The polarized PdD electrode undergoes significant morphological changes when exposed to an external electric field. These changes range from minor, e.g. re-orientation and/or separation of weakly connected globules, through forms that result from a combined action of the field as well as that connected with the evolution of gaseous deuterium, to shapes that require substantial energy expenditure. (c) 2005 Elsevier B.V. All rights reserved.