Depending on the species, the planula either metamorphoses directly into a free-swimming, miniature version of the adult form ( such as many open-ocean scyphozoans ), or navigates through the water until it reaches a hard substrate ( many may prefer specific substrates ) where it anchors and grows into a polyp ( including all anthozoans with a planula stage, many coastal scyphozoans, and some hydrozoans ).
22.
Depending on the species, the planula either metamorphoses directly into a free-swimming, miniature version of the adult form ( such as many open-ocean scyphozoans ), or navigates through the water until it reaches a hard substrate ( many may prefer specific substrates ) where it anchors and grows into a polyp ( including all anthozoans with a planula stage, many coastal scyphozoans, and some hydrozoans ).
