Enterocoelous

Enterocoelous development is the stage of embryological development of deuterostomes in which the coelom forms. The stage starts with the gastrula; as the archenteron forms, pockets of migrating cells also form, creating another layer between the endoderm and ectoderm, the mesoderm. These pockets gradually expand to form the coelom.

(See Schizocoelous for coelom development of protostomes.)