Fun and Games

New Jersey Jellyfish and Test your knowledge with a game!

By Lauren Wink

Welcome to the Jellyfish Treehouse!

Be sure to play "Don't Get Stung by the Jellyfish"
(play after you learn about jellyfish below)

Common name: Jellyfish   Scientific name: Scyphozoa

Click on an image to view larger version & data in a new window
Click on an image to view larger version & data in a new window


Jellyfish are part of the Animal Kingdom. They are invertebrates, which means they do not have a backbone. They are in the phylum Cnidaria and most jellyfish are in the class Scyphozoa. Jellyfish are also referred to as Medusas.

What do jellyfish look like?

Many people think of jellyfish as little creatures in the ocean that sting you. Not all jellyfish are harmful. The stinger on most jellyfish cannot even be seen. Hydromedusae, clear jellyfish,  don't sting you when you touch them. Jellyfish have a gastric cavity, this means that they only have one opening as a mouth and an anus. Jellyfish do not have a brain, heart, gills, kidney or liver. Many jellyfish have tentacles which they use for feeling and grasping. They use these tentacles to grasp other creatures or plants (fish, plankton) to eat as food.

Harmful Jellyfish

The Red Mane, also known as the Lion Mane Jellyfish, Cyanea capillata, is extremely dangerous. The tentacles of the Lion Mane jellyfish can grow up to 200 feet long and the actual body of the jellyfish can grow up to eight feet! Pelagia noctiluca or Purple Jellyfish are also very harmful and should definitely be avoided. The Purple Jellyfish can grow up to 40 centimeters across. It has five tentacles surrounding its mouth, that are used for feeding. Both the Purple Jellyfish and the Lion Mane Jellyfish are found in New Jersey.

Common Name: Moon Jelly     Scientific Name: Aurelia aurita

Click on an image to view larger version & data in a new window
Click on an image to view larger version & data in a new window

Left image © 2005 Dave and Debra Wrobel. Right image courtesy NOAA Photo Library

Moon Jellys are also found in New Jersey. Moon Jellys are part of the Semaeostomeae order, Ulmaridae family, Aurelia genus, and A. aurita species. It's binomial name is Aurelia aurita. The tentacles of a moon jelly are attatched under the "umbrella shaped body." Moon Jelly are harmless to humans.

 Life Cycle

Click on an image to view larger version & data in a new window
Click on an image to view larger version & data in a new window

© 2005 California Academy of Sciences

The life cycle of a jellyfish is shown in the picture above. The male jellyfish releases a sperm into the water and this matches up with an egg released by a female jellyfish.  The sperm and the egg are formed in the gonad. When the sperm and the egg fuse, they make a fertilized egg. A larva or Planula then forms and this attaches to a rock or another object on the bottom of the water and this is known as a polyp. The polyp folds over on itself creating a "colony of polyps" or Strobila. Each of the polyps in the colony detach and are medusae or adult jellyfish. Most jellyfish live less then a year.

Time to test you jellyfish knowledge!

Game: Don't Get Stung By the Jellyfish!



Answer Key for Trivia Cards:


  1. Cnidarians
  2. Medusa
  3. high tides
  4. On most jellyfish you can not see the stinger
  5. Both sexual and asexual
  6. Lion Mane or Red Mane
  7. up to 200ft
  8. eight feet
  9. Clear jellyfish
  10. false
  11. true, extremely dangerous
  12. true
  13. Gonad
  14. Planula
  15. Rock or another object on the bottom of the water
  16. false
  17. Gastric cavity
  18. One opening for both the mouth and the anus

What do you think?

My fellow classmate, Josh, read my webpage and played the game. He felt that the game really helped him review what he learned from the site and that it was very educational.

Sarah said, "I think it's a very convenient way to study. Everything is on one page and is easily accesible. It's much easier then opening both notes and text."


Jacobson, Morris K., and David R. Franz. Wonders of Jellyfish. 1st ed. New York: Dodd, Mead, 1978.

Douglas, Lloyd G. Jellyfish. 1st ed. : Children's Press, 2005.

King, David C. Jellyfish. 1st ed. : Benchmark Books, 2005.

George, Twig C. The Life of Jellyfish. 1st ed. : Lerner Publishing Group, 2001.

Learning Information

About This Page

Author: jellyNJ1
Classroom Project: Don't Get stung by the Jellyfish
Rutgers Preparatory School
Somerset, NJ USA

License: Tree of Life & Partners uses only - Version 1.0

Correspondence regarding this page should be directed to , Rutgers Preparatory School

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