To the scrutinising eye of the geologist who visits these tertiary, secondary, and primordial districts, this double progressive series of two kingdoms is to be seen to this day. There was a period upon the Earth when a few islands had but just emerged from the bosom of the warm waters, into an atmosphere surcharged with vapour, when the only living things distinguishing this inorganic kingdom were long floating filaments held in suspension in the waves. Seaweed and sea-wrack were the first forms of vegetation. On the rocks, live creatures for which one has no name. There, sponges swell out. Here, a tree of coral lifts up itself. Further on, the Medusæ detach themselves and float like balls of jelly. Are these animals? Are these plants? Science does not answer. They are animal-plants, zoophites. But life is not limited to these forms. There are creatures not less primitive, and as simple, which typify a special species. These are the annelides, worms, fish in the form of a simple tube, creatures without eyes, ears, blood, nerves, will, a vegetative species, yet endowed with the power of _motion_. Later on rudimentary organs of sight and of locomotion appeared, and life became less elemental. Then fishes and amphibious creatures came into existence. The animal kingdom began to form itself. [Sidenote: Formation of the animal kingdom.] What would have been the result if the first creature had never quitted its rock? If these primitive elements of terrestrial life had remained stationary at the point of their formation, and if, for any cause whatever, the faculty of locomotion had never had a beginning? The consequence would have been, that in place of the system of terrestrial vitality being manifested in two different directions, viz., in the world of plants and the world of animals, it would have continued manifesting itself solely in the first direction, with the result that there would have been but one kingdom instead of two, and the creative progress would have operated in that kingdom as it operated in the animal kingdom. It would not have been arrested at the formation of sensitives, superior plants which are already gifted with a veritable nervous system; nor would it have stopped at the formation of flowers, which are already bordering on ours in their organic functions; but, continuing its ascension, would have produced, in the vegetable kingdom, that which has already been produced in the animal kingdom. As it is, many vegetables feel and act; here would have been vegetables feeling and making themselves understood. The Earth would not have been on that account deprived of the human species. Only mankind, instead of being gifted with locomotion as it is, would have been fixed by the feet. Such is the state of the annular world in which I lived fifteen centuries ago in the heart of the Milky Way.