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Where is the earthworm brain located?

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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.*

The earthworm brain is a bilobed mass of nervous tissue located above the pharynx in the third body segment of the worm. This structure, often referred to as the supraesophageal ganglion, serves as the primary center of the annelid nervous system.12