Young Mark spends a busy, noisy day helping out at Gram's seaside hot dog stand. After the last customer is served and the grill is scrubbed to a silvery shine, Mark sails off with Gram for a promised surprise, and finds a nighttime sea full of shimmering moonjellies. The scientific name for the creatures in this story is Ctenophore, they are also called comb jellies or sea gooseberries. In New England they are most plentiful in the late summer. They are not true jellyfish because they don't have stinging cells or tentacles. Moonjellies are harmless. 25th Anniversary Edition.