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A banded tube from the late Silurian/early Devonian. The bands are difficult to see on this specimen, as an opaque carbonaceous coating conceals much of the tube. Bands are just visible in places on the left half of the image – click on the image for a larger view. Scale bar: 20 μmCuticle of Cosmochlaina, retrieved from the Burgsvik beds by acid maceration. Cells about 12 μm in diameter.
