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How do transverse rings give annelids their name?

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annelid *The structure of polychaetes.* (Left) Free-moving polychaetes. (A) *Neanthes,* (B) *Nereis.* (Right) Tube-dwelling (sedentary) polychaetes. (C) *Amphitrite,* (D) *Sabella.*

Annelids derive their name from the Latin word annellus, which means "small ring". These invertebrate animals are characterized by bodies divided into segments by transverse rings, also known as annulations.12