BOTANY. 



By Prof. William G. Farlow. 



During the year 1881 there has been great activity in the depart- 

 ment of vegetable physiology, arising from the appearance of Darwin's 

 Poicer of Movement in Plants, which, although announced in 1880, was 

 not in reality known to the botanical public until 1881, but which has 

 since its appearance been the subject of numerous important communi- 

 cations and discussions; from the discussions on the nature and action 

 of chlorophyl excited by the publication of Pringsheim's researches on 

 chlorophyl; and from the discussions of Schimper, Naegeli, and Meyer 

 on the mode of growth and formation of starch grains, of Pfeffer, Boehm, 

 and others on the cause of the movement of water in plants, and other 

 questions of primary importance in the economy of plants. 



Publications on vegetable anatomy, except so far as it relates to the 

 structure of the vegetable cell itself, have not been very numerous. In 

 cryptogams there may be said to have existed a mania for the forma- 

 tion of systems of classification. The paper of De Bary on 8aprolegniew 

 and Peronosporece, and the papers of Brefeld, figure among the more 

 important works on the development of fungi, while descriptive works 

 on both algse and fungi have been numerous and important. On the 

 higher cryptogams and phaenogams the works published have been less 

 numerous and of less magnitude than usual, although several notable 

 contributions have been made. In this country considerable activity 

 has been shown, and the proportion of original observations made con- 

 cerning cross-fertilization and other physiological and etiological ques- 

 tions seems fortunately to be increasing. 



VEGETABLE ANATOMY AND PHYSIOLOGY. 



Decidedly the most important work to be credited to this year, al- 

 though, as before said, it in reality appeared at the end of 1880, is Dar- 

 win's admirable work on the Poicer of Movement in Plants, with regard 

 to which a detailed account is unnecessary in this connection, inasmuch 

 as the work is so generally and popularly known. Accepting the phe- 

 nomenon of circumnutation as a fact, nothing could apparently be more 

 satisfactory than the explanation given of the action of the difterent 

 parts of the embryo in germination, and of the motions of leaves and 

 other parts of plants. When, however, the question is asked, what is 

 the cause of circumnutation, it will be noticed that all vegetable physi- 



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