Use your mouse to magnify this hydrozoan medusa (type of jellyfish, but not a "true" jellyfish). It has 4 clusters of tentacle with stinging cells called cnidocytes. There is a small sensory structure at the base of each tentacle cluster for light and equilibrium sensing. The gut is the orange structure at the center and if you look closely you can see it extending throughout the body in thin gastrovascular canals. Surrounding the gut is an ovary with white circular eggs. Click the thumbnail images below to see more images of jellyfish and other cnidarians with one thing in common - they sting their prey!