"Diagram of a typical Hydrozoan polyp. EC., Ectoderm; EN., endoderm; C., the cavity of the gut (coelenteron); G., a reproducive bud; T., a tentacle; H., hypostome or oral cone; M., mouth." -Thomson, 1916

Hydrazoan Polyp

"Diagram of a typical Hydrozoan polyp. EC., Ectoderm; EN., endoderm; C., the cavity of the gut (coelenteron);…