G.M. Darrow, The Strawberry: History, Breeding and Physiology
ON JULY 6, 1764, Antoine Nicolas Duchesne (Fig. 5-1) personally presented King Louis XV with a pot of strawberries. The fruits were specimens of the Chilean berry (Fragaria chiloensis) and had extraordinary size and beauty. Fruiting F. chiloensis was a rare sight since the plants were female, but the seventeen-year-old boy had used pollen of the musky strawberry (F. moschata) with spectacular results. On the advice of his head botanist, Bernard de Jussieu, the king honored Duchesne by ordering Mademoiselle Basseporte, the famous botanical artist, to paint the berries for the collection in the Royal Botanic Library. In addition, he authorized Duchesne to raise more F. chiloensis in the royal kitchen garden at Versailles and to collect all varieties of strawberries known in Europe for the Trianon garden.
Two years later, research and experiments produced the most scholarly, complete treatise ever written on the natural history of the strawberry. For a nineteen-year-old boy it was a remarkable achievement, but it was more remarkable still as an illustration of the cooperation and enthusiastic involvement of eighteenth-century scientists, farmers, and home-gardeners in attempts to exploit the variation of nature. Duchesne wrote to all of them for his collection. He wanted their plants and their descriptions of the behavior of wild and cultivated strawberries in their regions. He pressed them to speculate with him about the directions nature had taken in the past and why. They did their best to answer him, from their chairs in the great universities, from the rounds of a village priest, from gardens in the countryside of England, France, Switzerland, Germany, and Sweden, and from the Office of Naval Defense in Brittany. Their lives and attitudes were not comparable in many respects, and when Duchesne asked them to consider the strawberry he found the same diversity in their experiences with it. Yet their replies to his questions were the materials for his balanced and reasoned discussion of strawberry evolution. The conclusions he derived generally remain valid today.
The discovery that strawberry plants could be unisexual as well as bisexual set Duchesne off on his study of natural history. He first found unisexual plants in the musky-flavored strawberry, F. moschata (Fig. 5-2), and then noticed the same condition in the foreign strawberry from Chile, F. chiloensis. There were no male Chilean strawberries in Europe, but with male moschata (Fig. 5-3) planted nearby, female F. chiloensis would produce the enormous fruit for which it was famous.
Fragaria chiloensis had not flowered in Duchesne's garden in the spring of 1764 so he and his father had asked M. Richard, the king's botanist-gardener at the Trianon, the Royal garden at Versailles, to send them some F. chiloensis to study. On the 29th of May Richard sent a single potted plant with one stem and two branches, which were divided into eight pedicels. In all there were eight buds, two of which were long past blooming and one which already had withered. No berries had formed. Duchesne recognized at once that the flowers were female and despaired of obtaining any fruit as he knew of no male F. chiloensis. The plant did resemble F. moschata and so he placed it in his collection of strawberries, next to male F. moschata. Hardly had the petals of one flower fallen when on June 6th he saw its receptacle beginning to enlarge, the first stage in the formation of a berry. A little later he was certain that the fruit had set. "I did not doubt for an instant that the neighboring F. moschata had fertilized it," wrote Duchesne (Fig. 5-4).1The next three fruits also set. Duchesne removed the last two flowers so the plant could concentrate its strength and develop bigger berries from the flowers already fertilized. The first of the berries, which was very large, ripened during the first days of July and the others soon followed.
How did such experiments in natural history come to capture the Duchesne boy's attention in the first place? He was born October 7, 1747, at Versailles, where his father, an architect and painter, had inherited the post of superintendent of the king's buildings, an office created for his father by Louis XIV. Left motherless at birth, the boy received the devoted attention of his scholarly father, a man learned in Greek, Latin, and several modern languages, a lover of the fine arts and the natural sciences. All his knowledge was concentrated on his son's education. As a four-year-old the child could read, knew four hundred Latin words, and could recite numerous historical anecdotes which his father had taught him in discussions or in the instructive games he invented. His father kept him occupied constantly, varying his studies to maintain interest. As soon as the boy was old enough the two began a series of walking tours which took them around Versailles and Paris to public and industrial establishments; later they walked to Fontainbleau, Campiegne, Le Havre, and Reims, where the boy watched the coronation of Louis XV. M. Duchesne insisted that his son miss nothing, and urged him to puzzle over all he saw. He made a small notebook for him in which to describe their observations of each excursion. Soon the boy was recording his own observations from these walks (his father insisted they travel everywhere on foot). Meanwhile, lessons progressed in Greek, Latin, English, and Italian, and in history, geography, mathematics, drawing, and music. The zealous teacher made every childhood amusement and game a physical or moral means of instruction.
Natural history was the boy's favorite subject. In his free moments he would visit the Trianon Garden, which his father supervised as superintendent of the king's buildings. The collection of the botanic garden fascinated him. But more engaging than the garden itself was the kindly royal botanist, Bernard de Jussieu, who allowed the boy to follow him about the countryside in his gardening work. The shy, solitary scientist began to instruct his small companion in the botanical characteristics and methods of classification of the plants they handled. He taught him how to make plants reproduce and what to do with the seeds, bulbs, and runners. He pointed out strange features, like the separation of sexes on some plants, and insisted on precise notation of the particular seasons for transplanting, fertilizing, pruning, and the effects of temperature changes.
Good fortune had brought Antoine Nicolas Duchesne the finest teacher of natural history in all of Europe. Bernard was second in the five-member de Jussieu dynasty of botanists who occupied for nearly a century and a half a pre-eminent place in botanical science. Bernard's older brother, Antoine, to whom Frezier had sent an F. chiloensis plant, was "Professor and Demonstrator of the Interior and Exterior of Plants" at the King's Garden (a post formerly held by Tournefort). He was also a prosperous doctor with a large clientelle. In 1714 he brought his fifteen-year-old brother Bernard to Paris where he became "Assistant Demonstrator of the Exterior of Plants at the King's Garden." Bernard's job entailed the organization and inspection of all open-air and hot-house cultivation, the instruction of the gardeners in his charge, and the leading of botanical excursions into the countryside around Paris. Bernard also prepared all the courses taught by his older brother, the busy doctor. Bernard kept house, receiving their few but select friends: famous botanists like Le Monnier, Duhamel du Monceau, Malesherbes, and Poivre -- along with foreign visitors passing through Paris. Their house became known as a salon dedicated to scientific discussion. Among the visitors from abroad was young Carl Linnaeus, who stayed with the de Jussieu brothers for a month following his departure in 1738 from Hartecamp where he had served as George Clifford's gardener and doctor.... A strong admiration and warm friendship united the two greatest botanists of the age and for thirty years Bernard and Linnaeus exchanged letters, living and dried plants, and seeds. Their correspondence included criticism of recent publications, comments on the activities of the French Royal Academy of Sciences (both were members), and discussions of scientific expeditions, particularly those of friends and students. Anything new in the world of science interested them -- zoology, biology, and medicine, as well as botany.
Through interest in Linnaeus' sexual system of classification and his method of binomial nomenclature, Bernard de Jussieu had developed ideas of his own on a natural method of plant classification. The earlier botanists like Ray, Morison, Magnol, Vaillant, and finally Linnaeus himself, had foreseen such a relationship but had formulated no rules or descriptions. Bernard's interest had centered on this by 1759, when King Louis XV, an enthusiast for all the sciences but especially botany, requested him to collect all the plants cultivated in France in the Trianon Garden and to establish a school of botany there. For several years the king personally followed its development and encouraged de Jussieu with kindness and friendship.
Modest and hesitant, Bernard wrote only three small essays on botany in his whole life. He published nothing on his natural method of classification and left behind no record of the directing principles behind his research. He used his system in only one work, the catalogue of the plants in the Trianon collection, but this remained in manuscript form as a list of names which he revised continually right up to the last hour before his death. Bernard had refused the vacant professorship left by his brother, who died in 1758, and so he remained an under-demonstrator, passing most of the day in armchair meditation across the room from his studious young nephew. The two men broke their rigorously imposed silence only in the evening when Antoine Laurent de Jussieu read to his uncle, awaiting his comments and ideas.
By the time the seventeen-year-old Duchesne began his study of strawberries he already had published Le Manuel de Botanique. This manual described the characters and properties of plants cultivated around Paris and their nutritional, medical, artistic, and ornamental uses. With Bernard's approval, Duchesne had given common names to all these plants, carefully substituting new names for inaccurate or confusing older ones. The praise scientists gave the book encouraged him to continue his observations. With Louis XV's authorization to extend the collection of strawberries in the Trianon Gardens -- the reward Duchesne received for his unusual strawberries and his eagerness to learn more about them -- Duchesne wrote to botanists and gardeners all over Europe. Frezier, then in Brest, was asked for a detailed account of his collections of the Frutillar, fifty-one years earlier in Chile. The village curate from the Montreuil area was pressed into service. Could he discover the origin of the common market-garden variety of F. vesca, a large-fruited wood strawberry called the Montreuil strawberry? Von Haller in Switzerland was asked to send native species. A bishop from Bargemon, a town in the Alps du Var, searched the countryside at Duchesne's request to test the ancient report of a twice-bearing strawberry which grew in the neighboring mountains.
In his enthusiasm, Duchesne did not hesitate to approach the great Linnaeus himself, the old friend of his tutor, Bernard de Jussieu. The distinguished botanist proved most approachable and for ten years he corresponded with Duchesne, exchanging several species of plants and tolerating (though not accepting) the audacious youth's criticism of Linnaeus' own classification of strawberries. Linnaeus fully approved Duchesne's initiation of a depth study in botany, a most unusual attempt in an age devoted to classification and systemization. "When you have completed the history of the wild strawberries, you will have accomplished something which I long have hoped that some botanists would do; namely, that they would each choose their plant family and examine it most thoroughly; in this manner would soon be attained the ultimate knowledge of plants which now floods botanists with its abundance," he wrote Duchesne from Hammarby on September 24, 1765.2
Duchesne did study his plant family, the Fragaria, thoroughly. His book, which details this study under the title of L'Histoire Naturelle des Fraisiers, begins with a description of the genus as a whole, and then follows with an examination of each of the ten species and eight varieties with which Duchesne was acquainted. He intended to accompany each with a drawing of the plant as he had seen it growing at Versailles, but he lacked the money to do so. Several of these drawings, so realistic that botanists have since said they could survive microscopic inspection, were discovered by this author in the Paris Museum de l'Histoire Naturelle and are published here for the first time. Yet Duchesne's botanical descriptions could not have been more exacting and precise. For each strawberry he tried to trace the history of its European introduction, cultivation, and distribution from the earliest botanical references in medical books and garden catalogues on up to the year that his book was published. He included notations of flowering and fruiting seasons and weather effects for each species. In a truly unusual attempt for his century, he pointed out what he thought to be the oldest and the newest species and then offered his reasons which were based on the differences among the species and their distribution. He went on to suggest which kinds might have descended from which. The order in which he discussed each species followed this system and the author summed up his ideas in the drawing of a genealogical tree.
He devoted the second part of his book to strawberry culture. Here he evaluated the different methods of fertilization, propagation, and the forcing and retarding of the fruiting time of different kinds. The final section of the book, entitled Remarques Particulieres, he divided into four detailed little essays on puzzling aspects of the natural history of plants ,which his study of Fragaria had suggested.
The ten species (or "races" as Duchesne called them) in the order in which he described them were:
I. The Alpine or Fraisier des Mois (F. vesca semperflorens)
II. The wood strawberry or Fraisier de Bois (F. vesca silvestris) and its six "varieties"
a) the variegated (F. vesca variegate)
b) the white (F. vesca alba)
c) the double (F. silvestris multiplex)
d) the clustered (F. silvestris botryformis)
e) the Plymouth (F. silvestris muricata)
f) the coucou (F. silvestris abortiva)
III. The Fressant or Montreuil strawberry (F. hortensis), a cultivated garden variety of the wood strawberry with fruits which Duchesne said were fifteen to twenty times larger than the common Paris market variety of his day.
a) le blanc fraisier de fressant, a white variety of the above
IV. The runnerless wood strawberry (F. efflagelis).
V. The Versailles strawberry (F. monophylla), a wood strawberry with simple leaves.
VI. The green strawberry (F. viridis)
VII. The musky or Hautboy or Capiton strawberry (F. moschata)
VIII. The Chilean or Frutillar (F. chiloensis)
IX. The pineapple or ananas strawberry (F. ananassa)
a) The "fraisier pannache," a striped-leaved ananassa
X. The scarlet or Virginian (F. virginiana)
Several discoveries important to the new science of plant breeding emerged from Duchesne's study, and he showed their practicality by applying them to the cultivation of strawberries. He was the first to recognize the separation of sexes in strawberries. Though rarely cultivated today, F. moschata, the musky-flavored strawberry, was common in eighteenth century gardens, as its fruits were considerably larger than those of the wood strawberry. It was a difficult berry to raise, however, since after a few years in a garden half of the F. moschata plants would be found sterile and had to be pulled out. Soon the remaining plants would bear less and less and the gardener would have to search again for new vigorous plants. By studying F. moschata, Duchesne discovered that the sexes were separated in this particular species. Unless some of the "sterile" plants were allowed to grow near the "fertile" fruit-bearing females, not a single berry could be expected in the whole bed of musky strawberries. Duchesne's teacher, Bernard de Jussieu, had pointed out cases of separate sexes in other plants, among them a peach tree which bore only male flowers and thus no fruit. Linnaeus had described the Latoch raspberry from Lapland in 1753 which had unisexual plants, the female flowers bearing only rudimentary stamens. The gardener of a friend of the Duchesnes, to whom they had given an F. moschata plant in 1760, had tried tearing out all F. moschata from the garden except one fertile plant. He propagated this plant from runners until he had filled a bed twelve to fifteen feet long with its offspring. The following year he could not find a single edible berry. "Then regretting the sterile plants which he had so carefully destroyed, he told me that doubtless they were necessary to fertilize the others," said Duchesne.3 The gardener recalled that the stamens on sterile F. moschata were very hardy, but he had not suspected that the fertile individuals were absolutely barren of pollen.
To the young gardener's observation, Duchesne owed his first suspicion of the unisexual character of the female musky strawberry, F. moschata.
Duchesne began experimenting on F. moschata in the summer of 1765. He took a female, or fertile, plant from a garden where it was growing among males and set it in a pot. Eight of the flowers were in the process of developing into fruits, five or six were withered, and about twenty were still buds. Duchesne cut off those flowers which might have been already fertilized and five of the developing fruits. He marked the three remaining infant fruits with thread and placed the pot in isolation on the windowsill of his room. All the later flowers which opened there withered, but the three infant fruits that he had marked developed into mature fruit. This experiment convinced him that a fertile female plant, already bearing young berries, would form no additional berries when isolated from male plants of its species.
Duchesne next asked himself if F. moschata could be fertilized by pollen from other kinds of strawberries. He placed another pot containing a female plant on his windowsill and surrounded it with four F. vesca plants and F. virginiana. No fruits formed despite the presence of the other species About that time, while walking around Montlhery, he saw some strawberries in the garden of the Lord of Villebousin and observed that there were two female F. moschata growing in a bed of Fressant (F. vesca) strawberries. A he suspected, they were unfertile through the lack of male F. moschata plants. "These last two observations," wrote Duchesne, "while confirming that the female Capitons (F. moschata) cannot fertilize themselves, seem to indicate in addition that common strawberries (F. vesca) are incapable of fertilizing them."4 Independent of these experiments, close examination of the female flowers themselves showed Duchesne that they needed males as pollinators since the undeveloped stamens were totally lacking in pollen. He also note a secondary sex characteristic -- male F. moschata flowers were larger than those of the females.
In great excitement Duchesne wrote to Linnaeus describing his discovery. He received a stern injunction to examine his F. moschata "males" more closely. Linnaeus suspected them to be frost-bitten hermaphrodites (bisexual plants) which he said were easily mistaken for males. "While you are talking about sex, I ask that you take care lest you are considering flowers consumed by a spring frost as masculine, which happens frequently in our country. I have never seen or observed masculine flowers in any strawberry," concluded Linnaeus in a letter of September 24, 1765. 5
"No one, I believe, suspected before me the separation of the sexes in the Capiton," Duchesne stated in his book. 6
Neither was Linnaeus of much help in answering Duchesne's other question about F. moschata. "Did it grow wild in Sweden?" Duchesne had asked, trying to trace the original source of the plant. Linnaeus, however, had confused F. viridis with F. moschata and thus could not give Duchesne a convincing answer. Linnaeus reported that the green strawberry "is very common here and completely spontaneous; it grows on all slopes but especially by roadsides and on the sides of larger ditches, while vulgaris (that is, the wood strawberry) occurs in open woods, clearings, and burnt woodlands, where the green strawberry is never seen. I cannot distinguish the green strawberry from the usual wood strawberry through the plant itself, but only by the fruit, so similar are the two."7
In identifying the green strawberry, Linnaeus had cited Bauhin's Fragaria fructu parvi pruni magnitudine, the strawberry with fruit as large as a small plum, as his source. Duchesne believed this was F. moschata, the musky-flavored strawberry, and not the green strawberry as Linnaeus claimed. The origin of F. moschata was unknown. Rumors had described it as American or oriental. It was cultivated in France, England, Sweden and Germany, but certainly it was not native to France. Yet Linnaeus described it as "completely spontaneous" in Sweden.
In a discussion of the cultivated Swedish garden strawberry, which he called F. hortensis, Linnaeus said that this strawberry, was grown both in French and Swedish kitchen gardens and that it differed from the wood strawberry and the green strawberry of Sweden only by the size of its fruits, since the fruits of the wood and green berries were the same size. He then said he thought the cultivated garden strawberry (which was really F. moschata) must be the green strawberry and he planned to plant a green strawberry from the wilds in his garden the next year to see if it would grow berries as large as the garden strawberry.
How could one of the greatest botanists of the day confuse two so different species as F. moschata (his garden strawberry) and F. viridis (his green strawberry)? As Linnaeus himself said, "the green strawberry is bleak in color compared to the wood strawberry, less perfumed, and comes off the plant with the calyx attached." The only obvious explanation for his confusion is the use of the common name "strawberries" in Sweden for both F. moschata and F. viridis, the green or wild hill strawberry, of Sweden. Duchesne could never be sure that the green strawberry was the true wild F. moschata (Fig. 5-5).
The discovery of separation of sexes in the musky strawberry alerted Duchesne to the same possibility in other species and he easily recognized that the Chilean, too, was dioecious -- at least only females had ever been seen in Europe. Other botanists before Duchesne had attributed the Chilean's sterility to its impotent stamens which lacked pollen. Duchesne was the first to discover a successful pollinating agent for it, thus remedying its sterile condition. Other botanists had tried to pollinate it with F. vesca pollen but had failed. Noting its resemblance to F. moschata, Duchesne used the musky strawberry as a pollinator for the Chilean and produced the famous berries which he presented to Louis XV in 1764. Noting also that F. vesca pollen had failed to pollinate female F. moschata, Duchesne suggested that this mutual disinclination might differentiate them as species. With characteristic caution, he wrote: "Before concluding anything from these observations, it is doubtless necessary to repeat them (attempts to pollinate F. moschata with F. vesca), and it would be very useful if several persons should do so. But if the experiment confirmed this, it seems to me that one could hardly avoid regarding the common strawberry (F. vesca) and F. moschata as two species, despite their very intimate resemblance, just as one generally recognizes the dog, fox, and wolf as different species because they refuse to mate together."8
The Chilean strawberry had been grown successfully as a market variety in the Brest area of France for some years. What were the berries used as pollinators? Duchesne wondered. M. Duhamel, a famous botanist of this period, attested that in the better-tended plantings of F. chiloensis "half of the strawberries were of an entirely different sort, which has the regional name of Barbary strawberry."9 He sent some of these to Duchesne who found them to be an assortment of F. virginiana and F. moschata. None was F. vesca. The dioecism present in F. moschata and F. chiloensis and their ability to cross suggested a genealogical relationship between the two species to Duchesne.
He wondered if F. moschata was dioecious in its wild state. Taking Linnaeus' word that the green strawberry of Sweden (F. viridis, also called the meadow or wild hill strawberry) differed from the cultivated garden strawberry there (F. moschata) only in the size of its fruits. Duchesne surmised that the green strawberry must be F. moschata in its wild state. According to Linnaeus, this was a perfect hermaphrodite and so Duchesne described it as F. moschata before its degeneration into the unisexual condition always found in cultivated F. moschata. "The solidity of the fruit, the large stamens and the hairiness of the plant leads me to believe that F. moschata owes its origin to the green strawberry rather than to any other," he wrote.10 There was no wild F. moschata in France. Perhaps then, he reasoned, the adaptation to the climate change between France and Sweden was responsible for F. moschata's degeneration. Perhaps F. chiloensis cultivated in Chile was likewise bisexual and "perhaps the change in climate has caused the defect observed in ours (F. cholensis in France)," he said.11
In the Trianon Garden Duchesne had discovered a partially bisexual flower on one of the Chileans which had come from Cherbourg in 1764. In 1765 this particular plant had one flower that produced mature seeds while all the other flowers dried up and died. This one flower produced an imperfect fruit bearing fourteen ovaries or seeds, and consequently looked rather like a raspberry. Duchesne planted a few of its seeds which germinated successfully, proving to him that some of the stamens on the Cherbourg F. chiloensis must have been fertile. Thus he wrote: "Here is an example of an almost perfect hermaphrodite (bisexual plant) which supports the possibility of the preexistence of bisexual individuals which would have produced other unisexual or hermaphrodite-unisexual ones."12 Duchesne kept this individual along with two runner plants. He also kept the young Chileans derived from its seeds to compare with seedlings produced by the fertilization of Chilean flowers with the musky strawberry's pollen.
"To settle this question" of whether a change in climate made Chilean plants unisexual in France, he was careful to add that "it would be important to import fresh seeds of the Frutillar (Chilean) from Chile, or better yet, living plants. . . . While supposing, as seems reasonable to me, that the separation of the sexes or at least of their potency, is natural to this species (F. chiloensis) and to the Capiton (F. moschata) it is very probable that the first has originated from the second." And he added, tongue-in-cheek, "One cannot object that if there were males and females (of F. chiloensis) in Chile, people surely would have perceived them in cultivating them, since people in Europe are still unaware that the Capitons are not hermaphrodites."13 The hole in his genealogical theory, Duchesne admitted, was the lack of an explanation of the way F. moschata could have traveled to Chile to become F. chiloensis. Still, it is impossible to ignore Duchesne's observation in 1766 that F. moschata resembled F. chiloensis more closely than any other European strawberry. Genetics has since revealed that the somatic chromosome number of F. moschata is 42 while that of F. vesca is only 14.
Many questions arose in Duchesne's mind about cross-fertilization among strawberry species and the characters of the hybrids derived from them. He was certain that there were consistent laws permitting hybridization between certain kinds and preventing it between others. He wondered if the capacity for plants in a genus to hybridize with each other could be the guiding principle for distinguishing among species. Future observations, he believed, would answer four important questions: (1) Whether male Chileans existed and whether they could fertilize female F. moschata; (2) whether perfect flowers occur on female F. chiloensis plants, making them capable of self-fertilization. If so, this would suggest that there have been hermaphrodite F. chiloensis plants at other times, and that they might have desce nded from the hermaphrodite F. vesca. (3) Whether F. vesca is really incapable of fertilizing F. moschata and F. chiloensis. If F. vesca could not fertilize them it would invalidate the preceding theory, and consequently would prove F. vesca a distinct species. (4) Finally, "by examination of the Frutillar (Chilean) derived from seed fertilized by the Capiton (male musky) which I have sown, as have M. de Jussieu and M. Richard, and of which several have germinated already, one will see what changes foreign pollinations effect, and how the resemblance of children to their mothers and to their fathers is regulated in plants." Duchesne hoped that such observations truly would produce new insight on "that very agitated question: whether the crosses and hybrids in plants follow the same rules as in animals."14
The young author was able to observe several of the crosses between the Chilean and other species. As he had speculated, several of the progeny proved to be perfect hermaphrodites. These were F. ananassa, which through future breeding would give our modern, big-fruited strawberry, producing crops without dependence upon interplanting with other kinds for fertilization. Duchesne was the first man to identify the parentage of the new strawberry: "I suspect it to be a cross of the Scarlet strawberry (F. virginiana) and the Frutillar (Chilean)," he wrote in 1766.15 It was the resemblance of the new "pineapple" strawberry, or F. ananassa, to both F. virginiana and F. chiloensis which persuaded Duchesne that it must be an intermediate between them and he so placed it on his genealogical tree of Fragaria. Duchesne described its resemblance to F. chiloensis as that of a son to a mother, fertilized by a foreign father which he believed could only be F. virginiana (Fig. 5-6).
Duchesne's botanical description of F. ananassa, the hybrid, follows: The flower stems, branches, and pedicels of F. ananassa resemble those of F. virginiana though due to their vigor they are larger than those of F. virginiana by half (Fig. 5-7). The flowers almost equal F. chiloensis in size, but are more regular, with six petals and a similarly reflexed calyx. The fruit has no resemblance to F. virginiana but has a pale red color with a brown and yellowish cast, with very watery but solid flesh, like that of the musky strawberry and the Chilean. In its center is a rather large cavity within which is a large, long central core which adheres to the calyx when the fruit is picked. The ovaries are almost as large as those of the Chilean and are spread quite wide apart over the surface. The flesh swells very little in their interspaces, however, and thus is compact. The perfume of the fruit is closely similar to that of the pineapple. Pyramidal in shape, the berries are only a little smaller than the Chilean in size. The leaves are larger than those of the Virginian with petioles nearly twice the length so that each leaflet goes in a different direction, although on a horizontal plane. The leaflets are more vigorous and thicker than the Virginian's, so that they have a rough leathery texture like the Chilean's. They lack the dense pubescence of the Chilean, having very little hair. The plants resemble the Chilean in its vigor and its runners are about as big and as long. In color the leaves are like those of the Virginian.
F. ananassa (the resemblance of the new strawberry to the pineapple in odor, taste, and berry shape gave it this name) had been introduced only a few years before Duchesne wrote L'Histoire Naturelle des Fraisiers. Philip Miller first cited it in the 1759 edition of the Gardener's Dictionary and included an engraving of it in his book of illustrations of the plants described in his Dictionaries (Plate 5-1).
Although Miller had heard that it had originated in Louisiana or maybe Virginia, he finally decided it had come from Surinam, for so he was told by George Clifford, the Amsterdam banker-gardener who had sent Miller a specimen of F. ananassa (Plate 5-2)just as he had given him F. chiloensis thirty years before. Because of its resemblance to two or three other species of strawberry, Miller refused to take the responsibility for naming it as a distinct species or a new variety from seed. In the 1759 Gardener's Dictionary he identified it with F. virginiana as a single species and in the 1760 edition of engravings he labeled it the "Surinam Strawberry."
Duchesne saw his first F. ananassa in 1765. M. Richard, the botanist-gardener of the Trianon, had some F. ananassa plants which he had brought from England for the king, but which Duchesne thought looked different from the one in Miller's drawing. In an article published some years later in Lamarck's Encyclopedique Methodique Botanique, Duchesne discussed the wide variation common to hybrids of F. virginiana x F. chiloensis, some resembling one parent considerably more than they did the other.
When in 1764 F. ananassa was brought to Paris by two or three interested people, Duchesne was informed by M. Le Monnier, professor of the king's garden, that it came from the gardens in and around Aix-la-Chapelle (Aachen), Germany, near Rheims, where it had been cultivated for several years. Even before 1764, Daubenton had cultivated F. ananassa at Montbar in Burgundy. In the spring of 1762 Daubenton received three unlabeled plants from Baron de Worb, M. de Graffenried, of Switzerland, in a shipment of packaged trees. Baron de Worb grew several foreign strawberries in his garden, some from Canada and some from Virginia. Did the Baron receive this F. ananassa from another country or was it produced by an accidental cross of the Virginian and the Chilean in his own garden in Switzerland? When Sir Jansin saw a specimen of Daubenton's strawberry in the king's garden he recognized it as one the English had pointed out to him as the Double Scarlet, as if to connect it with the Scarlet strawberry (F. virginiana) and to note that it was double in size. Other Englishmen identified it for him as the Bath Strawberry, associating it with the name of the city where it was first cultivated in England.
In 1766, Duchesne also knew of a strawberry from Holland which the Dutch merchants advertised in their catalogues as the Strawberry from Chile with fruit in the shape of a pineapple, "but it is known how little one ought to agree with their nomenclature," cautioned Duchesne.16 He noted how much this Dutch berry resembled F. ananassa in the Trianon garden and suspected that the Dutch fruits would resemble the drawing of Miller's plant, since Miller had received it from Amsterdam. Duchesne knew also of a variety with leaves striped with irregular bands of whitish yellow which he called F. ananassa variegate. This had been brought to the Trianon Garden from Holland along with regular F. ananassa.
By 1771, when he published a supplement to his L'Histoire Naturelle des Fraisiers in Lamarck's encyclopedia, Duchesne knew several varieties of F. ananassa. These he now called Quoimios, a name he borrowed from the English Quoimio or Coamiau and which he applied to all the big-fruited New World strawberries and their crosses.
First he cited the Quoimios (pineapple strawberry) of Haarlem, Holland, from a cross whose fruit was the first to be called Fragaria ananassa in botanical literature. It resembled the Chilean in color and somewhat in the shape of its fruits, in its flesh, and in its very similar, though fainter, perfume, so fleeting that people ate the fruit while it was still green or downy. This variety was a perfect hermaphrodite and produced fruits when planted by itself. However, the topmost flowers of a cluster rarely developed fruits, and as this strawberry was late in flowering it was particularly suitable for pollinating the very late female Chilean. For this reason Duchesne thought these two ought to be planted in alternate rows. He believed that this Quoimio probably originated at Haarlem, Holland, and around 1762 spread to Germany, to Switzerland, and then to England.
A second F. ananassa variety he called the Quoimio de Bath (F. calyculata) (Fig. 5-8), a variety whose berries were often smaller than those of the Chilean, but whose plants surpassed all others in vigor and size. Its branches and runners, equal in size to those of the Chilean, were much less hairy and much more numerous. The leaves were much larger and the six-petaled flowers had remarkably large calyxes with sepals clothed on the underside with white hairs. In shape the fruit was round and a little conical and sometimes flat and palmate rather than angular. The flesh was very white and light, swelling a good deal between the ovaries (seeds). In color the berries were dull white if kept in the shade, but under the sun became a soft, even, flesh color. They had a delicate perfume. The Bath strawberry was a prolific producer and formed crowns which lasted two to three years. It required sandy soil. The English had also recently cited a strawberry very similar to the Bath but with larger fruits which they called the Devonshire strawberry.
The Carolina strawberry, a third F. ananassa variety (Fig. 5-9), resembled both F. virginiana and F. chiloensis and had the regular, five-petaled flowers of F. vesca, although much larger. Its fruit was invariably round in shape with a light flesh almost like that of the wood strawberry in substance. It was less juicy than other berries and had a peculiar perfume. Since it did not swell much between the seeds, and thus, Duchesne noted, retained more color, its appearance was almost a cherry red. This compactness permitted the berry, if not bruised, to keep its quality two or three days after picking. Its small leaves, like the stem, resembled those of F. vesca. Unfortunately, the Carolina was often sterile. Since this occurred only in old plantings, Duchesne thought it might be remedied by planting the seeds in nurseries with sandy soil. He gave nothing about its origin.
A fourth variety of F. ananassa was the Quoimio de Cantorberi (Fragaria tincta or F. Quoimio). This was the variety first called Quoimio or Coamiau in England. Duchesne knew nothing of its source. Very like the Carolina strawberry, its fruits were a little smaller and less regular, and they were not pointed at all. The fruit had a deeper color which penetrated well into the flesh so that the juice was red almost like that of the mulberry. The berries had a high, somewhat strong and wild perfume. All these characteristics made Duchesne suspect the Quoimio de Cantorberi to be a pure species from some area in North America, or at least a naturally occurring variety.
A fifth F. ananassa, the Clagny Quoimio (F. hybrida, le Fraisier de Murmarais) Duchesne thought a hybrid variety probably derived from the backcross F. virginiana x the Quoimio de Haarlem (F. ananassa). It resembled the Virginian in the arrangement of its flowers, the substance of its fruits, and in its scarlet color. Although it bloomed the earliest of all strawberries, it gave a small yield. Duchesne first saw its fruits produced in 1770 near Versailles, in a garden called Murmarais, across from Clagny.
Why Holland is given exclusive credit for the introduction of F. ananassa (the Quoimio de Haarlem) is an unanswered question, especially since it would seem that the Brest F. chiloensis, fertilized by F. moschata and F. virginiana, must have produced some F. ananassa seedlings almost at once, which then most likely spread to other areas of France. Duchesne had been told that F. ananassa brought to Paris in 1764 came from Aix-la-Chapelle. Perhaps Holland is credited because Philip Miller received his first F. ananassa from George Clifford of Amsterdam, or because some of the early F. ananassa in the French botanical collection at the Trianon Garden and in the king's garden at Paris had been brought from Holland.
The Dutch might have made the acquaintance of F. ananassa in two ways. First, the plant might have been sent from Brest, as the Dutch seed merchants presumably imported new plants as well as exported them. lf these merchants had requested seed from Brest, they would have received seed from either F. chiloensis x F. moschata or F. chiloensis x F. virginiana and Duchesne describes Dutch F. ananassa as intermediate between the latter two.
A second possibility is the cross of F. virginiana x F. chiloensis within Holland itself. Six years after Frezier's return from Chile, F. chiloensis from the Leyden botanical garden in Holland was noted in Boerhaave's botanical work of 1720. Antoine de Jussieu had sent to Leyden a runner plant of the female Chilean given him by Frezier. Assuming that the Dutch were then cultivating F. virginiana, as there is every reason to believe those marvelous gardeners did, circumstances favored natural hybridization of the two species. That this hybridization occurred accidentally seems most likely, since the Dutch merchants first called F. ananassa, F. chiloensis ananaeformis (F.chiloensis with the shape of a pineapple) in their catalogues.
Perhaps the most exciting ideas in Duchesne's depth study of Fragaria come from questions raised in his mind about the natural history of plants, for his acumen was such that he constantly sought relationships between strawberry varieties, and patterns of change and development in living things. Duchesne's first letter to Linnaeus, dated Versailles, December 10, 1764, concerned his discovery of monophyllous F. vesca:
"In the garden of my most adored father, there has originated an offspring from seeds of Fragaria vesca, which alone does not have ternate leaves but instead simple leaves. It has grown here for three years and exhibits, as it creeps with its innumerable runners, a descendant which does not differ from the mother plant. In the past months of May and June it has given flowers and ripe berries with a most delicious taste and a shiny, scarlet red color, and rich with fertile seeds. I congratulate myself most highly to be able to place before your eves and subject to your sagacious judgment, this, if I may say so, new marvel of nature, this hitherto unknown mutation of Fragaria vesca. I send you some nodes of this Fragaria, collected by me, and a living root and at the same time a newly published little work of mine in botany (Manuel de Botanique), all this on the advice of our experienced botanist, B. de Jussieu."
And Linnaeus replied, "Your Fragaria pleased me immensely. I cannot sufficiently marvel as to how it has arisen from Fragaria vesca."17
The discovery of the monophyllous Versailles strawberry, F. vesca (Figs.5-10, 11), growing among a collection of wood strawberries in his father's experimental garden at Versailles first started Duchesne on his Fragaria research. In 1761 Duchesne and his father had planted some seeds of the wood strawberry, which had been in the garden for several years, to see if white F. vesca berries were produced frequently from plants with red F. vesca berries. Since the Duchesnes had replanted them too soon and had taken poor care of them, the seedlings almost all died. The experiment having failed, Duchesne paid no attention to the few plants which survived until their flowering time in 1763. Among them, on July 7, 1763, he found single-leaved F. vesca. By carefully planting all the runners, he had more than sixty living plants by the spring of 1764, of which about a third gave flowers and fruits in the normal season. Father and son planted mature seeds of it on June 15, 1764, and six weeks later saw seedlings with simple fourth and fifth leaves like the first. "One can judge how my surprise increased," wrote Duchesne. "I was expecting no such constancy. I began by doubting that it was general, because of the small number of plants I had raised, but seeing the experiment repeat itself, in our garden as well at the Trianon, the King's Garden, at M. de Jussieu's, and with several different interested people, it was necessary to give in and recognize the existence of a new strawberry with simple leaves, which reproduced itself constantly by its seeds."18
Here was experimentally supported refutation of the doctrine of constancy or immutability of the species as preached by the naturalists of his day. The Versailles strawberry was conclusive evidence that variations in a species could come from seed and that these variations were preserved in successive generations. How should one classify the new strawberry? The question led Duchesne into a dissertation on the meaning of variety, species and genus in which he pled for unilateral agreement of definition.
By means of hybrid sterility, so the naturalists believed, nature prevented the formation of new species. Not only did animals of different species ordinarily refuse to mate with each other, but when they did mate, their hybrid progeny resembled both father and mother but could not reproduce themselves. In regard to plants, Duchesne said, the doctrine of the fecundity of hybrids had replaced the law of constancy for the past twenty years, but he objected that the proofs of hybrid fecundity in plants were unreliable. No he could offer the fertilization of F. chiloensis by F. moschata as experimentally supported and respectable evidence. He only was waiting to see if the seeds of this cross would be fertile like the parents. He believed that the cross of F. chiloensis x F. virginiana would be a second example. Linnaeus himself was put under fire in the book when Duchesne criticized the great naturalist for arbitrarily naming new species and identifying the parents of the hybrid by using subjective judgments based only on the appearance of the plant an not upon experimentally supported evidence.
Duchesne's Fragaria study had convinced him that "species appear fixed and immutable, but that accidents which make certain individuals vary, procure in others rather considerable changes which are perpetuated in their posterity, which thus form a new species." In agreement with Buffon, famous French botanist, Duchesne said that "the crosses (metis) derived from the mating of two individuals of different species, but of the same genus, truly become the parents of new species, but the hybrids (hybrides) produced by individuals of different genera are deprived of the faculty of self-reproduction ." From this conclusion Duchesne went on to recommend a method of distinguishing genera from species (or varieties) based on experiments in plant breeding. "The best without doubt for plants as well as for animals would be to make the experiment of mating," he said. "Those which together produce fertile crosses (métis) would be pronounced of the same genus an those which refused to do so would be regarded as different genera. It is to be hoped that experiments of this nature will increase. Botany could only gain a great deal from them."19
As such experiments were difficult, time-consuming and almost impossible for many plants, botany had taken recourse in examining those parts of a plant which distinguished it from other kinds. But Duchesne even proposed modifying the usual method of distinguishing among genera by the number, shape, proportions and locations of their various parts. Instead, he recommended that the classifiers look first at the positions of plant parts and at their interior structure, since these characters should be as constant in plants as in animals, for which comparative anatomy served to distinguish among genera very well. Linnaeus had approached this suggestion in his statement that the inflorescence, or the arrangement of the flowers, revealed the most real differences. Why, then, asked Duchesne, were there so few differences so established in his works? Probably because he created too many genera and took for generic characteristics those differences caused by the influence of climate and cultivation, as these traits were perpetuated in the posterity of these plants. Such groups of plants, according to an axiom of Ray, another naturalist of the period, were qualified by the name "genus" since they could not be treated as varieties or as constant species. In the mid- 1700's the botanist was really a classifier who derived his conclusions from the observation of the world as he saw it. Duchesne was ahead of his time, a scientist of the age of experimentation, when naturalists would ask how nature became as it is and would try to duplicate the process in their laboratories.
Although Linnaeus did not change his earlier statements, he did continue to correspond with Duchesne, tolerating the youth's brash challenges. Linnaeus planted Duchesne's gift of the single-leaved Versailles strawberry in a bed in front of the main building at Hammarby where the famous Peloria had been planted, a specimen which also confronted the doctrine of constancy of the species, although Duchesne called it unsatisfactory evidence as its progeny were not fully or consistently fertile.20
One of Duchesne's questions about the lines of plant development was whether a profound change in climate or soil could so alter a group of plants, isolated from the environment of its parents over a long period of time, that an entirely new species would result. He suggested that the effect of soil and climate in America had altered European F. vesca into F. virginiana and that European F. moschata had there become F. chiloensis . He hoped that future experiments in cross-fertilization would clarify the question. Erroneous as his theories on the origin of F. chiloensis and F. moschata may be, Duchesne had recognized the effect which isolation of a species, under altered environmental conditions, can have in preserving adaptive changes in plants, a principle appreciated by geneticists today.
Duchesne also showed foresight in his conviction that a fixed temperature could be determined to tell when strawberries would germinate, release their pollen, flower, etc. Michel Adanson, the great French naturalist and contemporary of Duchesne, had done this for certain other plants. In 1766, Duchesne wrote that he himself had not yet been able to discover these temperatures for strawberries. He tried to explain the everbearing quality of the strawberries of the Bargemon Alps by this reasoning. Since the temperature necessary for the flowering and fruiting of strawberries remained the same there from spring until winter, instead of becoming increasingly warmer accompanied by a sharp change with the approach of autumn as in the rest of the temperate zone, the plants continually flowered and fruited in these mountains until fall. To test this theory, he sent specimens of the strawberries in his collection to a correspondent in Bargemon to learn if the climate would produce an everbearing quality in them as well.
First-hand observation of the development of a new variety of strawberry from seed -- the Versailles strawberry (F. monophylla) -- led Duchesne to construct a theoretical genealogical tree (Fig. 5-12) which explained how all the different sorts of strawberries he knew were derived from a single kind -- F. vesca semperflorens (the everbearing wood strawberry)
For each of the races of strawberries I have been careful to indicate what seemed actually true on the subject, but I do not dare flatter myself with having always been accurate. To do this well, it would be necessary to have certain and precise knowledge of the native country of each strawberry, or at least from the time it has been raised from seed, and to know from which other strawberry this seed has resulted. I have demonstrated how much insight is still lacking about all this ... One must first recall that I consider the alpine, Fraisier des mois I (F. vesca semperflorens) as the father of all the others. It is also at the head of the tree. The common wood strawberry, Fraisier de bois II (F. vesca sylvestris) which differs almost solely in its slower rate of growth [and in not flowering throughout the season he might have added], is immediately below, as if produced by it.
Duchesne considered the variegated and the white to be varieties of F. vesca. The double, the cluster, the Plymouth, and the "coucou" or abortive all seemed to him to be variants of F. vesca, the common wood strawberry. The Fressant, runnerless, and Versailles he considered to be simply varieties of F. vesca. But all these varieties, having several common characteristics, can thus be easily reduced to one common root. These are several branches of a single house. The ordinary Fraisier de bois (F. vesca sylvestris) is the only one of the eleven which grows naturally in wild places like the Fraisier des mois (F. vesca semperflorens).
The green strawberry VI ought to form a separate line. I have said that it seems to hold particularly to the Fraisier des mois, as its vegetation is a bit more vigorous than that of the Fraisier de bois.... Other particular characters whose causes can hardly be determined, throw still more indecision on the origin of this strawberry. Here [in the chart] I suppose it to descend immediately from the Fraisier des mois.
If the musky strawberry (Capiton VII) is not a plant originally distinct in origin from the (common F. vesca) strawberry, we must believe that it is derived from the green strawberry (F. viridis) rather than any other, as one sees it in the genealogical tree....
The Fraisier ecarlate X (F. virginiana), which is the common strawberry of Canada, and Virginia, differs, as I have shown, from the Fraisier de bois by a great number of minor characteristics. However, it can hardly have originated from any but this race, and so I mark it in the genealogical tree. The influence of climate seems to have produced the principal changes in it, since [such changes] are equally apparent in the two other American races.
... The Chilean (F. chiloensis ) (VIII) originates from the Capiton (F. moschata ) as does the Scarlet (F. virginiana) from the wood (F. vesca sylvestris). Indeed, it seems to have been subject to the same changes by the influence of the same climate, and the separation of the sexes on the Chilean males and females indicates this affinity.
The pineapple (F. ananassa) IX presents an affinity of a different nature [in the genealogical tree], because I suspect it to be a cross (métis) of the Scarlet (Virginiana) and the Chilean. I have stated the reasons for this: It resembles the former by its leaves, its stems, its flowers, and their sexes; it approaches the latter by its vigor and by all the qualities of its fruits -- size, color, substance, and perfume.21
Duchesne's arrangement of Fragaria with diploid F. vesca kinds followed by hexaploid F. moschata and finally by octoploid American sorts -- F. virginiana and F. chiloensis --is supported today by genetical studies.
Duchesne's L'Histoire Naturelle des Fraisiers of 1766 lists ten species of strawberries and nine varieties. In an article in the Encyclopedie Methodique Botanique of Lamarck, which appeared only five years later, he lists twenty-five kinds of strawberries. Duchesne rearranged his classification system in this later and much more widely known article, based on his continued research in Fragaria. He divided Fragaria into two main groups: (1) Les Fraises -- the pure wild strawberries with small and numerous ovaries and short stamens, and (2) Les Caperons -- strawberries with large but few ovaries and with long stamens. The first group was composed of eight sorts. The second group was divided into four subgroups -- the Maujaufes (F. vesca x F. viridis), the Breslinges (F. viridis), the Caperonniers (F. moschata ), and the Quoimios, the American species and hybrids, in that order.
(1) The Maujaufes were the link between the Fraises (the first group, F. vesca) and the Breslinges (F. viridis), and resembled the latter especially in their tendency to sterility, in their variability when raised from seed, and in their long, slender branches which bent with the weight of the fruit. They also resembled F. viridis in the large number and the arrangement of runners, in the long sepals which clasped and adhered to the fruit and in their watery flesh. In their small size, juicy tender flesh, bright red fruit color, and leaf color, they resembled F. vesca. The Maujaufe de Provence (F. bifera) and de Champagne (F. dubia, Fig. 5-13) were the two varieties Duchesne placed in this group.
(2) The Breslinges or green strawberry (F. viridis) had greenish fruit which turned red only when exposed to direct Sunlight. The berries had extremely large ovaries, scattered fairly sparsely over their surface, and a very juicy, very firm flesh. The long calyx was so tightly clasped about the berry that it could be detached only with difficulty. The leaves were drier and firmer than those of F. vesca and the Maujaufes, with a duller, browner color, and they were covered with longer hairs. One portion of the berry frequently aborted and in general the green strawberry proved extremely variable when reproduced from seeds, although sometimes it reproduced exactly. The first of the Breslinges-coucou (F. abortiva) was an intermediary berry between the Maujaufes (F. viridis x F. vesca) and the Breslinges (F. viridis). Then followed the Breslinge d'Allemagne (F. nigra of Germany), de Bourgogne (F. pendula), de Long-Champ (F. hispida), d'Angleterre (F. viridis from England), and de Suede (F. pratensis Linn.).
(3) Duchesne listed two Caperonnier (F. moschata ) varieties: First came the Caperonnier Royal, a twice-bearing one from Brussels and the only hermaphrodite F. moschata he knew; secondly, the unisexual Caperonnier (F. moschata dioca.)
(4) Then came the Quoimios, the strawberries of the New World, and their varieties from crosses, "of which none is constant, but which among them form a very recognizable race, intermediate between those of the Chilean and the Quoimios of Virginia," said Duchesne. "These two can be regarded as extremes, the first with very large fruits and very hairy foliage, the other with much smaller fruits and very smooth foliage ... the Quoimios are all rather subject to sterility, especially those raised from seed. As for the rest, one can hardly cite a common characteristic among them."22 The six Quoimios were comprised of the Frutiller, or Chilean (F. chiloensis ), the Quoimio de Haarlem (F. ananassa, F. chiloensis annaeformis), de Bath (F. calculate), de Carolina (F. Carolinensis), de Virginie or Virginian (F. virginiana), and lastly, the Quoimio de Clagny (F. hybrida).
The publication of L'Histoire Naturelle des Fraisiers did not exhaust Duchesne's interest in strawberries. He continued to collect new specimens at the Trianon, the king's garden in Paris, to experiment with cross-fertilization, and to correspond with Linnaeus, whom he continually asked for new strawberries, especially those foreign to Sweden. Linnaeus' letters express his continual eagerness to obtain rare plant specimens from the Trianon collection and describe his pleasure when the plants arrived and grew successfully. Linnaeus' friend Bjornstahl visited the Duchesnes in the summer of 1769. Linnaeus wrote to Bjornstahl: "Give my regards to dear Duchesne, the amiable boy, who procured me the Calceolaria (from Chile), and which now stands in bloom and cries each hour, 'Duchesne.' Never has any plant pleased me more, never have I more carefully tended a plant in my window."23 Duchesne in turn had requested that Linnaeus send specimens of the common wood and the green strawberry.
In the autumn of 1765 Linnaeus did send some F. pratensis (the green strawberry) plants, which arrived in wilted condition and soon died. Apparently such a fate was common in the long uncertain shipments with their poor connections, for the letters frequently discuss the problem. Duchesne made repeated requests to Linnaeus for new material, including suggestions and directions for packaging methods which would insure freshness and specific instructions for addressing the plants for the fastest possible delivery to Versailles. "He even called upon the postal minister in order to achieve faster postal service, a subject which interested the French sovereign as much as strawberries."24
Eventually on April 13, 1767, Duchesne couldwrite that he had just visited the Trianon and seen three plants of the green strawberry from Linnaeus which M. Richard had saved. Their buds were ready to flower and Duchesne said he "devoured them with his eyes." In October he wrote that they had flowered onceand now were flowering again, having produced a total of three berries. Their runners had "multiplied infinitely." This Fragaria differed from all other specimens in his collection. Finally, Linnaeus sent him the common wood strawberry and Duchesne's thank-you note, the last of his extant letters to Linnaeus, (dated July 24, 1772, tells of his delight in the new strawberry plants which embellished his garden.24 Duchesne received these two specimens after publication of his L'Histoire Naturelle. He described them in the "Essai sur L'Histoire Naturelle des Fraisiers" included in Lamarck's Encyclopedie Methodique Botanique.
The senior Duchesne considered his son's varied studies as the necessary elements of a good liberal education. Now he wanted him to prepare for a worthy career and insisted that he study law. So when Linnaeus' friend, Bjornstahl, visited the Duchesnes in 1769, he found Antoine Nicolas a law student who "is already Baccalaureas and will be Licentiat within a month, after which his law studies will be finished, for botany is his avocation, while law is only for future advantage, since anyone who wishes to receive an important occupation has to have studied the laws."25 Like the young Frezier, the navigator and engineer who brought back the first F. chiloensis , Duchesne too had parental pressure towards law. Like Frezier he resisted, and after graduation turned back with relief to natural history.
His interests spread beyond strawberries to research in the cultivation of other plants. For years he had been adding to a calendar in which he recorded the seasons of growth and the appropriate time of cultivation for each plant. Requests from gardeners for copies of it persuaded him to publish in 1770 Le Jardinier prevoyant (The Foresighted Gardener). It sold for six sous and was a widely used almanac in the eleven successive years of its publication. Intensive research on gourds and experiments in their cross-fertilization followed, then a catalogue called Etrennes botaniques (Botanical Handbook), giving the common names, descriptions, and uses of four thousand plants which had been grown at the Trianon, arranged according to Bernard de Jussieu's natural method of classification. In 1771 came a list of seeds sold by M. Andrieux-Vilmorin, founder of the great Parisian seed house of today. Years later, Eliza de Vilmorin would write extensive descriptions of strawberry varieties of the mid-1800's for an illustrated article in Decaisne's Le Jardin Fruitier du Museum.
A wonderful opportunity came to Duchesne in 1776 -- he was invited to visit the famous botanic gardens of England with Abbe Nollin. The voyage produced the essay "Sur la formation des jardins," the source of Delille's verses on gardening.
Duchesne's father continued to direct his son's life and Antoine's choice of wife was made to comply with his father's wishes. As the father of five children he became interested in education. He could not forget the thorough tutoring his father had given him and he wanted the same experience for his own children. He and a friend wrote a Portfeuille des Enfants in 1784 made up of pictures, articles, stories, and instructive games intended to familiarize children with the arts and sciences.
Eventually Duchesne inherited the family post as superintendent of the king's buildings (Fig. 5-14). The French Revolution in 1789 put him out of work. Moreover, the list of suspects doomed for the guillotine included the name Antoine Nicolas Duchesne. At first he had sympathized with the aims of the revolutionaries. Then the anarchy of June 20, 1792, made him conscious of the horror and fanaticism which led to the beheading of the king the following January. Duchesne realized that he had been supporting the forces which killed the man whom he and his father had walked to Reims to see crowned king years before. Although a devout Catholic, Duchesne refused to support the clergy who swore allegiance to the Civil Constitution. Only the reputation of his scientific achievements saved him from beheading.
When quieter days arrived, Duchesne became a teacher. Soon after the revolution the Ecoles Normales were founded with the most revered scholars in France appointed to the chairs of learning. Duchesne was admitted to the bench of specially selected teachers. Later he taught at the Ecole Centrale at Versailles where he helped develop a "natural" method of teaching based on the study of the psychology of learning in children and, following methods used by Duchesne and his father on their children, it introduced a broad range of subjects to students at an early age. At Versailles and later at the Military Academy of Saint-Cyr he taught all branches of natural history -- mineralogy, geology, zoology, comparative anatomy, botany, and plant physiology -- and emphasized new findings on physical and chemical operations in organisms.
His writings ranged over studies of rural economy and agriculture and included descriptions of local geology, dissertations on the metric barometer with explanations of the new decimal calculus and measurement systems, a guidebook to Versailles, and an article on the cultivation and preparation of dry land rice.
The death of his wife and of his oldest and youngest daughters in rapid succession affected Duchesne's health severely. He retired from his position as Supervisor at the Lycee de Versailles and returned to Paris where he concentrated on the education of his remaining three children and on new research in natural history. At this time he was almost destitute. He had never been a good businessman, always too willing to sacrifice his own interests in transactions and to lend money and the results of his research to his friends for their work. His disinterest in money bordered on neglect. The Revolution had destroyed the inherited post of superintendent of the king's buildings. Forced to borrow money, he repaid his loans by selling his Versailles property at a loss.
His research was his life, and with increased frugality he continued to study. There were memoirs to submit on a European nomenclature for natural history with suitable names for economic plants. He wrote on the direction of plant growth, especially on the tendency of plants to turn toward light. He pursued his early studies on sterility in plants and their causes. He had organized his strawberry history around the characters which linked the different kinds. Now he expanded this to studies of all organic life. Mean while he continued to help with the work of the Society of Agriculture of Versailles, of which he had been secretary for many years. Before the Society he read his articles on the cultivation and use of different species and varieties of potatoes, on decay in grain, on the industry of man and the instinct of animals, and a plan for a farmer's calendar.
With old age came successive illnesses, making him an invalid. Unable to rest idle, Duchesne tried to spend his mornings editing his cartons of extensive notes and manuscripts, but weakness hampered him. A series of strokes paralyzed him and affected his memory and his speech. He died in February of 1827, almost eighty years old. In a biography Baron A. F. Silvestre, the secretary of the Royal Central Society of Agriculture, said of him: "In dying he could applaud himself for having spent well his long career, and for leasing behind him useful literary productions which will perpetuate for a long time yet the memory of the services he desired to render to the friends of the natural sciences and to his country."26
1 Duchesne, Antoine Nicolas, L'Histoire Naturelle des Fraisiers.
2 Hylander, Nils, Linne, Duchesne och Smultronen. Svenska Linne-Sallskapets Arsskrift 28, 1945.
3. Duchesne, op cit., Part II, p. 28
4. Ibid.,p. 29
5 Hylander, op. cit.
6 Duchesne, op. cit. During this period the F. moschata had some popularity in English gardens. Either the English had solved the problem of dioecism unconsciously, by allowing male plants to remain in their gardens, or by calling another strawberry by the name F. moschata .
7 Hylander, op. cit.
8 Duchesne, op. cit., p. 40.
9 Duchesne, op. cit., Part 1, p. 187.
10 Ibid., p. 157.
11 Ibid., p. 179.
12 Ibid., Part 11, p. 42.
13 Ibid., Part 1, pp. 179-180.
14 Ibid., Part 11, p. 43.
15 Ibid., Part I, pp. 196-197.
16 Ibid., p. 203.
17 Hylander, op. cit., p. 19.
18 Duchesne, op. cit., Part II, pp. 12-13.
20 Hylander, op. cit.
21 Duchesne, op. cit., Part I, pp. 220-227.
22 Duchesne, Antoine Nicolas, "L'Essai sur L'Histoire Naturelle des Fraisiers," Encyclopedie Methodique Botanique of Lamarck. Jean Baptiste, Paris, 1783-1817, p. 534.
23 Hylander, op. cit.
7 26 Silvestre, A. F., Notice Biographique sur M. Ant. Nicolas Duchesne. Paris, 1827, p. 26.