20 M, Fiourens' Historical Eloge of 



collect for the complete and satisfactory establishment of the 

 truth. 



If it be now inquired what is the peculiar ncierit attached, 

 I may say, to every page of this work, by which it is so stri- 

 kingly distinguished from all those which had previously ap- 

 peared in an investigation so vast, and which had been so 

 often undertaken, it will not be difficult to answer, that this 

 merit consists especially in that continual precision in details, 

 which arranges each part in its true place ; — which, not con- 

 fining itself to the chief results which are rapidly perceived in 

 every genus, neglects none of those truths, in aU the orders, 

 upon which the results are based ; a merit which is altogether 

 essential in a study in which every one of the facts is neces- 

 sary, — in which one cannot be supplied by another, and in 

 which all are nearly of equal difficulty of acquisition, — a merit 

 of the rarest character, and which well explains the profound 

 expression of Buffi>n, that patience, that is to say, constancy 

 in gTeat efforts, is genius. 



M. de Jussieu has been censured, and not without reason, 

 on account of the arrangement of some of his classes being 

 based upon the form of the corolla. This is, in truth, the vul- 

 nerable part of his Method, and he was himself perfectly con- 

 scious of it. " These classes," he remarks, " have this defect, 

 that the allowance of some exceptions is necessary to their ex- 

 istence." He adds, that, viewing the arrangement with the 

 severe glance of science, and not as a matter of convenience, 

 it would be necessary to confine ourselves to the only invari- 

 able character, namely, the lobes of the embryo, and the inser- 

 tion of the stamens. And, in proportion as the number of species 

 has gradually increased, it has more decidedly been ascertained 

 that this last character, taken from the insertion of the sta- 

 mens, is the only one which does not vary, and which, there- 

 fore, ought not to be excluded in the formation of the cha- 

 racter of the classes. In the same way, our continued pro- 

 gx'ess leads also to the establishment of the great division, 

 which is founded upon the lobes of the embryo. M. Desfon- 

 taines, by a singularly beautiful discovery in vegetable ana- 

 tomy, has demonstrated, that the relations drawn from the 

 organs of vegetation, in this division, every where correspond 



