Studies on the dynamics of morphogenesis and inheritance in experimental reproduction. II. Physiological dominance of anterior over posterior regions in the regulation of Planaria dorotocephala

It has long been recognized by the botanists that the apical region is physiologically dominant over other regions to a greater or less extent in higher plants.In Tubularia (Child, '07) and various-perhaps all other-hydroids the hydranth region is dominant over more proxinial regions so far as they are not beyond the limit of effectiveness for the given conditions.In the present and following papers data will be presented which establish, I think, beyond a doubt that in Planaria dorotocephala a relation