matchless traditions of its glorious past. What the Wartburg was to Martin Luther, what Weimar has been to the foremost heroes of German literature, what Jena herself has been during three hundred years to a vast number of illustrious investigators, that will the tried and tested Jena of to-day undoubtedly continue to be to the modern doctrine of evolution, as to every other doctrine which asks free development; a stronghold of free thought, free investigation, and free doctrine.

JENA, June 24th, 1878.

ERNST HAECKEL.

FREEDOM IN SCIENCE AND TEACHING.

CHAPTER I.

DEVELOPMENT AND CREATION.

NOTHING is more helpful for the understanding of scientific controversies, or for the clearing of confused conceptions, than a contrasted statement, as defined and clear as possible, of the simplest leading propositions of the contending doctrines. Hence it is highly favourable to the victory of our modern doctrine of evolution that its chief problem, the question as to the origin of species, is being more and more pressed by these opposite alternatives: Either all organisms are naturally evolved, and must in that case be all descended from the simplest common parent-forms-or: That is not the case, and the distinct species of organisms have originated independently of each other, and in that case can only have been created in a supernatural way, by a miracle. Natural evolution, or supernatural creation