In connection with Ferenczi's view (expressed in his Versuch einer Genitaltheorie) that the intrauterine life represents in some sense a recapitulation of a previous water-existence led by the ancestors of certain present land animals, attention is drawn to some experiments with salamanders showing that deprivation of water tends to bring about a longer period of intrauterine life. As a result of this prolongation of the first stage of life the larvæ become provided with lungs ready for a land existence from birth onwards, whereas under normal conditions a considerable time is spent in the water before the development of lungs enables the young animals to take to the land.