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Rh show how it is intimately connected with all the leading problems of philosophy and the natural sciences." Beginning with an account of the structure of plants as revealed by the eye and the microscope, he recognizes the labors of Mohl, Nägeli, Payen, and others, and even has the courage to admit that they have damaged his own theory of the genesis of cells. The discussion of the nutritive elements of plants gives him occasion to do justice to Hales, De Saussure, Boussingault, and Liebig, his long-time adversary. Then, from applied botany, he passes to the two sciences which were quite new at the time, of botanical geography and paleontology; and he concludes with a chapter in which the whole subject receives an æsthetical treatment.

Before this work appeared, however, Schleiden, discouraged by the success of the assaults upon his pet theories, had suffered a loss of confidence in himself and of relish for pure botany. His last work in pure science was a note on the fructification of the Rhizocarps, published in 1846; the "Zeitschrift fur wissenschaftliche Botanik" ("Journal of Scientific Botany"), which he, with Nägeli, had founded in 1844, ceased to appear at the same time.

After completing the third edition of the "Grundzüge" in 1850, the failure to modify or improve which in any essential particular emphasizes his loss of relish for the pursuit, Schleiden withdrew almost entirely from the arena of scientific botany. He turned his attention to anthropology; and, finally, in 1862, resigned his chair of botany at Jena, whence he repaired to Dresden. "Still, however, the old halo wavered around his head," and he was called to the University of Dorpat, as Professor of Botany and Anthropology, with the rank of a Russian councilor of state. He was not permitted to stay long there, however; for, being accustomed to express himself too freely on ecclesiastical subjects in his public addresses, he soon raised a strong party against himself, and was obliged to resign his second professorship in 1864. From this time till the end of his life he resided by turns at Dresden, Frankfort-on-the-Main, Wiesbaden, and again at Frankfort, where he died on the 23d of June, 1881. Death surprised him while he was engaged upon a work on the horse, one of three monographs in which he designed to illustrate the influence of natural agents upon civilization, choosing as examples from each of the three kingdoms—salt, the rose, and the horse. The two of these treatises which we possess are models of their kind.

The character of Schleiden may be read in his writings. Ardent and enthusiastic, he never praised or blamed by halves; but, in his most animated polemics, there appears a sincere and disinterested conviction that commands respect. To the end of his life he retained a degree of youthfulness in his thought and style. He had the imagination of a poet, with the scientific spirit to guide it; and instead of being carried away, or letting his readers be carried away, in his flights, he is constantly calling them back to reality and reason. He