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In the 1820s, a man named Dr. R. Brandes walked through a meadow on a quest to try and answer a centuries-old question about a mysterious gelatinous substance on the ground known as “star jelly.”

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Over at, you can pick up your very own Microcosmos Microscope.

It comes with four Plan Objectives to ensure the sharpest possible image and using the included phone mount, you can capture images like the ones you’re seeing right now, all of which were recorded on our microscope. Check it out today at In the 1820s, a man named Dr.

R. Brandes walked through a meadow on a quest to try and answer a centuries-old question that had recently begun to spark discussion among his own correspondences. Several of his acquaintances had come across masses of a mysterious gelatinous substance on the ground known as “star jelly,” but no one knew what it could possibly be.

But on the list of possibilities was this: a bacteria called nostoc. Our first discoveries of bacteria are generally credited to Robert Hooke and Antoni van Leeuwenhoek, who wielded their microscopes to explore the invisible worlds embedded in our surroundings and reported back with descriptions of tiny, living things. Their work goes back to the 17th century, relatively recent as far as human endeavors go.

And yet our knowledge of nostoc is much, much older, going back at least 1,600 years, when they featured in Chinese writings describing their use as food. And somehow the bacteria was named “nostoc” in the 16th century, before we knew that bacteria existed. But how?

How could we know about a bacteria before we knew their type existed? How could we see them, let alone eat them or name them or write about them? How could someone like Dr.

Brandes possibly look at a lump of jelly on the ground and think it has anything to do with the little dots we need a microscope to see right now? Well, it’s because nostoc don’t actually live as a single little set of dots on their own. They are part of something larger than them, much much larger.

They exist as a colony, a mass of nostoc held together like these ones. Nostoc are cyanobacteria, and the individual cells are usually shaped like spheres or ovals. These cells are attached to each other, forming the short strands we can see here, which are called trichomes.

But not all of the cells of the nostoc are the same. Life in a colony means that different cells can take on different tasks instead of having to try and accomplish everything at once. Some specialize in reproduction, while others fix nitrogen to help the cells grow.

And some rare cells remain dormant behind thick walls. Their main task is survival, ensuring the nostoc colony can grow from something again should environmental conditions take a turn for the worse. There are several hundred species of Nostoc that we know of, and there is a wide range of sizes to those colonies.

Some are only a few millimeters in diameter, while others— like Nostoc pruniforme— can get up to 22 centimeters in diameter. What holds the trichomes together so they can accumulate into these larger sizes is a gelatinous matrix made of sugars. We’ve actually been staring at this jelly structure the entire time, but it’s hard to see because the cells within it are so still.

The gelatinous shell just melts into the background. But you can see it here. Or rather, you see the jelly shell being poked and prodded at by a creature on the other side of it.

That matrix does more than hold the colony together. It protects it, keeping it safe from solar radiation and other dangers in the environment. And as you may have guessed, the gelatinous structure is the magic behind the mystery mucus piles that people have found lying on the ground.

In fact, the name “nostoc” is a round-about tribute to those squishy lumps. In the 16th century, there was a scientist and alchemist named Aureolus Philippus Theophrastus Bombastus von Hohenheim, though he’s become known by the much shorter “Paracelsus.” Paracelsus was particularly fascinated by folklore, and as he traveled throughout Western Europe, he often looked to talk to peasants and craftsmen and others who might be able to tell him about things like “witch’s jelly,” another phrase used to describe nostoc. Paracelsus was the one who gave the organism the name it’s known by today, drawing on Old English and German words for nostril.

The inspiration for choosing a variation on “nostril” comes, we assume, from the very booger-like appearance of the nostoc, the clumpy green masses they form along the ground. One 17th century writer described nostoc as “excrement blown from the nostrils of some rheumatick planet, falling upon spacious plains, fields and sheep pastures.” The fascination with nostoc came because their lumpy, jelly bodies seemed to come out of nowhere, but were often associated with rain or shooting stars. It’s why their numerous names include things like “spittle of the stars” and “star slime.” We now know why nostoc are capable of such surprising appearances.

It’s not that they come from nowhere. Rather they come from a dry, desiccated state that renders them brittle and dark against the ground, and thus easily missed. They survive these times thanks in part to the sugars surrounding them, which keep them protected from this dry state.

And when it rains, their bodies fill with water, expanding the matrix and thus the colony into something we can see and touch and feel (and yes, sometimes even eat). So when Dr. Brandes investigated the meadow for the masses of gelatinous lumps he found there, nostoc was a distinct possibility.

One apothecary he cited found a Nostoc species on the ground that sounded similar in some ways. But his mass was different. It was a very distinct white color, and it looked more like frog eggs, though not quite.

He did what anyone obsessed with a frustrating identification problem would do and dove into the literature, coming out with a conclusion: what he had found was snail spawn. And who are we to dissuade him? It sounds like our nostoc weren’t responsible for the jelly masses he found.

Which is an altogether anticlimactic ending, we suppose. But we kind of like that. Because over and over again, people find their version of star jelly, and sometimes it is snail spawn.

Sometimes it’s frog spawn that’s been regurgitated by a bird. One time, it even turned out to be waste from a battery treatment plant. And every once in a while, it’s even nostoc.

Because while the microcosmos isn’t the answer to everything, it remains a possibility nonetheless. Thank you for coming on this journey with us as we explore the unseen world that surrounds us. The people on the screen right now, they are our Patreon patrons.

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