| If collar cells and spicules are defining characteristics of the Phylum Porifera, then nematocysts define cnidarians. |
| However, actinians, like all coelenterates, capture and digest animal prey with their nematocysts. |
| Only cnidarians manufacture microscopic intracellular stinging capsules, known as nematocysts or cnidae, which give the phylum its name. |
| Casually touching many cnidarians will make it clear how they got their name when their nematocysts eject barbed threads tipped with poison. |
| The tentacles contain harpoon-like stinging capsules called nematocysts that the anemones employ to capture prey and ward off predators. |
| If pain persists, powder and shave the skin to remove any remaining nematocysts. |
