Anthomedusae from Haeckel's classic textbook Art forms in Nature published in 1899

A regular light micrograph of Eleutheria

Expression of Hox-like genes in the medusa (jellyfish) stage of the hydrozoan Eleutheria. Cnox-1 is expressed in the "cnidoblast channel" of the manubrium (gene expression visualised using a green fluorescent probe)

Expression of Hox-like genes in the medusa (jellyfish) stage of the hydrozoan Eleutheria. Cnox-3 is expressed around the mouth (gene expression visualised using a purple pigment)

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