Comments : Encounters with the largest of the Pacific Northwest jellies are common in Summer months. This is a shot of a medium sized Lion's Mane Jelly with it's bell expanded as it pulsates through the water. Tentacles of the Lion's Mane can often exceed 10 feet in length. I have been stung twice by this species of jellyfish. The sting is very irritating, like nasty bee stings, and lasts for about 6-8 hours.