title: The rectum of "Modiolus" demissus (Dillwyn) (Bivalvia: Mytilidae): a clue to solving a troubled taxonomy.
mesh_terms: D000818:Animals; D049872:Bivalvia / Q000033:anatomy & histology / Q000145:classification*; D009132:Muscles / Q000033:anatomy & histology; D012007:Rectum / Q000033:anatomy & histology