Atono,y of Mollusca

adductor muscle ammonoids ancestors animal anus aperture Aplacophora bivalves Bivalvia body buccal burrowing calcareous Cambrian carnivores Caudofoveata cephalopods Charonia chitons cilia clade cladistic cladogram clams coiled conchiferan Cyrtosoma developed Devonian digestive gland diverse dorsal early elongated esophagus evolved exhalent chamber extinct feeders food particles foot forms fossil freshwater mussel ganglia gastropods gills Glycymeris groove habitats Helcionella Helcionellids hinge holed infaunal inhalent water intestine invertebrates Kissonerga land snails large number larval Latouchella layer limpets Linnaeus Linsley and Kier living lobes Macluritids mantle cavity marine Melanopsis Mesozoic molluscs Monoplacophora morphology mouth muscular musculature Myogenesis Nautilus nephridia nerve occur Ordovician organs oysters pair Paleozoic pallial Paragastropoda pedal periostracum phylum planispiral Polyplacophora posterior primitive prosobranchs pulmonates radula represented retractor Rostroconchia Rostroconchs samples Scaphopoda sediment shell siphon soft Solenogastres species squid stomach style sac substrate surface suture taxa teeth tentacles Tergomya topshells Tryblidiida umbo Unionoida valves ventral visceral mass whorl