that time the question of the origin of species was considered transcendental, not a subject for inquiry. It seems proper now to mention the influence of the "Principles of Geology," by Sir Charles Lyell, published in 1832. The doctrine of Catastrophes, or the supposition that at different times all life had been destroyed by the convulsions through which the earth had passed, and that a new life had been created from time to time, was supported by the high authority of Cuvier. Lyell, in the work just mentioned, put forward the view that these catastrophes had been only local, and that they had been brought about by the same forces that are now modifying the earth; that life has always existed,—new forms appearing, old forms passing away; that disturbances have taken place at different times in different places, just as at present we have earthquakes, volcanic eruptions, etc. This view is at present accepted by most Geologists, very few believing any longer in the Cuvierian theory of the "Revolutions of the Globe." The effect of the "Principles of Geology" on the progress of the Development theory was very great, since one of the objections to it, of life having been often extinct all over the globe, was therein shown to be groundless. Although the doctrine of Development was opposed by naturalists, nevertheless from time to time it was advocated, as in 1837 by Dean Herbert, in 1844 by the anonymous author of the Vestiges of Creation, in 1846 by D'Omalius d'Halloy, in 1852 by Naudin, in 1855 by the Rev. Baden Powell and by Büchner, and from 1852 to 1858 by Mr. Herbert Spencer, Remembering the vast discoveries that had been made since the days of Lamarck in Zoology, Botany, Geology, that the study of Embryology had been raised to a science, that of the Geographical Distribution of plants and animals more was known, etc., let us now call attention to the famous book on the Origin of Species, by Mr. Darwin. The two great merits of this work are its bringing together in a con-
