SPECIAL BOTANY 



Special Botany is concerned with the special morphology and 

 physiology of plants. While it is the province of general botany to 

 investigate the structure and vital processes of the whole vegetable 

 kingdom, it is the task of special botany to interpret the structure 

 and vital processes of its separate divisions. The aim of general 

 morphology is to determine the phylogenetic dei^ivation of the 

 external and internal segmentation of plants, and to refer their 

 numerous structural peculiarities to the primitive forms from which 

 they have arisen. The purpose of special morphology, on the other 

 hand, is to trace the development which has been reached in the 

 different divisions of the plant kingdom, to understand the form of 

 individual plants, and to trace the connection between one form and 

 another. Thus the methods of special morphology are also phylo- 

 genetic, and furnish the basis for a NATURAL system of classifica- 

 tion of vegetable organisms, based upon their actual relationships. 

 Such a system must necessarily be very imperfect, as it is not 

 possible to determine, directly, the phylogenetic connection of different 

 plants, but only to infer their relationships indirectly from morpho- 

 logical comparisons. 



Such a natural system, founded on the actual relationshijD existing 

 between different jDlants, stands in direct opposition to the artificial 

 system, to which has never been attributed more than a practical 

 value in grouping the plants in such a manner that they could easily 

 be determined and classified. Of all the earlier artificial systems, 

 the sexual system proposed by Linnaeus in the year 17.35 is the 

 only one which need be considered. 



LiNNiEUS, in establishing his classification, ntilised characteristics which referred 

 exclusively to the sexual oi'gans, and on this basis distinguished twenty-four classes 

 of plants. In the last or twenty-fourth class he included all such plants as were 

 devoid of any visible sexual organs, and termed them collectively Cryptogams. 

 Of the Cryptogams there were at that time but comjjaratively few forms known, 

 and the complicated methods of reproduction of this now large class were absolutely 

 unknown. In contrast to the Cryptogams, the other twenty-three classes were dis- 

 tinguished as Phanerogams or plants whose flowers with their sexual organs could 

 be easily seen. Linn^us divided the Phanerogams, according to the distribution 

 of the sexes in their flowers, into such as possessed hermaphrodite flowers (Classes 



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