Above, an edible sea urchin, a star fish and a purple spantangus; below, a common octopus and a large cuttlefish. Coloured engraving by W. H. Lizars.

Licence: Public Domain Mark

Credit: Above, an edible sea urchin, a star fish and a purple spantangus; below, a common octopus and a large cuttlefish. Coloured engraving by W. H. Lizars. Wellcome Collection. Source: Wellcome Collection.