Physalia Physalis- Portuguese Man Of War
The Portuguese Man Of War is one of the deadliest jellyfish. One sting from an adult's powerful tentacles and you'll be "swimming with the fishes". Jellyfish do not have skeletal systems. Rather, they are 95% water, 3% salt, and 2% various proteins. A jellyfish is basically a sac within a sac. It is one of Earth's simplest multi-cellular organisms. Nothing in its anatomy even resembles any other organism. A jellyfish's sting release thousands of tiny barbs filled with venom to cause a wound. A jellyfish can even sting while it's dead!