population of Russia will be at the end of the century. But Gruber's estimate is altogether fallacious. German births have fallen, roughly speaking, about one per thousand of the population, every year since the beginning of the century, and it would be equally reasonable to estimate that if they continue to fall at the present rate (which we cannot, of course, anticipate) births will altogether have ceased in Germany long before the end of the century. The German birth-rate reached its climax forty years ago (1871-1880) with 40.7 per 1,000; in 1906 it was 34 per 1,000; in 1909, 31 per 1,000; in 1912, 28 per 1,000; in an almost measurable period of time, in all probability long before the end of the century, it will have reached the same low level as that of France, when there will be little difference between the "invulnerability" of France and of Germany, a consummation which, for the world's sake, is far more devoutly to be wished than that anticipated by Gruber. We have to remember, moreover, that this tendency is by no means, as we are sometimes tempted to suppose, a sign of degeneration or of decay; but, on the contrary, a sign of progress. When we survey broadly that course of zoological evolution of which we are pleased to regard Man as the final outcome, we note that on the whole the mighty stream has become the less productive as it has advanced. We note the same of the various lines taken separately. We note, also, that intelligence and all the qualities we admire have usually been most marked in the less prolific species. Progress, roughly speaking, has proved incompatible with high fertility. And the reason is not far to seek. If the creature produced is more evolved, it is more complex and more highly organised, and that means the need for much time and much energy. To attain this, the offspring must be few and widely spaced; it cannot be attained at all under conditions that are highly destructive. The humble herring, which evokes the despairing envy of our human apostles of fertility, is largely composed of spawn, and produces a vast number of offspring, of which few reach maturity. The higher mammals spend their lives in the production of a small number of offspring, most of whom survive. Thus, even before Man began, we see a fundamental principle established, and the relationship between the birth-rate and the death-rate in working order. All progressive evolution may be regarded as a mechanism for concentrating an ever greater amount of energy in the production of ever fewer and ever more splendid individuals. Nature is perpetually striving to replace the crude ideal of quantity by the higher ideal of quality.