been made by the academical senate during the preceding collegiate year for a celebration worthy of this rare occasion.
But the jubilation of the anniversary has suddenly turned to deep sadness. We still stand under the dazing influence of the horrible deed by which our noble Empress was torn from us, and we sorrow deeply with our sorely tried august Monarch, to whom we all owe so much, and not least our university.
During the more than five hundred years of its existence, the University of Vienna has passed through no more brilliant epoch than the half century just closing. We are surrounded by speaking witnesses—the building in which we gather for work and for celebration, the grandest palace that was ever built for a university, and a corps of instruction which is scarcely rivaled in the whole world.
Most of the professorships and our university institute were founded during the reign of our present Emperor, including the professorship which has been intrusted to me—exactly a quarter of a century. This was the first regular professorship of plant anatomy and physiology, not only in Austria, but above all, in any university.
In following the time honored requirement of delivering a lecture in the field of one's specialty upon the occasion of entering into the new office, two themes especially present themselves—the development of plant physiology and its present status. Since both subjects have been recently and thoroughly discussed, I have decided to take for the subject of my present address one allied to and scarcely less interesting than those, namely, "The relation of plant physiology to the other sciences."
In the narrow limits of the time allotted to me I can only attempt to sketch in a few strokes the essential features in the reciprocal action between plant physiology on the one side, and on the other side other natural sciences and the social and mental sciences, and to make clear that plant physiology represents not merely a branch for a few specialists, but that it is aided in its advance by the other sciences; that in turn it contributes to advancement in various fields of science and practical life, and, finally, that it reaches out as a many-branched whole into the Universitas literarum.
In my present address I shall use the term "plant physiology" in its broadest sense, as the whole system of teaching relative to the structure, development, and life of plants.
Like all other sciences, plant physiology has developed in response to the demands of life. As physics and chemistry had their basis in the industries, so plant physiology grew by each experience gathered from agriculture, horticulture, and sylviculture. Even if the origin of plant physiology be not historically demonstrable as a result of the demands of practical life, still a portion of our terminology would bear witness to the correctness of the assumption. Expressions like grow, blossom, and graft, designations such as leaf, stem, and root, were not
