Light micrograph of a branching colony of Zoothamnium sp., a freshwater, ciliate protozoan of the order Peritricha. The colony is sessile and contains

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Light micrograph of a branching colony of Zoothamnium sp., a freshwater, ciliate protozoan of the order Peritricha. The colony is sessile and contains many single-celled individuals, each with a bell-shaped 'head' and a retractable stalk which anchors it to its neighbours. In species of this genus all of the stalk muscles are bound together and the stalks are contracted in unison. Magnification unknown.

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Size: 2480px × 3954px
Photo credit: © DR DAVID PATTERSON/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

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