"Anatomy of an Acephalous Mollusc (Mactra): s, stomach; ii, intestine; ag, anterior ganglions; pg, posterior ganglions; mn, muscles; a, anus; h, heart; l, liver; f, foot; sh, shell; ma, mantle; b, branchiae; t, tentacula; r, oral, or respiratory syphon; t, anal syphon." — Chambers, 1881

Mollusc Anatomy

"Anatomy of an Acephalous Mollusc (Mactra): s, stomach; ii, intestine; ag, anterior ganglions; pg, posterior…