Can anyone explain what this odd thing is (see photo, above)? It was found on a sandy beach along the Mississippi river in Minneapolis in early September. It was solid and it had the consistency of a jellyfish, but appears to have formed along a strand of reed (seen running through the middle) or some other plant-based material. That is a photo of Pectinatella magnified, a member of the Bryozoa - a group commonly known as "moss animals". The gelatinous mass is in fact a colony of dozens of animals, or zoids. A popular name is jelly ball. Most colonies are elongated and they adopt the best shape for clinging to the object to which they adhere. Free-floating colonies tend to be spherical. They are found in stagnant or slow-moving water, so this one in the Mississippi must have floated in from a tributary or a riverside pond. I once encountered a round one as big as a soccer ball. They sometimes sprawl out over a metre or so, resembling a giant amoeba.
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