A talk delivered at the New York Botanical Garden on November 15, 2015
At a recent talk at the NYAM, attended by several people in this room, the speaker claimed that Alexander von Humboldt (1769–1859) has been forgotten in our time. No doubt that Humboldt is not as well known as, say, Drake, but I flinch a bit at this conceit. How many of you in this room have heard of Alexander von Humboldt?
How many of you have heard of another German, living at the same time as Humboldt, i.e., Johann Friedrich Blumenbach (1752–1840)? (And out of curiosity, how many of you know who Drake is?) Whereas Alexander von Humboldt has been the subject of several monographs and has featured as a protagonist in Daniel Kehlmann’s excellent novel, Measuring the World (2005), which became a film in 2012, Blumenbach has never been the subject of a monograph, let alone the protagonist of a novel. If awards were being given out for “forgotten scientist,” then Blumenbach would surely receive one before Humboldt.
Some scientists, however, if not deserving to be forgotten, are at least are not worth spending too much time remembering. But Blumenbach is not one of those scientists. For one, he was Humboldt’s professor, training him in the life sciences at the University of Göttingen. And he wasn’t just Humboldt’s professor, but one to some of the most important natural philosophers in the late eighteenth and early nineteenth centuries, introducing fields like comp anatomy, physical anthropology, and physiology. What’s more, Blumenbach was the author of the best-selling textbook on natural history in Germany around the turn of the nineteenth century. His Handbuch der Naturgeschichte (Manual of Natural History) was first published in 1779, thereafter enjoying twelve more sanctioned editions, not to mention several translations. The Mertz Library holds the English translation in its collection and it is on display today.
These introductory remarks are meant to suggest that Blumenbach is, indeed, worth remembering, and today I will discuss his work on Conferva fontinalis, in particular. This yellow-green alga is the star of his essay, entitled “On an Extraordinarily Simple Manner of Reproduction,” which was published in the Göttingen Magazine for Science and Literature in 1781. Another Humanities Institute Fellow, Claire Sabel, and I have translated this article from German into English for the first time. This little essay has hardly garnered any scholarly attention over the years, such that our translation and my discussion is surely pulling it back, if just a little, from the brink of extinction. I hope to show why this effort is worthwhile.
My presentation falls into three parts. First, I will present some results regarding the status and classification of algae in the eighteenth and early nineteenth centuries. Second, I will discuss Blumenbach’s observations and experiments regarding C. fontinalis and set it in a larger context. Third, I will propose that there are reasons for taking the C. fontinalis as a proto-model organism. I will conclude in this vein, noting the trajectory this alga takes after Blumenbach.
I. Classification of Algae
The joy of historical research is that it can lead down the most serendipitous paths; the converse being, of course, that it leads to just as many or even more dead ends. This section is the product of the former. What I want to do is convey some highlights of my serendipitous path, which will begin from an obscure German tract on the study of cryptogamous plants from 1797 and end in 1850 with a poem. This is a Science-Humanities talk after all, and I’m not letting you escape without reciting a bit of a poem, about seaweed no less. The point of all this is to present some historical context for Blumenbach’s essay on Conferva fontinalis. While his essay concerns the physiology of the organism, most of the concerns of the present section are taxonomic. I was eager to understand how these plants (in eighteenth-century terms) were viewed at the time and how they were thought to fit into the vegetable kingdom in general.
An important contributor to study of algae and Conferva in particular was Wilhelm Albrecht Roth (1757–1834), who produced a small tract in 1797, entitled Notes on the Study of Cryptogamic Aquatic Plants. I was intrigued by the “Notes” part, which meant that it likely wasn’t 800 pages long like most books in the eighteenth century.
Other words in the title also give pause, namely, “cryptogamic.” It refers to Linnaeus’ taxonomic system, in which the first 23 of the 24 classes are organized according to the number or arrangement of the plant’s reproductive organs. These first 23 classes are referred to as phanerogamous because the reproductive organs (stamens and pistils) are visible to everyone, or, in the translation of Erasmus Darwin, the "marriage" of the plants is "public." This contrasts with the last, 24th class of plants, the cryptogams, or, in Darwin’s translation, "clandestine marriages," in which the organs of reproduction are either missing altogether or not visible. In Linnaeus’s Species plantarum of 1753, the class of cryptogamia comprises four orders: ferns, mosses, algae, and fungi. Algae are distinguished from the other orders in that they are root, stem, and leaf, all in one. The organism important for Blumenbach, C. fontinalis, is included under the algae, “fontinalis” being the second species included under the genus Conferva. I’ll note here that the order Algae included several organisms that would not be considered as such today, such as lichen, and it is, in fact, Roth, who first argues in his essay that lichen should be separated into their own order (18).
What all of this amounts to is that while Linnaeus’s system was by no means the only taxonomic option in the eighteenth century, it was the predominant one, and its fulcrum was the sex lives of flowers, which meant that any plants that were getting married in secret, the cryptogamia, were not of central concern. Linnaeus says variously that they were excluded by the Creator in the theory of stamens, that they are generally suspect (“of a dangerous quality” according to the author of a popular introduction to botany (Lee 1810), ferns and mosses are disagreeable on account of their strong smell, fungi are “dubious food,” and algae are mostly inedible and many are purgatives. Finally, Linnaeus says that if the vegetable world were represented as nine nations, then algae would be slaves, occupying a position just above fungi, the vagabonds.
The Linnaean framework and low estimation of algae and the other cryptogamia discouraged their investigation until the end of the eighteenth century. Indeed, James Edward Smith, notable in this context for having removed the hepatics from the order of Algae, was the first president of the Linnaean Society of London and delivered his “Introductory Discourse on the Rise and Progress of Natural History” on April 8, 1788. He praises the pioneering research of Micheli and Dillenius on various cryptogamia, whose books are on display today, but notes that the fungi and confervae in particular remain the “opprobrium of botany” (Smith 1791: 34).
This state of affairs did not escape the notice of Lewis Weston Dillwyn (1778–1855), who excused Linnaeus’s insufficient treatment of Confervae, saying that Linnaeus already had his hands full not just with the flowering plants, but also with the rest of nature in all its kingdoms. In Dillwyn’s work, British confervae, which comprises a series of fascicles first published in 1802, we thus find an unmistakable shift toward the intense study of cryptogams and, as its title suggests, of Confervae, in particular. It contains remarkable drawings of the Confervae and the book is on display today. Further evidence is found in its opening pages, where Dillwyn hails the genus Conferva as the “most beautiful and curious” of the Algae (Dillwyn 1809: 2). If that alone weren’t enough to prompt its study, he counts all the ways that do: first and foremost, he says, no genus will be found more interesting than Conferva. Its study, he says, quoting Smith, “relieves the mind among the busy pursuits of active life” (3). The genus, moreover, is a constant source of amusement, and it, in the end, like all natural history, produces satisfaction in the mind and leads the naturalist to “admire and adore” the works of God.
Of the two authors that Dillwyn thinks deserve particular attention because of their study of Conferva, Roth is signaled out, especially for his Catalecta botanica, which is three parts, the first published in 1797 and the second on display today, for it is the volume in which he specifically discusses C. fontinalis (though the drawing is of another species, since he does not provide one for C. fontianlis). So, we are returned to Roth and his Notes on the Study of Cryptogamic Aquatic Plants that I mentioned above. The Introduction of this text is quite remarkable because it details Roth’s own struggles with the study. Whereas Dillwyn, for instance, credits him as one of the best in the study of Conferva, even though he will thoroughly critique Roths’ work, Roth complains that he had been entirely without a guide, without resources, without hope in the face of studying an entirely too difficult species of plant. He says that he faced so many obstacles he nearly abandoned his research altogether. It seems, though, that once Roth began his collection, investigation, observation, and comparison of these algae, it was only his “18-week, quite perilous stay in a sick bed” that gave him time to publish the first part of the Catalecta botanica.
The Notes, then, reflect on his trials and tribulations with the cryptogamic water plants in order to produce a manual for the novice plant researcher: to give them the resources he didn’t have. To fulfill this intention, the work outlines how to describe the plants according to their inner and outer structure, in their dry and fresh condition, how to remove them from the water and put them under the microscope without damaging their parts. It provides a review of the foregoing literature, introduces the known species, and gives the relevant criteria for identification. It lays out the resources necessary for gathering the plants and how to set up a collection of them, since comparison, according to Roth, plays a necessary part in identification. The manual further notes how to preserve species in glass or dried in order to make the collection as “beautiful and perfect” as possible. He finally gives some pointers on how to draw the specimens. He closes the Introduction as follows: “If this essay induces the plant researcher to spend a greater amount of concentration on this family of the plant kingdom than has occurred before now, then my ardent desire to become useful to this science is completely fulfilled and the intention of these pages achieved” (Roth 1797: 12).
Roth turned out to be kind of fun, so I browsed the catalog to see what else was available. I found another work beginning with “Notes,” which was promising and rest of the title was even more so. It read, “Notes on the Internal Structure of the Conferva and its Manner of Propagation,” and was from the very first volume of the Journal für die Botanik. The article, though, had been excised from its original binding and rebound with other 19th-century works on algae by The NYBG library sometime in the early 20th century. This work, appropriately titled, Pamphlets on Algae, is likely an anthology unique to the Garden, like the many other similarly anthologized works with which it shares stack space.
It was when I was paging through this volume that I came across the poem by Eliza Cook, “The Song of the Seaweed.” The first stanza of the poem stands as an epigraph to John Hooper’s Introduction to Algology, which was published in Brooklyn in 1850. It is on display today and I think the cover remarkably bears the signature of Hooper himself. [Hooper, something of a Brooklyn hipster, was into algae before it was cool.] Although nearly everything has changed in the past half century regarding algae, Hooper still begins his work with a justification for the study of algae, arguing that they are just as worthy of our attention as the starry firmament above, because they, like stars, exhibit the “infinity of creation.” Like Dillwyn, Hooper also emphasizes the satisfaction given by their study. He quotes a colleague, “The naturalist knows nothing of tedium vitæ—that vampire ennui which renders life a burden to thousands. To him every hour is precious. He may have little leisure for his favorite pursuit; but even those scraps of time which occur in the busiest life, and which many allow to be lost, he gathers up as precious fragments” (12).
As remarkable as Hooper’s essay might be and his delivery of one of the first taxonomies of American algae, his essay’s epigraph, i.e., Eliza Cook’s poem, “Song of the Seaweed,” is all the more spectacular. I will read its first stanza, the one that begins Hooper’s essay.
I am born in crystal bower,
Where the despot hath no power
To trail and turn the oozy fern,
Or trample down the fair sea-flower.
I am born where human skill
Cannot bend me to its will;
None can delve about my root,
And nurse me for my bloom and fruit;
I am left to spread and grow
In my rifted bed below,
Till I break my slender hold.
As the porpoise tumbleth o'er me,
And on I go—now high—now low—
With the ocean world before me (1–14).
Whereas Linnaeus’s representation of the algae was as slave, Cook represents the algae here as refractory, not because the algae is itself particularly feisty, but rather because it is born and lives out of our reach. Yet, the rest of Cook’s poem nonetheless gives several vignettes of the resistance of the algae—it outmaneuvers a sailor when it is carried up on a rope to the ship’s mast during a storm but then flung to the shore near a lighthouse, the seaweed then outmaneuvers a young child intent on collecting it by being carried away by the tide, then hitches a ride on a whale that had just been speared, being freed from that creature, the algae then is taken away by a delightful starfish to a cavern of gems, the algae is then carried to the surface on driftwood and espies a stranded ship without any fresh water. The algae does not care for this one bit, saying “some hot brains are beginning to think/ of a messmate’s open’d vein.” The algae doesn’t care for this one bit and thus hitches a ride with a nautilus. But this spells the end for the seaweed, because it is then collected by some farmers, dried, and made into vraic or fertilizer. The once refractory seaweed—mostly inedible and otherwise cathartic—has become “a smoldering heap of treasure” for the farmer. The once refractory algae has been tamed and John Hooper sees it as a treasure for the algologist.
II. Blumenbach's Treatment of C. fontinalis
So far, I have mainly dealt with the historical taxonomy of algae and Conferva in particular as well as the associated attitudes toward cryptogamia and Conferva; Blumenbach’s essay, in contrast, does not concern itself with questions of taxonomy—he does not dispute foregoing classifications—but rather with physiology, i.e., the manner of reproduction of the Conferva fontinalis.
The reproduction of this organism caught Blumenbach’s eye, because he had been more attentive to the reproduction of organisms after the formulation of his Bildungstrieb or formative drive theory of generation, the first version of which he published in 1780, as an article in the same journal. In 1781, he published a longer version of it. He released a Latin translation of it in 1787. And, finally, he issued a second and third edition in 1789 and 1791, respectively. These two editions were substantially revised and represented what he called the “mature” versions of his theory.
In this chronology, what we find is that the formative drive theory, which I’ll explain shortly, was published before the essay on the Conferva fontinalis, which means that the alga did not lead Blumenbach to his theory. Nonetheless, the algae takes such a crucial role in his argument in all revisions of the essay from 1781 onwards that it arguably comes to play just as important role as the organism that Blumenbach identifies as having spurred the theory in the first place.
That organism was the polyp, now known as the Hydra viridissima, which was one, if not the most, famous organisms of the eighteenth-century. Its discovery was brought to attention by Abraham Trembley (1710–1784), a Swiss naturalist. His discovery was made while he was a tutor in Holland to the two sons of Count of Bentinck. He and the boys would collect bugs and plants to look at under the microscope. The boys, however, one day told Trembley that one of the supposed plants had walked across the jar. Trembley was quite puzzled, because it was green and seemed to be a plant, but it was also motile and seemed to exhibit other animal characteristics. He noticed that the tentacles of the polyp were not uniform across each individual and reasoned that they were akin to roots, which also weren’t equal in number across individual plants. If these were roots, he thought, then it would be possible to sever the tentacles and for the polyp to live and he would have confirmation that it was a plant; however, if it died, then he would have confirmation that it was an animal. To his surprise, neither of the two cases obtained. Rather, both the severed part and original individual regenerate their lost matter, both becoming again complete animals. Hence, as Trembley recognizes that the situation is unlike the regeneration already known in the crayfish, e.g., because its severed antennae do not themselves become again whole crayfish—only the missing part is restored. In the polyp, though, each severed part becomes a whole new polyp and the injured polyp completely restores itself. Trembley first communicates his findings in 1740 and an eloquent account of them are published in the Histoire de l’Academie des Sciences of 1741:
“The story of the Phoenix who is reborn from its ashes, fabulous as it is, offers nothing more marvelous than the discovery of which we are going to speak. The chimerical idea of Palingenesis or regeneration by Plants & Animals, which some Alchemists believed possible by the bringing together and the reunion of their essential parts, only leads to restoring a Plant or an Animal after its destruction; the serpent cut in half, & which is said to be rejoined, gives but one & the same serpent; but here is Nature which goes farther than our chimeras. From one piece of the same animal cut in 2, 3, 4, 10, 20, 30, 40 pieces, & so to speak, chopped up, there are reborn as many complete animals similar to the first.”
The polyp, in short, was a vexed phenomenon in the eighteenth century: it exceeded the expectations of naturalists and foregoing modes of explanation. How could this thing—plant or animal—regenerate itself ad infinitum? Trembley devoted himself to investigating these questions. His Memoires are an amazing record of his research. He recounts at one point, for example, that he was able to turn the polyp inside out. Supposedly, no one has been able to do this inversion again with much success. Today, we have the first of two volumes of his work on display, showing one of the remarkable illustrations of the polyp. Although he first communicated his findings in 1740, he did not publish this work until 1744. On the one hand, he was conducting the intense research already mentioned, which included finding out ways that he could safely transport living specimens across Europe so others could confirm his experiments. On the other hand, the book itself is lavishly done. When checking the condition of our copy here, the conservation librarians confirmed that fact. They were impressed.
Evidently, Blumenbach himself was not immune from the polyp craze. And it was the polyp that spurred his theory of the formative drive, and prompted him to convert from being a supporter of preformation to one of epigenesis. Preformation (evolution, encasement) and epigenesis are both terms that refer to theories of generation. As might be expected, “evolution” and “epigenesis” bear no relation here to their current senses. In short, a theory of generation at this time was meant to describes how new living beings came to be and how they developed over time.
“Epigenesis” was coined by William Harvey (1578-1657) in the seventeenth century, though it is a theory whose roots are much older. Although he exercised an epistemic modesty concerning how it actually occurred, epigenesis designated the generation of a germ from an undifferentiated primordium. Epigenesis was to continue to have this basic sense in the eighteenth century, though differently expressed in life scientists like Comte de Buffon, Pierre Louis Maupertuis, and Caspar Friedrich Wolff. What was important to understand about epigenesis in its eighteenth-century versions is that it signified the gradual development of plants and animals, such that one organ was thought to formed after another in a succession. This flatly contradicted preformationism, which reigned as the predominant theory for most of the eighteenth century.
Though also stated in some early forms, preformation was given a philosophical basis by Nicolas Malebranche (1638–1715) as a response to René Descartes’ (1596–1650) failed attempt at a mechanical explanation of generation. While mechanism could explain the motion of bodies and even their growth, Malebranche contended, that it could never explain the coming to be of the parts themselves and never of the whole living being. Preformation, then, at its core, attempts to do away with the problem of generation altogether by asserting that the embryo preexists, is preformed either in the egg (i.e., ovist preformation) or in the spermatozoon (animalculist or spermist preformation). To illustrate this, Malebranche invoked the image of nesting dolls, so that the embryo of any animal always already existed preformed in its parent, which already existed from the beginning in its parent, so on and so forth until we reach the original inhabitants on earth, which in the case of humans was none other than Adam and Eve. This meant that one or the other already contained the embryos of every human being within them.
Preformationism, then, had the virtue of according nicely with eighteenth-century religious beliefs as well as with its most popular scientific mode of explanation: if the embryo already existed, then it was quite possible to explain its development purely mechanically, without invoking any kind of spiritual or divine causes, at least except for the first one, in the Creation. Its chief proponents in the eighteenth century were Albrecht von Haller (1708–1777), Charles Bonnet (1720–1793), and Lazzaro Spallanzani (1729–1799).
It was Haller and Wolff, though, who represented the center of the war between these two theories of generation and their battlefield was the chicken embryo. Haller proposed a developed a sophisticated version of ovist preformation. It is interesting to note, though, that Haller was not always a preformationist. He started as one and ended as one, but he flirted briefly in between with epigenesis, a flirtation that was prompted by the most seductive of organisms, the polyp. Wolff, on the other hand, affirmed epigenesis, for which he formulated the vis essentialis or essential force, which drove he undifferentiated mass into a living being. Wolff and Haller both submitted careful experimental work to prove their respective theories, but neither of them were able to deliver a decisive blow to the other’s theory.
It was on this stalemate that Blumenbach’s theory of the Bildungstrieb was supposed to intercede. He says that the question of generation, with which he begins his treatise—“What occurs within a creature when it has surrendered itself to the most delightful of all impulses, and now, impregnated by a second shall, give life to a third?”—awakens the greatest curiosity within humans (Blumenbach 1789, 1). Since, he says, there has been so much reproduction that has occurred since the time of Adam and Eve, it is really quite humiliating that we don’t still know what it is going on.
He confirms this longstanding, pitiful state of affairs, remarking that already in the seventeenth century, Charles Drelincourt, Herman Boerhaave’s teacher, had gathered together 262 “groundless” hypotheses on generation from his predecessors and “nothing is more certain,” Blumenbach adds, “than that his own system amounts to the 263rd (Blumenbach 1789, 5). In order for Blumenbach to be able to articulate his answer to this age old problem, he must first make room for it by effectively dispensing with the difficulties that had hampered those foregoing theories, at least enough so that the Bildungstrieb does not become the 264th failed system. This requires him to refute previous theories of generation as well as to demonstrate how his theory overcomes the very weaknesses that made them untenable. To investigate the more than 263 hypotheses individually, however, would be an overwhelming and, ultimately, unnecessary enterprise, since Blumenbach thinks that all of them can be brought under two headings: of epigenesis or evolution (preformation).
Much of Blumenbach’s Bildungstrieb essay is a criticism of preformation, especially as it was advanced by Haller, but also of Wolff’s essential force. Much of the arguments on either side are sophisticated philosophically and experimentally. But some of the evidence that had been furnished to support preformation was not and Blumenbach aims not to criticize the evidence itself but the mode of explanation. For example, he relates the case, which had been recorded in the log of the Imperial Academy of Natural Research, where a miller's wife had been reported to have delivered a daughter with an engorged stomach. The baby suffered so immensely over the next eight days that most of those present thought that she was surely to die. Yet, in the meantime this sick baby gave birth to another baby that was, according to another report of the case, “the size of the middle finger” {Blumenbach:1789vjibid. ,, 51–52}. This case, incredible as it might appear, seems less so if one accepts the theory of preformation and, in fact, appears to be evidence for it. For this reason, Haller included the case among his evidence for preformation.
Blumenbach, however, thought it all too easy to meet such cases with more cases (Blumenbach 1789, 54, 57). Hence, he thinks that the entire mode of explanation should be considered dubious. These kinds of cases, even though they are published in reputable journals and are vouched for by authorities like natural historians and physicians, are unconvincing, since for every example offered, one can easily find a counterexample. Anecdotes aren’t arguments.
For Blumenbach’s comprehensive and vehement critique of preformation, one might think that he had also been a supporter of epigenesis. However, as he confesses, he had once been a preformationist, even defending its theories in his writings. It was, again, at least according to his own narrative, the polyp that spurred his conversion.
He recounts in his essay that he had been on vacation in the country. He gathered some polyps from the local stream in order to entertain his friends with the “wonders of this little animal” {*Blumenbach:1792uf ,, 17}. Because of the warm weather and hardy constitution of the polyps themselves, their experiments went off with great success. So much so that the act of regeneration seemed to become almost visible. “By the second or third day, the maimed and divided animals was so many new ones, each arms, body, tail, etc.” (17–8). This result, though, was expected, and rather than challenging his preformationism, it merely confirmed it. In fact, Blumenbach says that he performed the experiments to demonstrate the truth of that theory and show the “baselessness of gradual formation [epigenesis]” {Blumenbach:1789vjibid. ,, 20}. Yet, the experiment yielded an unexpected result: he noticed that the regenerated polyps and their arms were of a much smaller size, even though the creatures had been given ample food. This meant that the new limbs and body could not be the result of an aggregation of matter that merely filled in another preformed germ, because the new limbs were smaller than they had previously been, which could only be the case if they had been gradually formed entirely anew.
For Blumenbach, then, there did not seem to be any way to account for the diminished size of its regenerated body or parts if one supposes the existence of preformed embryos. How could they anticipate or respond to the polyp’s accidental severance of limbs? This regenerative or reproductive capability of living beings, i.e., their responsive adaptation to the contingencies of nature, did not seem to be assimilable by preformation theory in any possible guise. It appears, in fact, wholly anathema to the theory’s essential foundation.
No preformed embryos can exist, Blumenbach says. Instead, a new theory is required. He writes:
In the previously raw unformed generative matter of organized bodies, after the matter has reached maturation and the position of its determination, a particular drive that is operative throughout life becomes active, by which organized bodies receive their determinate form in the beginning, then maintain it throughout life, and, where possible, reproduce it if they somehow become mutilated.
A drive that consequently belongs to the life forces, but that is just as clearly different from the other kinds of life force of organized bodies (contractibility, irritability, sensibility, etc.) as from the universal physical forces of the body in general; this one appears to be the most important force to all generation, nutrition, and reproduction, and it can be designated with the name of Bildungstrieb (nisus formativus), in order to differentiate it from other life forces.
These remarks thus introduce the Bildungstrieb. It is responsible for giving and preserving the form that organized bodies have while alive as well as restoring that form when damaged. In this respect, it is essentially operative in the processes of generation, nutrition, and reproduction, processes that correspond to those just named, i.e., the initial determination, subsequent maintenance, and restoration of organic form. It shapes living beings into what they are and what they will, and reproduces that form when it is mutilated. Although Blumenbach associates it with the other Lebenskräften, he clearly intends the formative drive to be considered as distinct from them as well as from physical forces in general. This is emphasized by the use of the term “Trieb” (drive, impulse), rather than “Kraft” (force, power).
Although this theory might not seem like much, the Bildungstrieb became a fundamental concept in defining the organism concept in the latter half of the eighteenth and early nineteenth century. It influences philosophers (Immanuel Kant) and natural scientists (Wolfgang von Goethe, Friedrich Kielmeyer) alike, so much so that the 1824 entry for “Organism” in the Brockhaus Lexicon, a popular German encyclopedia, would still heavily rely on Blumenbach’s theory.
Yet, if we return to Blumenbach’s doctor-on-holiday narrative, we may ask whether a strong enough impetus exists within it to elicit his conversion. Although the narrative is quite compelling, we might ask whether these events are really enough to explain Blumenbach’s conversion? That is, there are two questions. First, has Blumenbach decisively refuted preformation? In particular, has he conclusively dealt with the seemingly unassailable strategy of preformation to appeal to an ever smaller and always invisible preformed germ? Second, even if he has refuted preformation, has Blumenbach proved the truth of epigenesis? I contend that although Blumenbach might have been converted through his experiments on the polyp as detailed in his narrative, these experiments alone offer no clear advance over other, already extant counterexamples and criticisms of preformation; he has not yet sunk the invisible preformed embryo, and the truth of epigenesis remains outstanding. I think, though, that Blumenbach’s introduction of the Conferva fontinalis solves all of these difficulties.
The essay that Claire and I translated, “On an Extraordinarily Simple Manner of Reproduction” details Blumenbach’s description of the Conferva fontinalis’s reproduction. Already in this essay, however, Blumenbach notes how his findings confirm the Bildungstrieb theory. In his revised editions of the essay on this drive, the Conferva fontinalis comes to play a central role.
For Blumenbach, everything about this alga is einfach, i.e., mostly in the sense of “simple” but also “easy”: it is a word which appears in the essay’s title and appears throughout the essay. He writes, “The observation concerns the extremely simple manner of reproduction of a just as simple plant, i.e., one species of algae” (Blumenbach 1781). This emphasis on simplicity is carried over to the Bildungstrieb essay. What we need to see then is what is so simple about its manner of reproduction and the organism itself.
First, the algae is simply found and attained. Blumenbach says that it is “found frequently in the spring, particularly in the the effluence of water pipes, springs, ditches, ponds, etc” and that even unbotanical readers (like me) could easily be reminded of it. He references Micheli and Dillenius, whose drawings are on display here, but credits his drawings with being much more accurate.
Second, the morphology of it is simple. Blumenbach writes,
The whole plant consists merely from a simple (never divided), mostly straight, about half-inch long, exceptionally fine but fairly solid filament of a beautiful bright green color, which is usually rooted with its bottom end in the mud. Because, however, these filaments mostly stand next to one another so many thousands thick, they clump together, just as in the figure here they look like a fine-haired fur…. When it is pulled from the water, and the filaments laid down, it looks dark green, slippery-smooth, and almost like wet mouse fur. (Blumenbach 1781)
Moreover, this wet mouse fur had an identical internal and external form that was translucent:
The internal structure of this moss is just as simple as its external form. Even at the strongest magnification and in the brightest light, absolutely nothing more is visible in the whole plant than a fine vesicular texture, almost like a green froth or foam, which is enclosed by an extremely fine, nearly imperceptible external membrane. (Blumenbach 1781)
Blumenbach informs us that he kept his specimens in sugar jars and looked at them under Wilson’s screw-barrel microscope, a single lens microscope that was popular due to its portability. It is impossible to determine exactly which model Blumenbach had and what its magnification capabilities were; nonetheless, the University of Berkeley offers these images. The first is taken from Wilson’s screw-barrel microscope and the second through a modern compound microscope. Counter to what one might expect, magnification was not the biggest limitation to microscopes; rather, it was, in the first place, accessibility. These were often luxurious machines made of fine materials that were primarily available to the affluent. Technically, the microscopes suffered from chromatic aberrations and other difficulties in optics that made the images less sharp and more prone to artifacts, as seen in this image. Also, techniques like staining were not well developed, which also hampered the advantage of the microscopic work. Finally, these microscopes, of course, did not provide their own light source. This screw-barrel model was used by holding it up to the light, as shown here. On display today is Henry Baker’s guide to microscopy, which went through multiple editions in the eighteenth century. The displayed page shows the kind of microscope that Blumenbach would have used. The title page of Baker’s book is also worth mentioning, because, besides reading like a carnival barker’s pitch, it reveals the enthusiasm he and a larger public had for microscopic study at this time. His book, moreover, did not only discuss the optics and models of microscopes, how to use them, etc., but also provides a catalogue for all the popular things people liked to look at under the microscope: fleas, the circulation of blood, spermatozoa, and, of course, polyps. In fact, there was a bit of a controversy between Baker and Trembley, because Baker, after learning of Trembley’s discovery of regeneration in the polyp, actually published his own studies on it before Trembley released his own. Seemingly, no one can escape the pressures of publication!
Let us return now to the simplicity of Blumenbach’s C. fontinalis. Third, as the title suggests, the algae’s manner of reproduction is also quite simple. It takes place within 48 hours, which makes it easy to observe. Blumenbach describes it as follows and provides the corresponding drawings:
I noticed … that a piece of this moss-fur that I had already kept in the jar for a couple of days seemed to have gradually powdered the outermost surface of the glass every now and then with a dark green dust (see figure I, on the left). After closer investigation I became aware that this was the extraordinarily simple manner of this moss’s reproduction. The tip of such a filament (fig. 1) swells up into a small egg-shaped nub (fig. 2), which separates from the filament after some time (fig. 3), fastens itself to the next, most favorable location (fig. 4), and before long again drives out a tip itself (fig. 5), which elongates itself more and more, almost visibly (fig. 6), until it at last has grown into a new, complete Conferva. (Blumenbach 1781)
C. fontinalis, then, is simple in attainment, morphology, and manner of reproduction. Blumenbach calls attention to this explicitly and explains why it matters, “Both the very quick growth as well as the transparent structure of the plant offered me the benefit of being able to see through it and watch its complete development entirely before my eyes” (Blumenbach 1781). He emphasizes that its internal structure mirrors its external one, that nothing more is visible in this thing through the entire course of generation than what meets the eye. All of this means that nowhere in C. fontinalis can a preformed embryo possibly exist. There is no trace anywhere of a wrapped-up filament waiting to unfold into a new alga. If the preformed embryo is wanting, then so is the preformation theory. That this organism develops seemingly by itself out of an unformed substance proves the truth of epigenesis and his Bildungstrieb theory.
Whereas the much more complicated chick embryo, the locus of debate between Haller and Wolff, has the disadvantage (relative to observation) of beginning not just within the egg, but within an egg within the hen, nothing of the Conferva fontinalis is barred from view. Blumenbach thus attempts to circumvent the obstructions in their debate by choosing an organism based on its simplicity. Again, the choice of the algae according to the criterion of simplicity is thus an attempt to forestall preformation’s rejoinder that preformed germs are present but unobservable, a claim that remains tenable as long as one can appeal to a more basic, underlying structure: the germ. But if the algae’s most basic structure is already visible on account of the organized being’s simplicity, as Blumenbach insists, then the rejoinder is futile. A formative drive is thus responsible for the generation, growth, and regeneration of not only C. fontinalis, but all living things.
In closing this section, I will make one final remark regarding the C. fontinalis. First, Blumenbach never uses the word algae in his essay. As you likely noticed, he often refers to it as a moss. The conceptual distinctions were much less determinate than now, a point that was already made clear with respect to the first section on taxonomy. This invites the interesting question of whether it is possible to identify what Blumenbach was actually looking at. I’m open to objections, since I’m not a phycologist, but the short answer seems to be that it is a species of the genus Vaucheria, which is in the Xanthophyceae class, i.e., a yellow-green algae. One source for this determination is a paper published in the British Phycological Bulletin that examined several specimens from the Dillenian herbarium. Dillenius’ work, again, is on display today, and it provided the basis for Linnaeus’s classification of Conferva fontinalis. Hence, if Christensen can identify the Dillenius’ specimen, then we can likely also know what the proper identification of Linnaeus’ Conferva fontinalis. Christensen names the specimen, Vaucheria fontinalis, an identification that remains current (Christinsen 1968). One difficulty, however, is that there is no way to determine whether Blumenbach correctly identified his species, for it could have been something else entirely. In sifting through the taxonomic literature, almost everyone has their own widely divergent idea of what the C. fontinalis is or is not. And debates rage whether this thing is a plant or animal or first a plant, then an animal, and then a plant again. Nevertheless, based on Blumenbach’s description, in consultation with resident phycologist Ken Karol, and some time floundering around in AlgaeBase, I am somewhat certain that Blumenbach has a species of Vaucheria before him. Robert Naczi also shared with me the following photo of Vaucheria in situ, which he collected in intertidal mudflats on the Rondout River, a tributary of the Hudson, and were positively identified as such by Ken Karol. On display, we have some herbarium sheets showing Vaucheria fontinalis as well as another species, which features an interesting drawing. In the future, I hope to make my own collection of Vaucheria and reconstruct some of Blumenbach’s experiments in order to get a better sense of what he saw in his sugar jars, the simple Conferva fontinalis that reproduces just as simply.
III. Conferva fontinalis as Proto-Model Organism
The final section of this talk fulfills its title: Conferva fontinalis as proto-model organism. This section will likely be the most contentious as well, since the term “model organism” did not emerge until the late 1980s, which is to say, about 200 years after Blumenbach’s essay. Is it not the grossest form of anachronism to attribute a thoroughly modern concept to Blumenbach’s alga? On the one hand, when we return to study life science in the eighteenth-century, the risk for anachronism abounds, for the very concepts wholly fundamental to contemporary biology are absent: e.g., there’s no genetics, evolution, or cell theory. “Biology” in its modern sense won’t be used until 1802 (1800 in a footnote), which still predates anything like the discipline of biology by at least a half century. And, although I’ve liberally used the concept “organism” when referring to Blumenbach’s 1781 essay, that concept, in sense of a living individual, did not yet exist, but only began to gain prominence in the 1790s. In fact, Blumenbach in his categorical distinction between organic and inorganic laid some of the groundwork for the organism concept to gain currency. I am certainly aware of the dangers of anachronism, yet I still think there is a real case to be made here. On the other hand, to be clear, I am not saying that Blumenbach’s C. fontinalis is a model organism, because it is not, but rather that it is a proto-model organism (I am leaning heavily on the “proto” part). That is, in Blumenbach’s essay, we find that his justifications for the choice of organism and the representational target intended for the alga anticipate contemporary thinking on model organisms. If I can say this is the case, then Blumenbach not only anticipates the model organism, but he also is one of the first to use a “plant” in this way. The argument will proceed as follows:
1. What features are common to model organisms? What distinguishes them from experimental organisms?
2. Why is Conferva fontinalis a proto-model organism?
3. Whither C. fontinalis as proto-model organism?
The easiest way to introduce model organisms is by example, and specifically those recognized by the US National Institute of Health to be such. These include the mouse (Mus musculus), rat, zebrafish (Danio rerio), fruitfly (Drosophila melanogaster), nematode worm (Caenorhabditis elegans), and thale cress (Arabidopsis thaliana). We could also include Escherichia coli, yeast (Saccharomyces cerevisiae), and others.
More generally, model organisms are non-human species that are used to investigate a host of biological phenomena {Ankeny:2011ix ,, 313}. These investigations are intended to yield data and theories that are applicable to other organisms or to the organic world as a whole. Model organisms, then, are results obtained from investigating simpler organisms as models for what can be extended to more complex ones. What is true of the fruit fly might reveal something true of the fish, dog, or human.
Rachel A. Ankeny and Sabina Leonelli have done some of the best work I’ve seen regarding the philosophy of model organisms. One of their claims is to draw a distinction between experimental organisms and model organisms, which, although they agree in several ways, still differ according to their social conditions as well as their epistemological features. What an experimental organism is will become clear in distinguishing it from a model organism; however, loosely construed, it is an organism that stands as a subject of experimentation or observation for the sake of a specific result.
There are two ways in which model organism differ epistemologically from experimental organisms. These differences rely on the concepts of representational scope and representational target. Representational scope is how far the results from one organism can be applied to a wider groups of organisms. In philosophical terms, this is the question of how far a type can be extended to a token; i.e., what does the results concerning this bike reveal about bikes in general or all vehicles as a whole. Second, the representational target is the phenomena to be investigated in the organism. Ankeny and Leonelli helpfully illustrate these concepts through the example of Marcello Malpighi’s experiments on the frog concerning respiration. The representational target of his investigation is respiration, since it is the phenomenon to be studied. The representational scope, however, is respiration in mammals. The intention is that the findings concerning the frog will also be applicable to mammals in general. The difference between model organism and experimental organisms is constituted through the different in relation to these concepts.
- Model organisms are always taken to represent a larger group of organisms beyond themselves. This means that a model organism relies on specific claims regarding its representational scope. But this does not hold for experimental organisms, whose representational scope need not be taken into account at all. A scientist might be investigating the physiology of fur growth in poodles without concern for its applicability to other breeds or species. Model organisms never have such a limited scope.
- This second point is similar to the first. While experimental organisms have a specific representation target—i.e., that is, there is a determinate phenomenon to be understood (fur growth, in the pervious example), model organisms are not limited to a single phenomenon, but rather serve to explicate the organism as a whole in each of its processes, like its development and physiology. In short, research on model organisms is intended to extend to a wide class of organisms and wide class phenomena within those organisms. In light of this distinction, we must also recall what experimental organisms and model organisms tend to share: the chosen organism must be tractable, i.e., simple to acquire, simple to maintain, simple to manipulate, and relatively simple in structure.
Blumenbach, as we have seen, hits these lasts points. He emphasizes how easy it is to acquire these organisms. Just check your local ditch. Easy to maintain: just keep your sugar jar (today we might have to use a pickle jar) and plop them in and wait a couple days. Simple to manipulate: put them in the microscope and have at it! Simple in structure: the C. fontinalis is translucent, isomorphic inside and out, and reproduces in an “extraordinarily simple” manner.
The representational scope and target of the Blumenbach’s experiments and observations on the alga further suggest that this organism is closer to a model organism than just an experimental one, for the representational scope that Blumenbach intends for his research is living beings in general; that is, it refutes preformation as a viable theory and confirms an epigenesist theory by showing the gradual development of the algae. If this organism can be confirmed to reproduce gradually, then all organisms can also be confirmed to reproduce gradually. The representational target is also of a wide scope insofar as Blumenbach is not interested solely in the reproduction of the Conferva fontinalis but reproduction as it occurs in general. He intends his results to suffice to show that every living being exhibits the formative drive in its generation. Regarding the alga, Blumenbach writes, “One wishes that so many physiological experiments and experiences could be just as perceptibly and clearly proven, as straightforward, as irrefutable as this one here is for the credibility and efficacy of the formative drive!”
The account I have given, of course, is subject to several objections, which I am eager to hear and respond to; however, I will raise one here myself. Arabidopsis, E. coli, and the other model organisms are unique in having the support of large research communities, which involves a whole set of expectations concerning cooperation, definition of protocols, and a unification of researchers {Ankeny:2011ix ,, 318}. In short, there was seemingly no mass of researchers working on the Conferva fontinalis. If Blumenbach was flying solo with this alga, could it really be a model organism?
One of the interesting things about Blumenbach’s work on Conferva fontinalis is its reception. Of all the taxonomical work on algae that I reviewed in the first part of my talk, hardly any of it mentions Blumenbach’s study. This makes some sense, because Blumenbach’s work is physiological, not taxonomic. Yet, his essay does focus on the means of reproduction, which was important to classification efforts. Where his study does gain traction, though, is in some of the more cutting-edge investigations of plant physiology that look to new developments in chemistry and the study of electricity to furnish new methods for plant research. One such work is Johann Julius von Uslar’s Fragments of New Plant Knowledge, published in 1794, and translated the following year into English, under the title Chemico-Physiological Observations on Plants. The translation is on display today. This text affirms Blumenbach’s formative drive as well as underscoring the use of the alga as evidence. Uslar notes the importance of the organism being translucent, growing fast, having a simple structure and so on (Uslar 1795: 71). Blumenbach’s work on Conferva fontinalis also appears, of all places, in Erasmus Darwin’s Phytologia (1800). I say “of all places,” because my main project at the Garden concerns Erasmus Darwin, not Blumenbach, but here they are together. It is not that surprising that Darwin’s cites Blumenbach, for both are major contributors to life science at the end of the eighteenth century and were quite aware of each other. Blumenbach’s student translated Darwin’s Zoonomie into German. I am surprised that Darwin, via the translation of Uslar’s work, specifically mentions the algae in his section on plant reproduction.
Finally, though, Darwin draws another interesting connection, for he also discusses Conferva fontinalis with respect to Joseph Priestly’s green matter; that is, Priestly independently used Conferva fontinalis in his experiments that determined that plants produce oxygen and which played an important role in the articulation of photosynthesis.
Future research will further track Conferva fontinalis to see what other secrets it might hold, and that despite the fact that everything was against it as becoming a proto-model organism, it undeniably shares some of its essential characteristics.
In closing I will share one final twist to this story of this little filament. In the preface to the first edition of novel Frankenstein, Mary Shelley writes, “The event on which this fiction is founded has been supposed, by Dr Darwin, and some of the physiological writers of Germany, as not of impossible occurrence.” In the preface of the 1831 edition, she refers to a conversation between Percy Bysshe Shelley and Lord Byron on the principle of life as a source of the book. She says they were recounting an experiment done by Darwin, in which a vermicelli is reanimated. Shelly scholars have pursued with great zeal what this vermicelli might be, for somewhere along the line, perhaps in the conversation, perhaps in the writing, pasta got involved. Samuel H. Vasbinder, in “A possible source of the term ‘vermicelli’ in Mary Shelley’s Frankenstein” has one answer: it is Darwin’s experiments on the Conferva fontinalis. “It is possible,” he says, “that in the ensuing years [after the discussion in 1815, evidently filled with many tragedies for Shelley], such a tiny fact as ‘conferva fontinalis’! could have been so blurred that it evolved into what Mary remembered as ‘vermicelli’” (116). C. fontinalis as inspiration for Frankenstein! Vasbinder further adduces his claim by a linguistic analysis of the similarities between the two terms, c. fontinalis and vermicelli. Alas! against everything I wish in my heart, Vasbinder is dead wrong. Darwin does not discuss c. fontinalis in any respect to reanimation, which he does do though, with another organism, the vorticella. The linguistic similarity of this word and a theoretical position in much greater accordance with Shelley’s own recollection make it a much more likely candidate as the inspirational organism for Frankenstein. Alas! this is one of those dead ends that I mentioned can happen in historical research. If nothing else, though, I hope to have reanimated Blumenbach’s experiments and observations concerning C. fontinalis and some of the general scientific approaches to algae in the eighteenth century.
