I publish these essays at the present time for a particular reason connected with the present situation; a reason which I should like briefly to emphasise and make clear. Though most of the conclusions, especially towards the end, are conceived with reference to recent events, the actual bulk of preliminary notes about the science of Eugenics were written before the war. It was a time when this theme was the topic of the hour; when eugenic babies (not visibly very distinguishable from other babies) sprawled all over the illustrated papers.