The Source of cells in regeneration and growth

The source of cells which give rise to the new tissues and organs in regeneration has been described in a large number of animals. In Section I a review of the literature dealing with this subject in a number of groups of animals - Amphibia, Reptiles, Mammals, Oligochaete and Polyehaete Annelids, Nemerteans, Sponges and Coelenterates - will be made. The source of the cells which proliferate new cells in the growth of certain tissues - Epidermis, Retina, Muscle, Notochord, Cartilage and Gut, as well as intravascular multiplication of Erythrocytes - will be dealt with in Section II. This will embrace the original observations of the present author. The literature available on this topic is scanty and will not be treated separately but incorporated into the text of the observations - with due credit to the authors concerned. In Section III a few notes on ""The Form of Epithelial Cells During Division", "Cellular Dedifferentiation1" and a Summary will be given