30'2 Historical Notice of 



lowers ; merely a passing glimpse had been obtained of it ; its nature 

 was not yet demonstrated. 



The Genera of 1789 had, on the contrary, a speedy influence on 

 the direction of botanical studies. This influence was not indeed 

 immediate, for the public attention was then turned to events of 

 high importance altogether foreign to science. But at the end of 

 a few years the work had come almost into general use throughout 

 France in public teaching, not only in the instructions of the facul- 

 ties and the Garden of Plants at Paris, but also in the majority of 

 the central schools, those foci of general and varied instruction which 

 were too speedily destroyed. 



Of the botanical works in ordinary use, the Flore Francaise of 

 Lamarck and of Decandolle, as well as many local floras, were ar- 

 ranged according to this method, and made it more generally known ; 

 and scarcely twenty years had elapsed, when an eminent botanist 

 declared himself one of its most devoted champions, and contributed 

 materially to bring it to perfection. Since that time it has spread 

 over Europe, and it may be even said the whole world. Its supe- 

 riority over artificial methods is generally acknowledged, and the 

 latter are now admitted only in their proper character, namely, as 

 more or less convenient keys for opening a way to the nomenclature 

 of vegetables. 



We may add, with Cuvier, that the influence of the Genera Plan- 

 tarum is not confined to botany. Every branch of natural history, 

 and zoology in particular, have derived benefit from the principles 

 which guided Jussieu, and which he has so well explained in his 

 admirable introduction ; and we are inclined to think that Cuvier, 

 in expressing this opinion, founded it on his own experience, and 

 that the principles alluded to regulated him in the changes he in- 

 troduced into the zoological system. To exercise in a gradual and 

 durable manner so positive and generally acknowledged an influence 

 on the progress of science, a work must necessarily unite two different 

 kinds of merit ; general ideas of a varied, important, and novel cha- 

 racter, and as perfect an application as possible of these principles 

 in all their details. These, in fact, are the qualities we find united 

 in the Genera of Antoine-Laurent de Jussieu. The introduction, 

 written in the most perspicuous and elegant Latin ever employed 

 on scientific subjects, presents an exposition not only of the fun- 

 damental principles of the natural method, but as perfect a view 

 of the structure of vegetables as the existing state of botany per- 

 mitted. 



The characters of the classes and families afford an opportunity 



4 



