Cnidaria- Major Classes
lAnthozoa
l(corals and
lanemones)
lAbout 6500 species
lNo medusa stage
lSome hermaphroditic
lThrive best in presence
lof symbionts-
l(usually heterotrophic
ldinomastigotes)
l
l
l
l
l
lHydrozoa
l(hydras and man-of-war)
lAbout 3100 species      
lMost medusae with velum
lMany with small
lor absent medusa
lPolyps usually bud daughter polyps
lMedusae reproduce sexually
l
l
l
l
l
l
l
l
l
[Image, BIODIDAC, Anth102p.gif Cnidaria Anthozoa Coral heed vista. Showing deep water gorgonians, corals and encrusting sponge. Saba. Description en anglais seulement. Désolé !<br>Coral heed vista. Showing deep water gorgonians, corals and encrusting sponge. Saba.]
                        
[Image, HYDR062P.gif]
Deep water gorgonians,
corals and encrusting sponge.
Obelia- Detail of the bell margin of a
Hydrozoan medusa
(Margulis, Schwartz: 1998)