Palaeos:		Scyphozoa
Cnidaria		Scyphozoa

Members of this class are large free swimming marine organisms.  The medusa is the dominant phase in the life cycle and the polyp stage is either absent or it is small and gives rise to medusae by asexual budding.  There is a strong four-fold symmetry.

<==o SCYPHOZOA
   |--o STAUROMEDUSAE
   |  |-- Cleistocarpidae
   |  `-- Eleutherocarpidae
   |--o CORONATAE
   |  |-- Atollidae
   |  |-- Atorellidae
   |  |-- Linuchidae
   |  |-- Nausithoidae
   |  |-- Paraphyllinidae
   |  |-- Periphyllidae
   |  `-- Tetraplatidae
   |--o SEMAEOSTOMEAE
   |  |-- Cyaneidae
   |  |-- Pelagiidae
   |  `-- Ulmariidae
   `--o RHIZOSTOMEAE
      |-- Cassiopeidae
      |-- Catostylidae
      |-- Cepheidae
      |-- Lobonematidae
      |-- Lychnorhizidae
      |-- Mastigiidae
      |-- Rhizostomatidae
      |-- Stomolophidae
      |-- Thysanostomatidae
      `-- Versurigidae

Parker, S. P. (ed.), 1982: Synopsis and classification of living organisms. Vols. 1 & 2 --McGrew-Hill Book Company