No wonder that Darwin should say in conclusion, 'One is astonished at the amount of creative force, if such an expression may be used, displayed on these small, barren, and rocky islands; and still more so at its diverse, yet analogous, action on points so near each other.' Here again, in real earnest, the young observer trembles visibly on the very verge of natural selection. In the 'Origin of Species' he makes full use, more than once, of the remarkable facts he observed with so much interest in these tiny isolated oceanic specks of the American galaxy. From the Galapagos the 'Beagle' steered a straight course for Tahiti, and Darwin then beheld with his own eyes the exquisite beauty of the Polynesian Islands. Thence they sailed for New Zealand, the most truly insular large mass of land in the whole world, supplied accordingly with a fauna and flora of most surprising meagreness and poverty of species. In the woods, our observer noted very few birds, and he remarks with astonishment that so big an island--as large as Great Britain--should not possess a single living indigenous mammal, save a solitary rat of doubtful origin. Australia and Tasmania, with their antiquated and stranded marsupial inhabitants, almost completed the round trip. Keeling Island next afforded a basis for the future famous observations upon coral reefs; and thence by Mauritius, St. Helena, Ascension, Bahia, Pernambuco, and the beautiful Azores, the 'Beagle' made her way home by slow stages to England, which she reached in safety on October the 2nd, 1836. What an ideal education for the future reconstructor of biological science! He had now all his problems cut and dried, ready to his hand, and he had nothing important left to do--except to sit down quietly in his study, and proceed to solve them. Observation and collection had given him one half the subject-matter of the 'Origin of Species;' reflection and Malthus were to give him the other half. Never had great mind a nobler chance; never, again, had noble chance a great mind better adapted by nature and heredity to make the most of it. The man was not wanting to the opportunity, nor was the opportunity wanting to the man. Organism and environment fell together into perfect harmony; and so, by a lucky combination of circumstances, the secret of the ages was finally wrung from not unwilling nature by the far-seeing and industrious volunteer naturalist of the 'Beagle' expedition.