title: Fine structural changes in the nervous system of the regenerating hydra.
mesh_terms: D000818:Animals; D003063:Cnidaria / Q000033:anatomy & histology*; D066298:In Vitro Techniques; D008854:Microscopy, Electron; D009474:Neurons / Q000166:cytology*; D009489:Neurosecretion; D012038:Regeneration