Among students of animals and plants there is no longer any question as to the =truth= of evolution. That the animals of the present are the altered animals of the past, that the plants of today are the modified plants of yesterday, that civilized man of today is the savage of yesterday and the tree dweller of the day before, is no longer debatable to the mass of biologists. Professor Fish, then of Denison University, Granville, Ohio, not long ago dictated to his class, of which the writer's daughter was a member, the following statement: Organic evolution is the key to all biological thinking of today. It is not a =theory= but a =fact=, because the main facts are true. Man is the off-spring of the lower animals, and the ancestry can be traced back to the simplest forms of animals known. All medical research takes that fact into account. Prof. S. W. Williston, department of paleontology, University of Chicago, says: I know of no biologist, whether of high or low degree, master or tyro, who ventures to suggest a doubt as to the fundamental truths of organic evolution. Prof. William Patten, department of biology and zoology, Dartmouth College, says: Evolution is the accepted doctrine of the natural sciences to the extent that it has long ceased to be a subject of debate in standard scientific journals or in organized conferences of men of science. Prof. Charles B. Davenport, department of experimental evolution, Carnegie Institute, Washington, D. C., says: I do not know of a single modern scientific man who does not believe in evolution. And Prof. Frank R. Lillie, department of embryology, University of Chicago, says: I feel pretty impatient over the statements of certain religious teachers that evolution has collapsed. These statements are sufficiently representative to indicate the attitude toward the theory of evolution of a great section of the scientific world today, including many science teachers in schools founded and endowed by the Church for the giving of Christian education. But it is not true that the theory is universally accepted or even scientifically proved to be a fact. Let a few scientists of at least equal eminence with those quoted above bear their testimony. 2. Testimony =Against= Evolution. But before we quote this testimony it may be well to pause a moment for a little information that may make it more intelligible to us. The so-called proofs of evolution are derived from both the biological and the geological realms of natural science. =a.= We will consider, first, the so-called proofs taken from the =biological= realm.