Jellyfish is a guidebook that appears in the comic Split Decision.
It is a large blue book with a picture of pink jellyfish on the front and back covers, and a picture of a green field on the front cover. The book's title is written on the book's front cover and spine.
The book contains information about various species of jellyfish, including the Pink-Tufted Finger Stinger, which the book describes as a rare breed that is nicknamed "The Shy Lady of the Sea."
Role in comic
SpongeBob consults the guide when he wants to know more about the Pink-Tufted Finger Stinger.