1. 1. Inhibitory innervation of the Helix heart was found to be organized by two multifunctional neurons. Mechanical stimulation of many visceral organs including the heart evokes antidromic action potentials in these cells. 2. 2. Morphological and functional analysis of these neurons showed them to be identical to previously described motoneurons and to the multifunctional interneuron V21. 3. 3. Multifunctional neurons do not interact with one another, they receive direct outputs and inputs from the heart and to the heart. They independently mediate inhibitory cardiocardiac and viscerocardiac reflexes. 4. 4. Due to the presence of several trigger zones in these neurons the reflexes can persist following gangliotomy.