In the February of the year in which Haeckel was born (1834), twenty-eight years before the point we have arrived at, Charles Darwin was on a scientific expedition to South America. There is a romantic element in the earlier story of this journey. The naked Fuegians had stolen a boat from an English Government ship that was engaged in making geographical measurements, towards the close of the twenties, on the wild coast of Tierra del Fuego. FitzRoy, the captain, arrested a few of the natives, brought them on board as hostages, and in the end took them with him to England. They were to be instructed in morality and Christianity and then taken back to their people, in order to introduce these elements of civilisation, for the advantage of shipwrecked sailors or distressed travellers who might fall in with them. We feel a breath of the spirit of Rousseau in it. As a fact nothing came of the device. The good Fuegians were clothed and improved by civilised folk for a year or two, returned home, immediately abandoned their trousers and their Christianity, and remained naked savages. But the bringing home of these hostages led, in the early thirties, to a new expedition of FitzRoy to Tierra del Fuego. The Government directed him to draw up further charts, and he looked about for a man of science to accompany him. The man proved to be Charles Darwin, then in his twenty-second year. The son of a prosperous provincial physician, he had begun to study medicine without much success, and was transferred to theology, only to find after three years of study that he was as little fitted to become a country clergyman as a country doctor. He had an unconquerable love of scientific investigation. He collected all kinds of things, and desired to travel, without any very clear idea of his destiny. A chance introduction came to the young man as a godsend, and he joined FitzRoy’s expedition to South America. Once more, it was this journey that made him “Darwin,” the mighty intellectual force in the nineteenth century. Darwin found an idea in South America. You have to examine it very closely to appreciate it clearly. Let us recapitulate very briefly the hundred years of zoology and botany that had gone before.