raphy, when pursued in a purely biological spirit, let us employ an imaginary problem. Figure to yourselves a continent absolutely unknown in any of its physical features of earth, climate or configuration; let us imagine that from such an unknown continent all the animals and all the plants could be brought into a vast museum, the only condition being that the latitude and longitude of each specimen should be precisely recorded, and let us further imagine a vast number of investigators of the most thorough zoological and botanical training and with a due share of scientific imagination, set to work on this collection. Such an army of investigators would soon begin to restore the geography of this unknown continent, its fresh, brackish and salt-water confines, its seas, rivers and lakes, its snow peaks, its glaciers, its forests, uplands, plains, meadows and swamps; also even the cosmic relations of this unknown continent, the amount and duration of sunshine as well as something of the chemical constitution of the atmosphere and of the rivers and seas. Such a restoration or series of restorations would be possible only because of the wonderful fitness or adaptation of plants and animals to their environment, for it is not too much to say that they mirror their environment.
At the historic period commemorated by this great exposition of St. Louis when Napoleon concluded to sell half a continent to strengthen his armies, it is true that such a solution of a physical problem by biological analysis might have been conceived by the pupils of Buffon, by Napoleon's great contemporaries Cuvier, Lamarck or St. Hilaire, but the solution itself would not have been possible. It has been rendered possible only by the wonderful advance in the understanding of the adaptation of the living to the lifeless forces of the planet. Finally, it is obvious in such a projection of the physical from the purely biological that the degree of accuracy reached will represent the present state of the science and the extent of its approach toward the final goal of being an exact or complete science. The illustrative figure need not be changed when the words paleozoology and paleobotany are substituted for zoology and botany. We still read with equal clearness the physical or environmental changes of past times in the biological mirror, a mirror often unburnished and incomplete, owing to the interruptions in the paleontological records, but constantly becoming more polished as our knowledge of life and its all pervading relations to the non-life becomes more extensive and more profound.
Such an achievement as the reconstruction of a continent would be impossible in paleontology pursued as geology or as a logical subdivision of geology. The importance of the services which paleontology may render geology as time-keeper of the rocks, or which geology may render paleontology, are so familiar that we need not stop to enumerate them. Te emphasize the relation I have elsewhere suggested the phrase, Non
