gation. The performances of both men were at first extremely weak and contradicted one another; a lively dispute on the nature of cells, fibres, and vessels grew up during the succeeding years, and many German botanists soon took part in it; life was once more infused into the whole subject, especially when the academy of Göttingen in 1804 offered a prize for the best essay on the disputed points, for which Link, Rudolphi and Treviranus contended, while Bernhardi occupied himself with private researches into the nature of vessels in plants. It was not much that was attained in this way; men began once more from the beginning, and after 130 years Malpighi and Grew were still the authorities to whom everybody appealed. Yet the questions now discussed were in the main different from the old ones; Malpighi, Grew and Leeuwenhoek had chiefly set themselves the task of studying the different tissues in their mutual connection; the moderns were chiefly concerned to get a clearer understanding of the more delicate construction of the various tissues themselves, to know what was the true account of cell-structure in parenchymatous tissue, and the real nature of vessels and fibres. That very slow progress was made at first in this direction was due partly to the imperfectness of the microscope, and still more to very unskilful preparations, to the influence of various prejudices, and to too slight exertion of the mind. But a comprehensive work by the younger Moldenhawer in 1812 was a considerable step in advance. It is marked by careful and suitable preparation of the objects, and by critical examination of what was observed by the writer himself and of what had been written by others; in fact it is a fresh commencement of a strict scientific treatment of phytotomy. Hugo von Mohl continued Moldenhawer's work after 1828, and Meyen was a contemporary and a zealous student of phytotomy; but the period in the study of vegetable anatomy which reaches to 1840 may be said to have been brought to a conclusion chiefly by von Mohl's contributions. Weak as the beginnings were at the
