  If nature printing results were often imperfect, why did the technique come into rather frequent use in the 16th century, reach an apex in the 19th, and still be popular at least among artists and amateurs into the 21st?

Answers to this question can be found in the best book I’ve seen on the subject, Roderick Cave’s (2010) Impressions of Nature: A History of Nature Printing.  He cites a print from as early as 1320 and also discusses Leonardo Da Vinci’s description of the technique, which was accompanied by a print of a single sage leaf.  As botany developed into a science in the 16th century, some of those who documented plants with illustrations and herbaria also created nature prints.  These include Conrad Gessner, Thomas Kentmann, Felix Platter, and Fabio Colonna.  There is evidence that at least the latter used prints as references in creating the illustrations for his book.  Among the most magnificent prints from this time are found in the 1520 volume created by the pharmacist and perfumer Zenobe Pacini, who enhanced the prints by coloring them and adding details in watercolor.  In the 17th century, the work of Paolo Bocconne is also remarkable; his prints are now available online and well worth examining.

It’s likely that it was Bocconne who brought the technique to England and perhaps taught it to the avid botanist, William Sherard, whom Cave suggests passed it on to his colleagues.  In the 18th century, the Spanish explorer Joanne Garcia de Chaves y Guevara, made nature prints of the plants he found in California (Cave, 2010).  And on the east coast of North America, Benjamin Franklin, who may have learned the technique in Britain, worked with Joseph Breintnall to use leaves in creating currency.  Since it would be difficult to copy the venation of a leaf precisely, they devised a way to transfer the leaf impression to type metal for printing money.  Breintnall also sold leave impressions as references for amateur botanists; he leaves he at John Bartram’s farm on the outskirts of Philadelphia.  Farther north, Jane Colden, a botany enthusiast as was her father Cadwallader Colden, created over 300 nature prints of native plants she found growing near their farm in New York State.

The Coldens were serious about the study of native plants and printing was Jane Colden’s means of documenting at least something of what these plants looked like.  It was more efficient than trying to draw them all, though she did do illustrations as well.  Nature printing was a way to hold on to something of a plant after an encounter with it.  The British notebook at Oak Spring Library that I mentioned earlier is one example of this, as is another from Germany, also anonymous but created later, in 1824 (Tomasi & Willis, 2009).  Bound into the manuscript is a pamphlet published in 1797 by Johann Friedrich Korn that presents prints of tree leaves and also describes how to make prints (Raphael, 1989).  This suggests the process was popular enough that publishers sought to profit from the interest.

While some amateur and professional botanists created herbaria, others chose to make prints or to use a combination of techniques.  For over 50 years, John Jacobs Thomas kept a notebook, now at New York Botanical Garden, recording 367 apple varieties as well as a number of other fruits (Fraser & Sellers, 2014).  For some of these, he included prints of cross sections.  In one of his field note books, the USDA botanist David Griffiths, who was exploring in the Southwest US, made prints of prickly pear fruits to document their differences.  In both cases, the prints served the serious purpose of recording what measurement along could not, and doing this for fruits that would have been difficult to preserve on a herbarium sheet.  In the next post, I will discuss botanists who were led to create nature print collections for other reasons while exploring remote parts of the world.


Cave, R. (2010). Impressions of Nature: A History of Nature Printing. London: British Library.

Fraser, S. M., & Sellers, V. B. (Eds.). (2014). Flora Illustrata: Great Works from the LuEsther T. Mertz Library of the New York Botanical Garden. New Haven, CT: Yale University Press.

Korn, J. F. (1797). Sammlung von 50 in Kupfer. Breslau: Hirschberg und Liss.

Ludwig, C. G. (1760). Ectypa vegetabilium usibus medicis. Halae Magdeburgicae.

Mabey, R. (2015). The Cabaret of Plants: Forty Thousand Years of Plant Life and the Human Imagination. New York, NY: Norton.

Raphael, S. (1989). An Oak Spring Sylva: A Selection of the Rare Books on Trees in the Oak Spring Garden Library. Upperville, VA: Oak Spring Garden Library.

Tomasi, L. T., & Willis, T. (2009). An Oak Spring Herbaria: Herbs and Herbals from the Fourteenth to the Nineteenth Centuries. Uppervil

The Nature Prints of Thomas Horsfield

Loranthus nature print from #625 in the Archives and Manuscripts Collection of the Academy of Natural Sciences of Drexel University

Loranthus nature print from #625 in the Archives and Manuscripts Collection of the Academy of Natural Sciences of Drexel University

Last summer, I visited the Academy of Natural Sciences in Philadelphia, which is now part of Drexel University.  Of course, I stopped in the gift shop, and I was drawn to note cards with nature prints on them: it was the delicacy of the prints that had caught me eye.  The information on the back indicated that they were from a volume of nature prints in the ANS Library.  They were done by Thomas Horsfield (1773-1859) in Java in the early part of the 19th century.  I didn’t have time to look at them that day, but several months later when I was again in Philadelphia, I made an appointment to see the prints.  Needless to say, the originals are even more impressive.  They are very fine, with all the veins and even flower forms carefully delineated.  In an effort to find out more Horsfield and the prints, I recently looked at a copy of the 1990 reprint of Horsfield’s Zoological Researches in Java and the Neighboring Islands; it includes a biographical essay on Horsfield by John Bastin, Emeritus Reader in the Modern History of South-East Asia at the University of London.

Horsfield was born in Pennsylvania, studied with a pharmacist, and then received a degree in medicine from the University of Pennsylvania.  He served as surgeon on a merchant vessel that sailed to Java, and when he returned home, he decided to go back to Java to study its natural history.  In 1801, he equipped himself and when in Java he gained support from the Dutch government for his explorations.  Because of his medical background, his main interest was in finding medically useful plants, but he collected widely and studied the geology of the region as well.  Over time, he became more and more interested in animals, especially after the British under Sir Thomas Stamford Raffles took over the administration of Java and Horsfield received support from the East India Company (EIC).

When he left Java in 1819, he went to England to continue his natural history work for the EIC.  He worked on his collections and eventually served as curator at the EIC’s museum.  By this time he had also gained the interest of Joseph Banks who was impressed by Horsfield’s plant collection and by the nature prints of over 400 plants that he had produced.  In an earlier letter to Raffles, Horsfield had explained that since herbarium specimens often rotted in the tropics he decided to make prints as a way to document plant features.  He applied ink to both sides of the specimen, folded a thin sheet of Chinese paper around it, and then burnished it.  This gave surprisingly good print of both sides.  In fact, Roderick Cave, the author of Nature Prints, writes that these are some of the best prints he has ever seen.  So there was a very good reason they caught my eye in the ANS gift shop.  There are three known copies of the prints, one at the Natural History Museum, London, one at the British Library, and the ANS volume, which was purchased by a Philadelphian and given to the library (Peck, 2014).

Horsfield, T. (1990). Zoological Researches in Java and the Neighboring Islands. Singapore: Oxford University Press.
Peck, R.M. (2014). Discovered in Philadelphia: A third set of Thomas Horsfield’s nature prints of plants from Java. Archives of Natural History, 41(1), 168-170.

Detail of Loranthus nature print from #625 in the Archives and Manuscripts Collection of the Academy of Natural Sciences of Drexel University