visceral ganglion
From ZooTerms (Dictionary of Invertebrate Zoology)
visceral ganglion: 1. (Mollusca: Bivalvia) Ganglion found near the posterior adductor muscle in the posterior viscera.
2. (Mollusca: Gastropoda) Unpaired, median ganglion lying posteriorly and ventrally to the gut; may be fused with other ganglia in advanced forms.
