The Portuguese man o' war (Physalia physalis), also known as the Portuguese man-of-war, man-of-war, or bluebottle, is a jelly-like marine invertebrate of the family Physaliidae. Its venomous tentacles can deliver a powerful sting.
blue ring octopus - Produce a strong Nero Toxin called Tetrodotoxin. this Octopus uses as a defensively. It also has a Toxin that is Harleysville to humans and is used on its prey. This little fellow is found in Tide poles in semi warm climates.
"Deep Intellect: Inside the Mind of the Octopus" (article) (via Orion) (November/December The author visits an octopus to explore the evidence that octopi have intelligence, emotions, and individual personalities.