title: The podial pit--a new structure in the echinoid Diadema antillarum Philippi.
mesh_terms: D000818:Animals; D004447:Echinodermata / Q000166:cytology*; D004847:Epithelial Cells; D006652:Histological Techniques; D008854:Microscopy, Electron; D008928:Mitochondria; D010525:Peripheral Nerves / Q000166:cytology*