CLASS HYDROZOA 

 Portuguese Mon-of-War Velella 



CLASS ANTHOZOA 

 Sea Anemone 



CLASS ANTHOZOA 

 Sea Fan Sea Pen 



CLASS ANTHOZOA 



Astrongia 



Fig. 23.1. Representatives of the three classes of coelenterates, all are greatly 

 reduced but not to the same scale. These or nearly related species live in both At- 

 lantic and Pacific coastal waters. Class Hydrozoa, hydroids: Eudendrium, colony 

 of polyps, 5 inches high; Gonionemus, medusa, % inch in diameter, cosmopolitan; 

 Physalia, Portuguese man-of-war, colony of polyps beneath a gas float, 10 inches 

 long, tentacles up to 50 feet long when fully extended, float 6 to 8 inches in diame- 

 ter; Velella, the "little sail" of the California coast. Class Scyphozoa, jellyfishes: 

 Aurelia. Class Anthozoa, sea anemones and corals: Metridium, brown anemone, 

 length to 4 inches; Astrangia, white coral, colonies of 5 to 30 individuals, 10 inches 

 diameter, Florida to Cape Cod; Gorgonia, sea fan, a colony of horny corals, in 

 warm waters on coral reefs; sea pen, a colony of fleshy polyps, warm coastal waters. 



467 



