INCEPTION OF THE GENEKA PLANTAEUM 19 



beyond the powers of any one man to undertake. About 1857 

 they found that they had this idea in common. Thereupon 

 plans and guiding ideas were fully discussed: Work began with 

 the sixties, and by 1862 the first part of Vol. I: appeared. This 

 was completed in 1865: Of Vol. II. the first half appeared 

 in 1873, the second in 1876 ; of Vol. Ill:, similarly in 1880 and 

 1883, the work, as long as it was arduous, thus covering nearly 

 a quarter of a century. 



The aim of the work was not so much, like that of so many 

 others, to produce a complete new system, as to lay the foun- 

 dation for this by the accurate definition of the smaller groups. 

 Systematic botany was taken not as an end in itself, but as 

 a means of illustrating the laws of evolution and the dispersal 

 of species, and the relation of physical changes to these laws. 

 The authors set out to give a revised definition of every genus of 

 flowering plants, a view of its constituent species, geographical 

 distribution and synonymy, with references and notes. * It 

 is difficult,' Hooker once wrote to Bentham, ' to keep one's 

 wits sharp in revising such pregnant matters.' The especial 

 value lay in the fact of a personal re-examination of thousands 

 of specimens, living or dead, whenever practicable, for between 

 them the authors had an extent of knowledge and a command 

 of materials never previously attained. At the same time as 

 he analysed his materials for the Genera, Bentham took the 

 opportunity to discuss fully some of the more important orders 

 in the Linnean Society's Journal. 



The general framework upon which Bentham and Hooker 

 built their work was not a new one. It was adapted, with 

 advantageous modifications, from the system set forth by De 

 Candolle. This they chose as the most satisfactory of the many 

 with which the path of botanical science had been strewn 

 with increasing frequency from 1789 to 1857. Botanists 

 were constantly striving after a natural system of classi- 

 fication as opposed to the artificial, non-natural system of 

 Linnaeus, which long held the field by reason of its utility in 

 identifying plants. 



A natural system, said Bay, was not to bring together dis- 

 similar species, nor to separate those which are really allied. 



