Scientific Illustration

Illustrations for a Tropical Flora

by Bobbi Angell
Originally appeared in The Botanical Artist, Number 13


As a freelance illustrator associated with The New York Botanical Garden (NYBG), I began work on a project in 1988 that was recently published, and I thought I’d outline the procedures involved in my contribution to A Guide to the Vascular Plants of Central French Guiana. 

NYBG botanist Dr. Scott Mori has made over 25 extensive trips to French Guiana to prepare a guide to the native and naturalized plants of the region, encouraging their preservation as a biological preserve. I had worked for Dr. Mori on small projects before, so I didn’t think to ask many questions about the scope of this project when I accepted specimens to illustrate for a new flora. The number of illustrations and the time frame were undetermined, but we figured it would be approximately 200 full-page plates, prepared over several years. As with all my projects, I would have dried, pressed herbarium specimens, pickled flowers (preserved in alcohol) and photographs if available, and species descriptions. It was up to me to determine what aspects of the plants I would depict, and to design an artistically pleasing composition with an emphasis on scientific accuracy. Complete stages of growth, from vegetative to flowering to fruit, were to be illustrated if possible. Priority was given to species new to science. By the time the flora was finished, a total of 74 new species had been found within the region, and a total of 2104 species had been described! 

I met and corresponded directly with many of the 70 specialists who contributed to the text, but relied on Scott and his wife, Carol, to select material for me to work from. Since there was no clear deadline I was able to intersperse the project with many other jobs, switching back and forth whenever enthusiasm for one job or another flagged. 

Sitting in my studio drawing from herbarium specimens has always suited my demeanor, but as soon as I began Scott’s flora I realized I wanted to see the plants alive. I traveled twice to French Guiana with Scott and several of his collaborators, including specialists on orchids, bromeliads, and lianas. Both trips were approximately 2½ weeks long, with accommodations in a tiny remote village. We slept in hammocks in open-air shelters, one year in a French research station, the second time with a family who had created a comfortable ‘resort’ for scientists and eco-tourists. Long days were spent hiking trails in the rain forest searching for plants. Scott climbed trees in search of flowers, Carol took photographs while others pressed the collections, and I was tossed an endless stream of branches and flowers and fruits to draw. 

While I have always appreciated the challenge of drawing from herbarium specimens, I was absolutely enthralled with the opportunity to examine and sketch plants in the field. My personal notes describe the persistent biting insects and the heat and humidity, but I instead recall the extreme thrill and deep satisfaction of sitting in my little folding chair sketching intently. Being able to see the 3-D 

aspects, and the texture and color patterns certainly improved my illustrations. But beyond that, I was able to understand and appreciate the magnitude of Scott’s determination to document the flora of the lowland tropical forest. And I was able to prolong my own dedication to the long-term project. 

Using pencil in an 11x17” sketchbook, I worked as quickly as I could to document fleeting aspects of the plants, often concentrating on leaf arrangement or overall gestalt of the plant that would be lost when reduced to an herbarium specimen. Measurements were critical so I relied on dividers to block things out accurately, and made simple dissections with a razor blade while flowers and fruits were fresh. Often I had time for only a small critical detail before the next plant was handed to me, each more exciting than the last. Sketches were referenced to correspond to Scott’s collections. We pickled flowers in alcohol for future examination in my studio with my microscope. I sketched bits and pieces of 150 species, and then relied on the sketches over many years. As much as nine years went by from one sketch to finished illustration, yet the actual plant was still vividly clear in my mind because I had been so thoroughly involved when I drew it in the forest. In the intervening years of drawing most species from herbarium specimens, I was instantly re-invigorated every time I had to draw a plant I had seen in the forest. 

Back in the comfort of my studio, I use a consistent format for my illustrations with a paper size equal to an herbarium specimen (11½ x 16”). My sketchbooks are the same size to allow for ease of design elements. I begin each illustration in my studio by roughing out a basic ‘habit’ from a herbarium specimen (entire plant whenever possible, but more often a branch of a tropical tree). It is essential to accurately depict leafshapes and proportions and often necessary to show upper and lower surfaces of leaves to allow for species identification, so I arrange elements within my sketch to accommodate as many features as possible. Large tropical leaves and convoluted vines provide interesting design challenges. I use additional specimens to provide information for adding or repairing broken leaves or missing features. Photographs and written descriptions aid my reconstruction efforts, as do any illustrations of related species. And, as an avid gardener, I rely on my knowledge of temperate plants to provide inspiration. I live in Vermont, which is a long ways from the tropics, but I am always willing to dissect a sea holly or a cucumber blossom in my garden, or a jasmine amongst my houseplants, when I am asked to draw a related species from the tropics. 

Once the habit of a species is laid out on my plate, I determine how much additional detail needs to be included, based on a combination of instructions from the botanist, my own understanding of the species, and my artistic intent. And this again is influenced by the amount and condition of available material. Often I have pickled material that can be dissected and examined under the microscope. If I have no pickled material, I can re-hydrate flowers for dissection by soaking or gently boiling them. My dissecting scope has a long boom arm that allows me to position herbarium specimens under it for drawing details such as pubescence and glands. Microscope sketches are drawn at a scale appropriate to their complexity and importance, which might be a fruit enlarged to 2X, anthers at 10X and multicellular hairs at 40X. My eyepiece has a micrometer for accurate measurements. I rely on a nylon Schaedler graphic design ruler with ½ millimeter increments, and proportional dividers, my constant aid in both field and studio. 

Using the habit as the major element, floral and fruit details are laid out on my sketch in an order with each detail near to its counterpart within the habit, in an order around the plate, from vegetative parts through flowers to fruit and seed, which corresponds to a standard botanical description. I transfer the sketch onto Strathmore 500 series plate Bristol board, using a lightbox, and re-check the details under my microscope as I refine my pencil sketch. On rare occasions I fax a copy of the sketch to the botanist for review, but usually I begin inking the drawing while the specimens and dissections are right at hand. I use a Hunt 102 crowquill nib and Pelikan ‘Tusche’ ink. Corrections are made with an electric eraser. Scales and labels are added with a Leroy lettering set (an archaic but simple template system for hand lettering directly on the plate). Scott and the specialists approved each illustration as it was completed, and again as the manuscript went through a lengthy editorial and review process. We worked first with the monocots (including grasses and orchids), which were published as Volume 1 in 1997. I finished the final illustrations in August 1998. Volume 2 was published in December 2002 by The NYBG Press as part of the Memoirs of the New York Botanical Garden. The two volumes include 900 of Carol’s spectacular full color photographs and 401 of my line drawings. 

With a limited press run and an admittedly specialized and restricted audience, not many will see the results of our many years of labor. But, fortunately, Scott helped develop a new project, with the idea of treating the 280 known families of plants found in the new world tropics (the “neotropics”, between Tropics of Capricorn and Cancer). He and several co-editors solicited treatments from specialists all over the world, and asked me for illustrations available from any of my published work. I keep photocopies of my illustrations arranged by family, with related genera from various floras and monographs interfiled in looseleaf binders. The editors and I made selections of one illustration per family, and I was able to provide existing illustrations for 186 families. Funds were available from the publisher for an additional 28 plates and I was asked to choose which families I would like to illustrate, based on importance and availability of herbarium material. My first choices took me straight to my garden to compare species from familiar families - hydrangea, barberry, Saxifrage. I was even able to grow one tropical species on the list, Cobaea (cathedral bells), as an annual vine. Later choices were based on availability of herbarium material and importance to the flora. The final collection of illustrations ranged from a couple I had drawn over 20 years ago to ones I had barely finished for the text I was currently working on, Vines of Puerto Rico. Many of my existing illustrations were converted to digital format and could be given directly to the publisher, others were pulled from NYBG archives and copied or given as originals. The publisher, Princeton University Press, designed a page layout that reproduced the illustrations at 1/3 their original size. I was initially concerned about loss of detail but found that the images held up well, and even looked quite elegant at their small size. The publication, Flowering Plants of the Neotropics, appeared in February 2004 and is destined to appeal to students of botany throughout the world. 

  • Pothomorphe peltata, © Bobbi Angell
  • Symphonia globulifera, © Bobbi Angell