The immediate result was a composite paper in the _Proceedings of the Geological Society_, by Sir W. E. Logan, Dr. Carpenter, Dr. Hunt, and myself, in which the geology, palæontology, and mineralogy of _Eozoon Canadense_ and its containing rocks were first given to the world.[24] It cannot be wondered at that when geologists and palæontologists were thus required to believe in the existence of organic remains in rocks regarded as altogether Azoic and hopelessly barren of fossils, and to carry back the dawn of life as far before those Cambrian rocks, which were supposed to contain its first traces, as these are before the middle period of the earth's life-history, some hesitation should be felt. Further, the accurate appreciation of the evidence for such a fossil as Eozoon required an amount of knowledge of minerals, of the more humble types of animals, and of the conditions of mineralization of organic remains, possessed by few even of professional geologists. Thus Eozoon has met with some negative scepticism and positive opposition--though the latter has been smaller in amount than might have been anticipated, when we consider the novel and startling character of the facts adduced. The most annoying element in the discussion has consisted in the liability of observers, only partially informed, to confound our specimens with things of very different character, from which we had taken pains to distinguish them. [Footnote 24: In _Quarterly Journal of Geological Society_, vol. xxii.; _Proc. Royal Society_, vol. xv.; _Intellectual Observer_, 1865; _Annals and Magazine of Natural History_, 1874; and other papers and notices.]