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HOFMEISTER, WILHELM FRIEDRICH BENEDIC...
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See also:HOFMEISTER, WILHELM See also:FRIEDRICH See also:BENEDICT (1824-1877) , See also:German botanist, was See also:born at See also:Leipzig on the 18th of May 1824. He came of a See also:family engaged in See also:trade, and after being educated at the Realschule of Leipzig he entered business as a See also:music-dealer. Much of his botanical See also:work was done while he was so employed, till in 1863 he was nominated, without intermediate See also:academic steps, to the See also:chair in See also:Heidelberg; thence he was transferred in 1872 to See also:Tubingen, in See also:succession to H. von See also:Mohl. His first work was on the See also:distribution of the Coniferae in the See also:Himalaya, but his See also:attention was very soon devoted to studying the sexuality and origin of the embryo of Phanerogams. His contributions on this subject extended from 1847 till 186o, and they finally settled the question of the origin of the embryo from an ovum, as against the prevalent See also:pollen-See also:tube theory nof M. J. See also:Schleiden, for he showed that the pollen-tube does not itself produce the embryo, but only stimulates the ovum already See also:present in the ovule. He soon turned his attention to the See also:embryology of Bryophytes and Pteridophytes, and gave continuous accounts of the germination of the spores and fertilization in Pilularia, Salvinia, Selaginella. Some of the See also:main facts of the See also:life of ferns and mosses were already known; these, together with his own wider observations, were worked into that See also:great generai pronouncement published in 1851 under the See also:title, Vergleichende Untersuchungen der Keimung, Entfaltung and Fruchtbildung koherer Kryptogamen and der Samenbildung der Coniferen. This work will always stand in the first See also:rank of botanical books. It antedated the Origin of See also:Species by eight years, but contained facts and comparisons which could only become intelligible on some theory of descent. The See also:plan of life-See also:story See also:common to them all, involving two alternating generations, was demonstrated for Liverworts, Mosses, Ferns, Equiseta, Rhizocarps, Lycopodiaceae, and even See also:Gymnosperms, with a completeness and certainty which must still surprise those who know the botanical literature of the author's See also:time. The conclusions of Hofmeister remain in their broad outlines unshaken, but rather strengthened by later-acquired details. In the See also:light of the theory of descent the common plan of life-See also:history in See also:plants apparently so diverse as those named acquires a See also:special significance; but it is one of the remarkable features of this great work that the writer himself does not theorize—with an unerring insight he points out his comparisons and states his homologies, but does not indulge in explanatory surmises. It is the typical work of an heroic See also:age of plant-See also:morphology. From 1857 till 1862 Hofmeister wrote occasionally on physiological subjects, such as the ascent of See also:sap, and curvatures of growing parts, but it was in morphology that he found his natural See also:sphere. In 1861, in See also:conjunction with other botanists, a plan was See also:drawn up of a handbook of physiological See also:botany, of which Hofmeister was to be editor. Though the See also:original See also:scheme was never completed, the editor himself contributed two notable parts, See also:Die Lehre von der Pflanzenzelle (1867) and Allgemeine Morplaologie der Gewdchse (1868). The former gives an excellent See also:summary of the structure and relations of the See also:vegetable See also:cell as then known, but it did not greatly modify current views. The latter was notable for its refutation of the See also:spiral theory of See also:leaf arrangement in plants, founded by C. F. Schimper and A. Braun. Hofmeister transferred the discussion from the See also:mere study of mature See also:form to the observation of the development of the parts, and substituted for the " spiral tendency " a See also:mechanical theory based upon the observed fact that new branchings appear over the widest gaps which exist between next older branchings of like nature. With this important work Hofmeister's See also:period of active See also:production closed; he See also:fell into See also:ill-See also:health, and retired from his academic duties some time before his See also:death at Lindenau, near Leipzig, on the 12th of See also:January 1877. (F. O. Additional information and CommentsThere are no comments yet for this article.
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