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HUNTIA a Journal of Botanical History HUNTIA A Journal of Botanical History Volume 11 Number 2 2002 Hunt Institute for Botanical Documentation Carnegie Mellon University Pittsburgh Huntia publishes articles on all aspects of the history of botany and is published irregularly in one or more numbers per volume of approximately 200 pages by the Hunt Institute for Botanical Documentation, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213-3890. Editor Scarlett T. Townsend Book Reviews and Announcements Editor Charlotte A. Tancin Associate Editors Gavin D. R. Bridson T. D. Jacobsen Angela L. Todd Frederick H. Utech James J. White Designer Lugene B. Bruno External contributions to Huntia are welcome. Please request our “Guidelines for Contributors” before submitting manuscripts for consideration. Editorial correspondence should be directed to the Editor. Books for announcement or review should be sent to the Book Reviews and Announcements Editor. We have eliminated page charges. Hunt Institute Associates receive Huntia as a benefit of membership; please contact the Institute for more information. Subscription rate is $60.00 per volume. Orders for subscriptions and back issues should be sent to the Institute. Printed and bound by Allen Press, Inc., Lawrence, Kansas. Copyright © 2002 by the Hunt Institute for Botanical Documentation All Rights Reserved ISSN 0073-4071 Huntia 11(2) 2002 Sebastian Vaillant’s 1717 lecture on the structure and function of flowers Paul Bernasconi and Lincoln Taiz, transl. Abstract The impact of the 18th-century French botanist 1993, p. 28). among those seated in the audience Sebastian Vaillant on plant systematics in general, and were about 200 medical students from the on Linnaeus in particular, has been underappreciated university. The opportunity to give the opening by students of the history of botany because his most remarkable piece of writing, a lecture given at the Royal lecture had arisen when the regular professor Garden in 1717, has never been translated into English. for the course, antoine de Jussieu (1686–1758) The topic of the lecture was the sexual function of (Fig. 1), who was also director of the Royal flowers and the importance of the floral organs in plant Garden and Vaillant’s boss, had asked Vaillant, identification. Because of its suggestive and flamboyant style, the lecture brought Vaillant considerable notoriety who was seventeen years his senior and whose and helped gain acceptance for the sexual theory of plant primary job was to maintain the herbarium and reproduction. In this translation, we try to capture some serve as “assistant Demonstrator,” to lecture in of Vaillant’s flair for colorful language that was to make his place while he traveled in Spain. To the an indelible impression on the young Linnaeus and exert such a strong influence on the sexual system of largely self-taught Vaillant, the son of a poor classification that he eventually devised. farmer and former army surgeon (Stafleu and Cowan 1986) who lacked de Jussieu’s academic credentials and family connections, it was a Introduction splendid opportunity, and he intended to make On the morning of 10 June 1717, Sebastian the most of it (Westfall [ca.1994]). Vaillant (1669–1722) strode into the large Despite Vaillant’s lack of university training, auditorium at the Royal Garden of Paris at he was well qualified to deliver the address, 6:00 a.m. confident that his lecture opening having studied for many years under the great the annual course on botany would be a zinger. Tournefort (Westfall [ca.1994]). Joseph Pitton The occasion coincided with the opening of the de Tournefort (1656–1708) (Fig. 2) had been a Royal Garden at a new location on the banks of professor of botany at the Royal Garden from the Seine, and the large hall was filled with about 1688 until his untimely death in 1708 when 600 people from all ranks of society (Schiebinger he was accidentally crushed against a wall by a passing carriage. In fact, Vaillant had been next in line to be appointed professor at the Royal Syngenta Biotechnology, Inc. P.O.B. 12257, Garden, but he graciously deferred to a close 3054 Cornwallis Rd., Research Triangle Park, friend, Antoine-Tristan Dainty D’Isnard (1663– nC 27709-2257 u.S.a. [PB] 1743). Due to illness, D’Isnard relinquished Department of Molecular, Cellular, and the post in 1709 after only a single year. This Developmental Biology, Sinsheimer Laboratories, time Vaillant was bypassed for the job, and the university of California, Santa Cruz, Ca 95064 ambitious young de Jussieu took over as professor u.S.a. Email: [email protected] [LT] when he was only 24 years old (Tjaden 1976). 97 98 Huntia 11(2) 2002 through Tournefort’s generous support that he had originally obtained his position at the Royal Garden. as it turned out, Vaillant died before completing this work, which was published posthumously by his good friend and mentor, Herman Boerhaave (1668–1738), Chair of Medicine and Botany, university of Leiden. For his lecture topic that morning, Vaillant had chosen a subject he knew would be well received by the adolescent male students sitting in the audience: the sexual function of flowers. By 1717, the idea that plants reproduced sexually and that flowers contained the sexual organs of plants, although still being debated, was no longer new. The British physician nehemiah Grew (1641–1712) had been the first to publicly suggest the notion in 1684, and the noted botanist John Ray (1627–1705) had immediately embraced it. The discovery of hermaphrodism in snails by J. J. Harder (1656–1711) in 1682 had allowed Grew to make the case for hermaphrodism in flowers by analogy. Ray supported Grew’s sexual hypothesis in his Historia Plantarum (1686) by Figure 1. Antoine de Jussieu, top portion of the engraving citing numerous examples of dioecious plants, by W. Evans after a painting by Thévenin. Plate for R. J. Thornton’s New Illustration of the Sexual System of Carolus such as date palms and spinach, in which the von Linnaeus …, 1807, pt. 2, [pl. 2]. Courtesy of Hunt male and female flowers reside on different Institute for Botanical Documentation. plants. Then, in 1694, the German physician Tournefort’s major contribution to botany Rudolph Camerarius (1665–1721) provided had been the concept of genus. In his Institutiones the first clear experimental evidence in support Rei Herbarai (1700) he had defined 22 classes of of the sexual theory. Working with dioecious flowering plants based primarily on the structure and monoecious (i.e., plants with male and of the corolla and 698 genera using the fruit as female flowers on the same individual) species the main taxonomic criterion. Other parts of exclusively, he showed that when the female the flower and vegetative body were given much flowers were isolated from the “dust” of their less weight in Tournefort’s classification scheme. male counterparts, they either failed to develop at the time of his opening lecture at the Royal seeds or produced infertile seeds. His results Garden, Vaillant was preparing his own magnum were published in the form of a letter to a opus, the Botanicon Parisiense, in which he planned colleague, titled De Sexu Plantarum Epistola, by to introduce a new system of plant classification, the Tübingen academy. unfortunately, news a forerunner of the Linnaean sexual system, of Camerarius’s experimental demonstration that was strongly at odds with those of his great of plant sexuality was slow to diffuse to the master and benefactor. His acerbic critique of outside world because of the journal’s very his former mentor’s classification system placed limited circulation. By the early 1700s, however, Vaillant in an awkward position, since it was the sexual theory was accepted widely by the Bernasconi & Taiz: Sebastian Vaillant’s 1717 lecture 99 best-informed botanists of the time, even those who were unaware of Camerarius’s work, with the exception of a few notable holdouts. To his dying day, Tournefort rejected the sexual theory of flowers and considered pollen to be merely a waste product, probably in deference to the opinion of his own mentor, the renowned Marcello Malpighi (1628–1694).1 To the general population, unaware of the recent developments in botany, the idea of sexuality in plants would have been a shocking and somewhat disturbing revelation. as pointed out by Rousseau (1970), society in early-18th- century France was quite puritanical and marked by an emphasis on good manners and refinement among the higher social classes. Publicly referring to sexual organs by name, and expounding on their functions, was simply not done in polite company. applying sexuality to plants, unless it was couched in the driest possible terms, would have bordered on the indecent, all the more so since most flowers are hermaphroditic, a difficult concept for the contemporary layperson to grasp and accept. But Vaillant had entered the arena of polite society through the back door and seemed to relish his role as iconoclast. Besides, he Figure 2. Joseph Pitton de Tournefort, engraving by J. Hopwood. Plate for R. J. Thornton’s New Illustration of the knew that the students in the audience, chafing Sexual System of Carolus von Linnaeus …, 1807. Courtesy of at the strictures imposed by their elders, would Hunt Institute for Botanical Documentation. respond enthusiastically to anything with radical content, especially concerning the taboo subject The pride of place given the sexual organs in of sex. What he did not know, however, was Linnaeus’ classification system was anticipated in that the student who was to get the most out of his university thesis, titled Praeludia Sponsaliorum his lecture was not even in the audience on that Plantarum, written in 1729. In this thesis Monday morning in Paris. He was living in the Linnaeus waxed poetic on the theme of plant isolated village of South Råshult in Sweden, an “nuptials” and did not shrink from using a term imaginative and romantically inclined ten-year- — genitalia — normally reserved for the sexual old boy named Carl von Linné (1707–1778) (Fig.
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