This 1963 science educational chart demonstrates the inner and outer workings of Hydra, which you may remember from your early science classroom days when you first learned to use a microscope. According to some quick research, biologists are especially interested in hydras due to their regenerative ability and that they do not undergo senescence (aging). This wonderful chart is laminated and is in amazingly near pristine condition, retaining its original vibrant colors of this beautifully illustrated plant life. Chart has metal casing on top and bottom and two rings at the top - ready for hanging. Measures 3' wide x 4' tall and ships rolled in a sturdy mailing tube.