Federico Cesi, founder of the Accademia Nazionale dei Lincei, was fascinated by ‘imperfect’ plants (that is, plants lacking evident organs of reproduction – flowers, seeds and so on), especially fungi. Cesi's planned treatise on fungi never appeared, but the drawings of fungi, mostly in watercolour, that he commissioned towards the end of his life passed at his death into the mighty collection of Cassiano dal Pozzo, thence to the library of Pope Clement XI, then to the Palazzo Albani, whence they were plundered by the French Revolutionary army, ending up, recorded simply as ‘watercolours and pen drawings … executed in the first third of the seventeenth century’, at the Institut de France. The true source of these volumes was first suggested by Andrea Ubrizsy in 1980,¹ and their chequered history is here spelled out in detail in David Freedberg's essay ‘The mycological researches of Federico Cesi and the early Lincei’ (i, pp. 20–45). Along with the drawings of fungi from the Cesi codex are included also (in vol. iii) drawings from the dal Pozzo collection in the Royal Library at Windsor and a set of copies of drawings in the Cesi codex which ended up at Kew. The latter are of special interest, being known to have been seen by Pietro Antonio Micheli, who, like Cesi, though far more extensively and systematically, applied microscopy to the study of fungi.²

The introductory essays in the first of the three volumes are of exceptional quality. Freedberg, well known for his fine book on the natural historical activities of the Lynceans, The Eye of the Lynx,³ sets the Cesi drawings in historical context. He notes that prior to Cesi's investigations only two works exclusively devoted to fungi had been published, Hadrianus Junius's Phalli, ex fungorum genere in Hollandiae sabuletis crescentis descriptio of 1564, a tiny pamphlet with a woodcut on the strikingly phallic dune stinkhorn (now named, after the author, Phallus hadriani), and Carolus Clusius's more substantial and copiously illustrated treatise on Hungarian fungi, Fungorum in Pannoniis observatorum brevis historia of 1601, a work well known to Cesi. Freedberg tells how Cesi and his fellow Lyncean Johannes Heckius pursued their interests in imperfect plants and the secrets of their generation and growth. And he links Cesi's microscopic observations, some of them recorded in his annotations of the drawings, with his Lyncean concern to provide geometrically precise descriptions.

David Pegler, former head of mycology at Kew and a world expert on fungal taxonomy, provides modern specific identifications for the fungi. In his mycologically fascinating essay ‘Species groups, mycological descriptions and nomenclature in the Paris drawings’ (i, pp. 46–58) he surveys the history of classifications of fungi, and explores the ways in which the drawings group together many of the types of fungi recognized today: bracket fungi, coral fungi, cup fungi, puffballs, truffles, stinkhorns, boletes, russulas, amanitas, milk caps and so on. In addition, he carefully examines the terminology of the annotations, noting the difficulties in distinguishing classificatory from descriptive terms.

Though Cesi did not live to write his book on fungi, his interests in them are reflected in his Tabulae phytosophicae (themselves incomplete), published as appendices to editions of the Tesoro Messicano (from 1628).⁴ Freedberg notes that both the Tabulae and the codex show concern with the ordering of plants into related groups. However, he suggests that there is a certain tension between Cesi's commitment to pictures manifest in his commissioning of the fungus drawings and his pursuit in the Tabulae of ‘a logical, non-pictorial means of ordering the world of nature’ (i, p. 41).

In my own reading of the Tabulae phytosophicae (PT), in the form in which they appeared in the 1651 edition augmented by further tables compiled from Cesi's notes,⁵ I have looked for further links with and divergences from the drawings of fungi. Let me start with specifics. Some of the references to fungi in the Tabulae have no evident counterparts in the drawings – for example, Cesi's remarks on the moral analogy between fungi and other parasites, on the one hand, and the kinds of men one should avoid, ‘buffoons, scroungers, and useless manikins’, on the other (PT, p. 931). And there is even an apparent contradiction. In the Tabulae Cesi records sexual differentiation in some plants, claiming to have been the discoverer of its presence in dog's mercury; but he dismisses its presence in fungi as a ‘laughable’ opinion (PT, p. 947). Yet we find drawings of an ‘Agaricus mas’ and an ‘Agaric. Foemina’, both figuring what is nowadays called Fomitopsis officinalis (i, Figures 59, 60). In fact, however, these are figurative uses, the distinction being between the smooth ‘male’ top of the Fomitopsis and its porous ‘female’ underside. However, close specific correlations are to be found. Thus Freedberg notes a typographical box in the Tabulae in which Cesi lists geometrical figures evident in plants, declaring at the end of the list ‘if you seek the use of the compass, go to the fungi’ (PT, p. 910). This fits in nicely with a drawing of the bird's nest fungus, Cyathus striatus, whose annotation refers to its eggs as ‘perfectly circular’ (i, Figure 123). And a whole list of specific correspondences emerges when we turn to the at first glance mysterious contents of the typographical box to be found in the sixth table under the heading ‘Affectiones & Mutationes Internae’ (PT, p. 913). Cesi here starts by stating that he has never observed ‘Metaphytosis’; that is, as an adjacent text makes clear, the complete transformation of a plant from one genus into another. However, he goes on to assert, plants frequently ‘produce from themselves [ex se producunt]’ plants of quite different types, as ‘Mistletoe demonstrates for all to see’. There follows a list of instances involving fungi. From vegetation rotting on the ground fungi burst forth like stamens from flowers. In wooded places withered leaves beget ‘tubers not without exhalation [non sine halitu]’, and sometimes more compact ‘concretions [tophi] not without life’ are found which tirelessly sprout fungi. Moreover, little fungi are produced by putrid fragments of bigger fungi, and he reports that he has seen fungi ‘growing on [others] to the third [stage] [supernatos ad tertium]’; that is, fungi growing on fungi growing on fungi. Cesi concludes by indicating that these matters will be discussed in their place – presumably in his planned treatise on fungi. All this is most beautifully clarified by the drawings. Many of them show the sprouting of stamen-like fungi (e.g. the pin mould shown in i, Figure 35). Figure 114 in the first volume shows a ‘powder fungus [pulverfungus ]’ (the stalked puffball, Tulostoma brumale) puffing a halitus of spores – though it should be added that whilst, as Freedberg notes (i, p. 28), Cesi did with the help of the microscope recognize the spores of ferns, he did not, as far as we can tell, discover the spores of fungi. As for the ‘tophi not without life’ which repeatedly produce fungi, the reference is probably to the hard underground sclerotium of the stone fungus, Polyporus tuberaster (i, Figures 136–8, 157). As explained in the editors' notes on Figure 136 of the first volume, this was known as ‘Lyncurium’, being supposed by some, including Cesi's fellow Lyncean Johannes Faber, to result from the solidification of Lynx urine. These produce edible fungi when watered and were commonly marketed in Rome. Cesi (i, Figure 157) himself notes the edibility; and, in a drawing to appear in a subsequent volume, the sclerotium is annotated by Cesi as a ‘fungus-bearing tuber’. Fungi growing on old fragments of fungi appear, for example, in Figure 203 of the first volume (Nyctalis asterophora on Russula nigricans), which carries a note ‘little-fungus-on-fungus [fungifungulus] on fungal fragments’, and other fungi on fungi include Figure 28 of the first volume (Volvariella surrecta on Lepista nebularis). As for the fungi on fungi on fungi, a fair guess is Figure 445b of the third volume (Collybia racemosa). This is, as the editors note, ‘an interesting and a rare species which grows from a small black sclerotium embedded in the rotting fruit-body of another mushroom’ and whose stem ‘bears numerous lateral outgrowths, each of which terminates in a minute aborted cap’. Cesi's heading of this typographical box with mistletoe as the most obvious case of production of plants of one kind from those of another is, at first sight, somewhat surprising, for the spread of mistletoe seeds by birds had been well known since antiquity (see, e.g., Pliny, Natural History, XVI, xciii). However, Cesi does not actually say that mistletoe is generated from the tree which carries it. Further, he later writes (PT, p. 913), drawing on Virgil (Aeneid, VI, 205–6) of ‘Viscum, quod sua non seminat arbos’ – ‘Mistletoe whose own tree does not sow it’, and this suggests that he knew perfectly well of the spread of mistletoe seeds from tree to tree. So in taking mistletoe as a model Cesi may well be implying that some analogous mode of generation is to be envisaged in the mysterious case of fungi.

What about more general correlations and failures thereof? To start with, there is a significant discrepancy; where the Tabulae outline plans for the quantitative description of plants, their parts and their attributes (see, e.g., PT, pp. 908–10, 918), the only quantification that I have found in the annotations of the drawings is the occasional giving of weights of edible specimens. The Tabulae do indeed engage with the affinities and orderings of plants, and Cesi seems to have envisaged classifications with a somewhat more elaborate hierarchic structure than was usual in the period – thus in Table 3 (p. 907) we find mention not just of the division of genera of plants into varieties, but also of their conjunction into several grades of classes, together with plans for a nomenclature that would reflect the place of a plant in such an ordering. But classification of plants is not the primary concern here. The majority of the tables use, working from left to right, hierarchic divisions of their subject matter.⁶ And, as in Aristotle's History of Animals, Parts of Animals and Generation of Animals, the focus is not on the systematic hierarchic grouping of living beings, but on the differentiation, description and definition of qualities and parts of plants and their functions.⁷ This correlates well with the unprecedented detail in which, sometimes with the aid of the microscope, the drawings represent the anatomical structures of the fungi, their stages of growth, their varieties and their abnormalities.

Historians of science these days tend to be nervous, sometimes obsessively so, of anything that smacks of anachronism. So some may view askance Pegler's modern taxonomic identifications of the fungi and groups of fungi in the Cesi codex. In fact, of course, there is no vicious anachronism here, for there is no attribution to Cesi or his draughtsmen of modern taxonomic concepts or nomenclatural conventions. Indeed, there are important ways in which these diagnoses of fungal species foster a properly historical understanding of Cesi's studies of fungi and other ‘imperfect’ plants. Thus we clearly cannot hope to get to grips with the conventions of representation in the drawings without knowing what species are being depicted. Such identification is also needed if we are to understand what aspects of fungal anatomy, growth and variation are being emphasized in particular drawings and groups of drawings. Similarly, without Pegler's identifications, correlations of the kind attempted above, of the mentions of fungi in Cesi's Tabulae with particular drawings, would be difficult, if not impossible. Moreover, it is only through identification of the fungi that we are able to pick out significant correspondences and divergences between the groupings of fungi in the codex and modern taxonomic groupings. Thus we may note that (as with Aristotle's groupings of animals in his History of Animals) the correspondences with modern taxa occur at varied taxonomic ranks – sometimes with modern genera, as with the amanitas, russulas and milk caps; sometimes with modern families, as with the puffballs; sometimes with yet higher categories, as with the bracket fungi. Further, as observed in the editors' notes, quite a few of the groups are heterogeneous by current taxonomic standards. Thus the wildly various fungi assembled in Figure 28 of the first volume appear to have in common only their fruiting in spring. The fungi in Figure 315 of the second volume seem to share only edibility (the weight of one of the comestibles being given as ‘3 ounces’). Equally diverse in form are the specimens in Figure 394 of the second volume and Figure 477 of the third volume – here the common factor is probably growing in grass as indicated by the heading ‘Palaefungi’ (probably a lapsus for Paleafungi) in the former case and ‘Fenifungi’ in the latter. Then there are instances where there is an evident resemblance, but by modern taxonomic standards only a superficial one – for example, Figures 486 and 467 of the third volume, whose specimens from at least four different modern genera share only an umbilicate form and decurrent gills vaguely reminiscent, as the heading ‘Cardarellae’ indicates, of the chanterelle.

However, the fear of being seduced into anachronism by modern taxonomic diagnoses is not entirely unfounded. To repeat, the identifications are not themselves anachronistic – it is our conceptions of the fungi growing around Rome, not the fungi themselves, that have greatly changed over the past four centuries. But there is a genuine danger that the evident matches of many of the codex groupings with modern taxonomic categories may lead us to attribute anachronistically to Cesi the quest for and/or adumbration of later taxonomic systems. And on this score I am chary of Freedberg's remark about Cesi's anticipation of ‘the Linnean breakthrough’ (i, p. 40). This same issue of prefiguration of systematic taxonomy has occasioned discordant interpretations of Aristotle's natural-historical works. Starting from the evident fact that many of the groups of animals recognized by Aristotle correspond to taxonomic groups recognized today, many have attributed to him a taxonomic enterprise, seeing in his groupings adumbrations of a systematic classification that he failed to carry through. David W. Balme, Pierre Pellegrin and Scott Atran have effectively challenged this view, arguing that the groups of animals recognized by Aristotle are ‘common-sense’ or ‘folk taxonomic’ kinds, which serve for him as starting points in the analysis of parts and functions, not as products of any systematic analysis.⁸ Now there is much room for dispute about the reasons underlying the correspondences between so many of Aristotle's ‘common-sense’ kinds and modern taxonomic categories. Some, Atran for example, have posited universals of human cognitive processing that gave rise to the ‘folk taxonomies’ from which our scientific taxonomy emerged.⁹ Others have placed more emphasis on social, symbolic and utilitarian determinants of ‘folk taxonomies’.¹⁰ In particular, it has been pointed out how living beings special by virtue of their size, abundance, agricultural importance, edibility, ritual or symbolic significance and so on serve as ‘canonical’ types around which folk taxonomies cluster other less significant types.¹¹ Such canonical types appear among the Cesi codex drawings. Thus, as mentioned above, the edible chanterelle provides the model for heterogeneous groups of similarly shaped fungi; the long series of drawings of boletes (i, Figures 160–9, 170–92) seems focused on the equally delicious cep (Boletus edulis), and the delicacy prized by Roman emperors, Caesar's mushroom (Amanita caesarea), looms large along with the field mushroom (Agaricus arvensis) in the array of agarics and amanitas (ii, Figures 315–33). From the perspectives which emphasize cultural determinants the question arises how the passage of Aristotelian common-sense kinds into modern taxonomy has been mediated – whether by a ‘high’ cultural route of reading, teaching and appropriation of Aristotelian texts, or through ‘low’ traditions of practical employment in agriculture, hunting, healing and so on. But none of this calls into question the point at issue here, namely that there are correspondences between many of Aristotle's kinds and modern taxonomic categories, and that this in no way licenses the attribution to Aristotle of any programme of systematic classification of living beings. It seems to me that the kinds of fungi recognized in the Cesi codex are likewise ‘common-sense’ kinds rather than products of any systematic taxonomic procedure, and that, as with Aristotle, it would be misguided, simply on the basis of correspondence between them and our taxonomic categories, to attribute to Cesi a taxonomic enterprise of any of the sorts undertaken by Linnaeus and his successors.

The quality of reproduction of the drawings in these volumes is breathtaking, allowing close reading of the brushwork and of even the faintest silverpoint annotations; and both the introductory essays and the apparatus criticus are exemplary. But, as Freedberg observes at the end of his article, many questions ‘await further analysis’ (i, p. 43). It is, for example, evident at a glance that several different hands, following different conventions of shading and colouring, are at work here, and much painstaking study will be needed to identify (or at least group) them, and to correlate them with the Cesi codex drawings of fungi and other imperfect plants in MS 978, to be published in a later volume of Series B. Moreover, there is little doubt that once all the plant drawings are published it should be possible by searching out the whole range of correlations with the Tabulae to gain substantial insights into the enterprise cut short by Cesi's untimely death. In connection with Cesi's microscopic studies of imperfect plants, Freedberg exclaims, ‘Rarely does a new paradigm in the history of science appear so clearly and decisively beside the evidence for the use of the technology that ushered it in’ (i, p. 39). Yet it is my hunch that, for all Cesi's Lyncean commitment to geometry and microscopy, further study will reveal also a solidly Aristotelian grounding for his project.