Classification

1. Class Scyphozoa
   1. Order Stauromedusae--Clown jellies
   2. Order Coronatae--deep water jellies
   3. Order Semaeostomeae--moon jelly and sea nettle
   4. Order Rhizostomeae--Casssiopea
2. Class Cubozoa
   1. Order Cubomedusae--sea wasps
3. Class Hydrozoa
   1. Order Hydroida--most hydrozoans
   2. Order Milleporina--fire corals
   3. Order Stylasterina---hydrocorals
   4. Order Trachylina--trachyline medusae
   5. Order Siphonophora--Physalia
   6. Order Chondrophora--Porpita and Vellea
   7. Order Actinulida--interstial
4. Class Anthozoa
   1. Order Actinaria--most anemones
   2. Order Corallimorpharia--solitary
   3. Order Scleractinia--hard or stony corals
   4. Order Zoanthinaria--Zonanthids
   5. Order Ceriantharia--tube dwelling
   6. Order Ptychodactiaria--cold water anemones
   7. Order Antipatharia--black or stony corals

Labortory Work on Cnidaria

Possible drawings to make from specimens:

• Using x-section slides of hydra and Metridium, compare the nature of the body wall in cnidaria.
• Using the slide of colonial hydroids, show how morphology reflects the division of labor in the hydroids.
• Using preserved specimens, show how the different cnidaria are able to float in the ocean. (Moon jelly, Portugues man-o-war, Vellela)
• Using the slides of nematocysts, show the structures of stinging cells.
• Using moon jellys and sea anemones, show the nature of radial symmetry in the cnidaria.
• Using the slides associated with the life cycle of the jellyfish, show how body shape changes during different stages of the life cycle.
• Using the sectioned pieces of a sea anemone, make a 3-D reconstruction of a sea anemone.

Specimens available for examination:

• Hydra--whole mount, sections
• Colonial hydroids--Obelia and Pennaria
• Physalia (Portuguese man-o-war)
• Vellela (Sailor by the wind)
• Aurelia(moon jelly)--preserved, slides of life cycle
• Metridium (sea anemone)--preserved, slides of body wall
• Various species of coral showing arrangement and size of polyps

Internet Resources

Cnidaria home pages

British Society for Marine Studies

University of California

Freshwater jellyfish page