prostomium


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prostomium

(prō-stō′mē-əm)
n. pl. prosto·mia (-mē-ə)
The anterior portion of the head of an annelid worm, situated in front of the mouth.

pro·sto′mi·al (-əl) adj.

prostomium

that part of the head of some annelids and molluscs which lies in front of the mouth.