Much to his credit, it may be said that a good share of Agassiz's invincible aversion to evolution may be traced to the spirit in which it was taken up by his early associate, Vogt, and, indeed, by most of the German school then and since, which justly offended both his scientific and his religious sense. Agassiz always "thought nobly of the soul," and could in no way approve either materialistic or agnostic opinions. The idealistic turn of his mind was doubtless confirmed in his student days at Munich, whither he and his friend Braun resorted after one session at Heidelberg, and where both devotedly attended the lectures of Schelling--then in his later glory--and of Oken, whose "Natur-Philosophie" was then in the ascendant. Although fascinated and inspired by Oken's _a priori_ biology (built upon morphological ideas which had not yet been established, but had, in part, been rightly divined) the two young naturalists were not carried away by it, probably because they were such keen and conscientious observers, and were kept in close communion with work-a-day nature. As Agassiz intimates, they had to resist "the temptation to impose one's own ideas upon nature, to explain her mysteries by brilliant theories rather than by patient study of the facts as we find them," and that "overbearing confidence in the abstract conceptions of the human mind as applied to the study of nature; although, indeed," he adds, "the young naturalist of that day who did not share in some degree the intellectual stimulus given to scientific pursuits by physio-philosophy would have missed a part of his training." That training was not lost upon Agassiz. Although the adage in his last published article, "A physical fact is as sacred as a moral principle," was well lived up to, yet ideal prepossessions often had much to do with his marshalling of the facts. Another professor at Munich, from whom Agassiz learned much, and had nothing to unlearn, was the anatomist and physiologist Doellinger. He published little, but he seems to have been the founder of modern embryological investigation, and to have initiated his two famous pupils, first Von Baer, and then Agassiz, into at least the rudiments of the doctrine of the correspondence between the stages of the development of the individual animal with that of its rank in the scale of being, and the succession in geological time of the forms and types to which the species belongs: a principle very fertile for scientific zooelogy in the hands of both these naturalists, and one of the foundations of that theory of evolution which the former, we believe, partially accepted, and the other wholly rejected.