Specific Inhibition of Regeneration in Clymenella Torquata

Evidence is presented suggesting the presence of specific head-and tailinhibitors, and of even more specific dorsal-ventral intra-organ tail-inhibitors.2. The tail-inhibitor is shown to be distributed along a posterior-to-anterior gradient.3. Another substance, a "somatic factor," is postulated as existing along an anterior-to-posterior gradient.4. The electrophoretic mobilities of the head-and tail-inhibitors at sea water pH are demonstrated.5. The possibility of bioelectric control of the movements and concentrations of growth- and pattern-specific substances is briefly considered.