In principle, Niklas Bruun’s life has unfolded on its own terms. Initiated into his chosen science at an early age, his ventures into society occurred only in moments of necessity, his nervous system brushing more or less unexpectedly against the real world. A ground-skimming heir to tradition, he displays the innovative nature of those who excavate fundamental betrayals hidden amidst known feats of daring. His writing strikes a solitary tone; during the period in question, the words he writes are meant never to be read.

His journal entries are interspersed with sketches of creatures drawn from nature. There are images of extraordinary flowers, and elliptical chronicles of insects seen in the course of his voyages. At the time, however, there are never any people present in his journal, nothing that would imply any personal relationships.

According to the pens of his critics, the biographical record of Niklas’s mental life appears and disappears like a snake crawling through bushes. Though the thicket covers three continents in all, for a time there is only one. Niklas in Amsterdam, a vagabond, intoxicated on a blend of absinthe and frica (a first reference to the presence of the Tupinambá elixir in Europe). Niklas amidst crevices of cerulean ice, on a trip to collect purple orchids and lichen for a Slavic collector of whom no one had ever heard. Niklas arguing in a half-empty conference room in Madrid; Niklas in Lapland, stretching out a cold-numbed hand to draw; Niklas hurrying out of the Lusitano palace, having refused to discuss anything that wasn’t hyperborean insects.

In his journal, he explains that the plants he draws seem to him to be “a reorganization of human eyes—of the entire human face.” His writings begin to fill with descriptions of strange specimens, ones that future naturalists will be unable to connect to extant vegetal species in any way outside of his journal; in the course of his nocturnal raptures (accompanied by his favorite apéritif, Valdemar, a bit spilled on the page), he comes to believe that he discovered these creatures in his dreams, where he has seen himself moving through underwater caverns, arriving at deranged islands where he is welcomed by mysterious breezes and ground-level clouds not found anywhere else in his writings. “The pools of black gall that await deep in the secret swamps preserve the most extravagant of species: excrescences that suddenly cease their crawling behavior and appear to become a motionless vegetal species, waiting to be ingested providentially, and once made part of the internal environment of their host, they regain their animal form; in this magnificent, fearless kingdom, unimaginable kinships are formed between one species and another . . .” Bruun dissects, composes small portraits; on nights when he is inspired, he works on his ode to Numidae Espora. And then we lose all track of him.

Most likely he is off collecting specimens for Tartare d’Hunval, penetrating the Amazon in a series of ten-day expeditions, returning each time bearing treasure in the form of new species.

Do you think that it’s alive? You would be surprised. The path of these plants runs between life and death; they aren’t of the world of the living, but it can’t be said that they have passed on . . . As you will see, they react furiously to the slightest of stimuli. Their appearance sometimes seems to indicate a putrefactive form, closely allied to fungi and other such beings . . . Their very nature leads them to the limits of their organizationless existence, and from that existential floor they lash out against their enemies. Do you see, do you realize what I’m saying?

His earliest contact with Tartare was related to a series of Crissia pallida specimens, which Tartare had obtained by calling in favors from his network of botanical spies. Tartare claimed that he was simply attracted to the beautiful, simple, black profundity of botany itself, but the tenor of Niklas’s research changed radically after he met Tartare. They were united by their passion for Crissia, and for the study of beings that are born and die outside the realm of all that we think of as real.

Like two ears connected by a wrinkled labellum: the bridge where the insects are lost. As if already condemned to death, they cross it in a state of stupefaction. Libidinous cavern, a paradise created for the depraved, the site induces changes within their bodies.

Tartare set his eyeglasses aside; they were damp with tears. Niklas stayed focused on the magnificent pearlescent creature, which seemed drawn from some epic he’d never read.

When the foot merged with the head, the labellum applied pressure to the sac, which began to fill with succulent aromas, and the axis was inverted: the root was now drawn toward the light of the sun, while a few late-growing bulbs remained near the rock that served as horizon, as watershed. Farther down, the two extremely white and meaty flowers defied architectural norms by growing toward the ground, burrowing down through the air, still bearing the now half-dead insects they had drugged. Sero te amavi, Crissia.

As for Tartare: it had been a malodorous, gelatinous caterpillar, Phobetron pithecium dhunvalica, native to the swamps of Madagascar, that had launched his scientific reputation. He had spent several months admiring them there in the mud; had led them gently into his glass bottles, had sunk into the muck with them, had observed them talking to him in his dreams. He had proposed the first scientific description of the caterpillar, removing it from its originary swamp, binding it to his lineage.

Years later, deep in the Mongolian forest, Tartare had gone blind for several days, which he spent entrapped in the (quite reasonable) belief that he was going to die. For context: in that jungle lives a termite whose mandibles are so powerful that their workings are audible to the human ear. Back when Tartare’s powerful footfall was first heard in the zone, no one had ever heard of Nubia crisallis, and no one could have predicted the means by which the spore made its way into one’s brain. It had entered through his ear, made a pilgrimage through the inner passageways of consciousness much like a memory as described by St. Augustine, and finally reached the cerebral meat of its host. When Tartare returned to Amsterdam, he was unrecognizable.

He claimed that he had been possessed by a series of intuitions that were “completely foreign to the manner in which I had conceived the world,” as he would put it in his new book. Not only had he changed externally; his entire being was imbued with new vigor. He was sure that evolution à la Darwinienne was on its last legs, and in the new classification system that he was designing, certain species fit inside others; they invaded one another, arriving at a matrix of forms that couldn’t be reduced to the issue of mere survival, much less that of generations (an idea he found repugnant). Evolutionary change, he believed, happened much more quickly—within the lifespan of a single individual. Rather than waiting for reproductive cycles to silently select useful features, it occurred via mimesis, and as the result of unexpected contact.

Tartare opened his house there in Amsterdam to a series of scientific spiritualism sessions—trances in which the participants claimed to travel through different geological eras. At these parties, there was a medium who helped the invitees fall into reveries (encouraged by the ingestion of frica) that led them from the dawn of the Devonian to the migrations of the Cretaceous. Niklas would have taken part in these ceremonies.

As Torben Schatts comments in his memoirs, “Everything about [Tartare] denotes a highly refined man irremediably corrupted by his frequenting of actresses, ballerinas, and frica.” In fact, at the time Tartare had decided to content his appetites with nothing but writing and thought. He had promised himself that he would remain celibate until his next book, Orchidaceaen Dithyrambs, was published. In that text he portrays this stretch of his life as follows:

No longer was I that timorous man of yesteryear, the one who stammered the Latin names of the kingdoms under his breath. No longer was I content to hide away amidst my magnificent collection, which was already wholly known to me, and yet through which whole tomes of future natural history could be written. Disdain had given me a second skin, one that was impervious to the digressions of others. It no longer gave me any pleasure merely to crush their meager insights with my perfect erudition; I was ready to destroy their egos altogether with my nomenclaturical euphoria, much the way collapsing towers of stone will squash men like insects.

His Monographie des Termiten was one of the first works to be labeled “speculative botany.” It circulated amongst whispers, accumulating intriguing silences (“culebrin attacks,” in the words of Tartare) and raised eyebrows from those who were capable of raising them. He would later write that snares had already been set with him in mind, and indeed, the judgment of naturalia expert Giovanni Savonarola, creator and destroyer of naturalist reputations, was not long in coming:

The naturalist T. d’Hunval doubtless possesses a talent beyond the ordinary, but he exaggerates his stature as a man of science, and lacks any sense of criteria or rigor . . . and the same can be said of his Monographie. The divine language of Theophrastus as he presented the new field of study at Plato’s academy, and that of Linnaeus when he transformed the field to address secular needs, suffers cruel distortions in the hands of d’Hunval, ones that are frankly quite difficult to tolerate. One is reminded of Friedrich Vischer, who held that there were paintings whose stench one could actually see. Tartare d’Hunval’s book presents us with the horrifying notion that there are scientific compositions whose stinking breath one can actually touch. His naturalist legacy will likely be comparable to the lives of certain insects, best summarized as “a quick trip to the surface before sinking once more into the swamp.”

And then “the abyss, the abominable nothing, phantoms spilling over my name, over me” (Orchidaceaen Dithyrambs, 45). Tartare d’Hunval tries to console himself with thoughts of his destiny as a scientific martyr, and a possible life for his text as an obscure classic. He walks along the Herengracht in Amsterdam feeling like a haloed ghost, intimately protected by his intuitions, his unique visions of caterpillars having slough-bound love affairs with termites and orchids; he talks to himself out loud, tells himself that the only thing that matters is the truth. The aquatic labyrinth of the city leads him from euphoria to melancholy. Much like his caterpillars, he forms a close relationship with muddy water, though these swamps are only infested with humans; he is almost invisible within the walled-in underworld he inhabits. And he can no longer stand the city. In his journal he notes, “Incomparabilis nocta . . . Nictabo splendens,” and draws the profile of a flower that is an insect, its wings outspread.

Numbed by the indifference to his work, Tartare abandons all formal links to the scientific community of his time. He moves to Rio de Janeiro, capital of the Empire of Brazil, later writing that he’d “wanted to be devoured by pure, hard research.” This is the prelude to his most awe-inspiring project, and to the very night that brings us back into contact with Niklas Bruun and the vertigo he feels when in touch with “impure science,” as he calls the dark constellations working their way into the history of science of the Anthropocene.

Upon arriving in Rio de Janeiro, Tartare acquires an old Jesuit church which had been abandoned when the Companhia de Jesus was exiled from Brazil. The vegetation had done its work: the oblong sacristy had become a terrarium, its glass and adobe enclosing pure jungle. Like the tails of gigantic monkeys, vines brushed against the floor where Communion had once been given. The building was a perfect symbol for the challenges of faith in a place where everything up to and including God is eaten by some greater power, and it was precisely what Tartare was looking for. He hired a local man named Zizinho and began construction.

He knocked down the walls of the naves and installed iron staircases connected by hanging walkways that formed a tightening spiral as they climbed. He crowned what was left of the ceiling with a cupola of glass panes and long iron tentacles. To those with a view of Monte da Conceição’s haughty profile, the cupola looked like a gigantic insect, an exquisite tarantula mounted beneath the constellations of the Southern Hemisphere, where there is always more darkness than stars.

Inside his jungle greenhouse, Tartare installed fans to simulate a breeze; the blades combed softly through the layers of plants that grew on the balconies, including worm-infested phosphoric palms from the kingdom of Surinam that sprayed their amber light throughout the tarantula’s interior. Along the walls, a majestic variety of vegetal species “amenable to experimentation” (op. cit.) grew into a labyrinth of leafy waterfalls that replicated themselves via mirrors strategically placed in each cul-de-sac and along dead-end walkways, augmenting the overall effect. Zizinho bought a pig’s stomach, built a bellows to serve as fumigator and pollinator, filled it with cyanide compounds and pollen. The two pet rabbits, Plato and Aristotle, who’d come with Tartare from Holland, began to leave clumps of fur all over, until one day they were found dead. Before burning the bodies, Tartare removed the fat and used it to fertilize his vegetal creatures; they reacted by growing lushly, as if the poisoned tissue of the mammals were the very breath of life.

Each evening around sunset, guests began to arrive. Among the collectors were Bateson from England, the entomologists Arielus Languis and Karl Stu, Kasia Melerina and Baron Tel, Barbosa-Lenz, and Nunzia Lucrezia Damátida, in whose reddish hair was an ornament made of Scorpioniadie scintillans, a translucid scorpion with golden legs. Venetia d’Adda made an entrance: swathes of tulle in black and blue and green, a tall beehive hairdo, a shoulder-length mantilla bearing pieces of jewelry in the shape of fruits, beetles and tiny luminescent worms. Tartare mentioned “Emperor Dom João and the unidentified women from the courtesan world who accompany him, each wearing a hairpiece of dried snakes, each with thin gold chains coiled around her arms.” Zizinho, dressed in his dinner jacket, offers every new arrival a glass overflowing with sparkling salep, a medieval cocktail based in orchid juices, and garnished with a twist of Spilanthes oleracea, an herb that produces an electric-eel tingling on the tongue.

One night the guests were led to what was once the sacristy, rebuilt as an august cabinet room in fine hardwoods. Inside the glass cases were mummified arthropods, several herbolaria, and a map of the stars made of insects, their carapaces diffracting the light. There was the strong smell of formaldehyde, made even stronger by the heat. The guests—resplendent in their tulle gowns, tuxedos, kid-leather shoes—barely fit into the space between the wooden cabinets and the species on display. The smell grew more and more dense, and a woman fell to the floor, unconscious. Tartare exults in his notes: “Only extreme naïveté could lead anyone to think the altar a work of improvisation. And a velvet mantle covers the secret . . . perhaps a glass chest holding some new species?”

As he also notes, “I later learned that he was there . . . blending in with the others, seemingly just another guest.” The identity of this mysterious visitor would not be revealed until sometime later, but it was on that very night, according to Tartare’s diary, that he first heard of Hoichi’s garden. The resulting voyages would lead him deep into the jungle.

Tartare made a small bow toward his guests, and lifted his glass. He held it in the air for several seconds, then looked at Zizinho. Solemnly, Zizinho pulled back the blue velvet mantle, revealing a glass chest with an intricate frame of wood and silver. He opened the lid. Then Tartare bent over with a smile and blew.

Chaos reigned that night. Tartare’s glass chest made prisoners of them all. No one knew if its contents were samples of a new species that no one had ever heard of, or an isolated experiment whose chemical workings they couldn’t begin to imagine. The entire salon went mad. Niklas remembers the event as follows:

Inside were flowers with hooded blooms, like cloistered Franciscan monks in the act of meditation. The humble bouquet contrasted stridently with the preceding orchidacean magic, with the cabinetry, the expectations, and above all with the combined egos of Venetia d’Adda and Tartare d’Hunval. What occurred next is reserved exclusively to the New World memories of those present. As Tartare blew into the chest, a very dense golden powder surged from tiny brown holes in the blossoms. The powder rose up through the gathered guests, navigated through the air overhead in a sinusoid of gold. On the verge of losing consciousness, the guests stretched out their necks to breathe in mouthfuls of this wonder. Then the hallucinations began: it seemed to me that we walked for hours through pastures and along strips of marsh that stretched out like tunnels through the jungle. At certain moments, the color green filled my eyes, I couldn’t make out shapes of any kind, and I felt a taste at once bitter and sweet, a fleck of swamp voyaging through my mouth. But there is one thing I can be sure of. I saw blackish worms take position on the outstretched arm of a young woman, saw them bury themselves in her veins, watched them disappear into pure white foam. She shuddered, opened her eyes wide as the beings mixed with her blood. I tried to approach her, felt that I had to talk to her.

Amidst other spoils of that night, Tartare received a series of offers for the chest—ten thin natives, a number of native children, a medieval castle built just for him in the middle of the Parà jungle. Biting back a faint smile, without saying a word Tartare slipped through the crowd and disappeared through a hidden door, leaving a wake of tulle and glints of light. Zizinho was left with the task of turning away the potential buyers.

Intuiting, perhaps, that the world as he knew it had come to an end, Niklas drew strange translucid plants in his journal, and beneath them he wrote, Hic captabis frigus opacum (here I found the fresh darkness). In the morning, a hungover and half-dressed Tartare came looking for him. The glass chest had disappeared. The plants stared at Niklas, mute.