[i-Cells and reparative morphogenesis in coelenterates]

A historical survey on so called "theory of totipotent interstitial cells (i-cells)" and analysis of modern notion concerning the system of stem i-cells (SSC) in hydra and some other Coelenterata, as well as its peculiar regularity, normal and at various restorative morphogeneses are presented. Morphogenesis and space organization of polyps do not depend on the SSC, just the reverse, the SSC characteristics -- probability of selfrenovation, the TC proportion differentiating in one or other direction -- are determined by the morphogenetic process. In hydra and hydroids a possibility of reversed differentiation of the TC, with a successive change of the differentiation program is demonstrated under certain experimental conditions.