Bell

Differences in the bell margin can be useful to distinguish orders of medusae. For example, the Semaeostomeae, in contrast to the Rhizostomeae, have tentacles on the bell margin. The form of the bell margin also can differ considerably between species within orders and lower taxonomic levels (Family, Genus, Species). The number of lappets and the number of lobes, for example, are often used to distinguish among species within a genus. Some examples of this variation are shown below. The rhopalia, which are obvious features of the bell margin, are discussed in more detail above.