This is one of many of the types of Jellyfish they have at the Monterey Bay Aquarium and one of my favorite ones. It was about the size of your hand and moved quite quickly. It was in a cylinder aquarium which made photographing somewhat difficult. I had to keep the lens of the camera right up against the plexiglass and hope one would swim by far enough away to be in good focus. Note the detail in the dots on this Jellyfish.
Probably a good warning to anyone that might think he would taste good.