"The lion’s mane jellyfish (Cyanea capillata) is the largest known species of jellyfish. Its range is confined to cold, boreal waters of theArctic, northern Atlantic, and northern Pacific Oceans, seldom found farther south than 42°N latitude. Similar jellyfish, which may be the same species, are known to inhabit seas near Australia and New Zealand. The largest recorded specimen found, washed up on the shore ofMassachusetts Bay in 1870, had a bell (body) with a diameter of 7 feet 6 inches (2.29 m) and tentacles 120 feet (37 m) long. Lion’s mane jellyfish have been observed below 42°N latitude for some time—specifically in the larger bays of the east coast of the United States.”
By the way, this picture (below) is a fake. Some ongoing talk can be found here.