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Polyplacophora & Cephalopoda --Polyplacophora-- The phylum Polyplacophora, meaning “many plates”, contains chitons, marine mollusks with oval bodies bearing eight dorsal plates. Chitons live only in marine habitats and are commonly found in rocky areas of the intertidal zone along the coasts of almost every sea. They are stationary and cling to their rocky surfaces. Chitons are supported by eight calcareous plates called valves. Depending on the species, these plates may be small or large, covering most …

…near the funnel until copulation. Before copulation squids may swim acrobatically around each other and then they will position themselves head to head. The male wraps his tentacles around the female and uses his hectocotylus arm to reach into his funnel and pull out spermatophores. The male then places the spermatophores into the female’s mantle where sperm are released. The female pulls out egg sacs after fertilization and places them in between rock crevices.