of Antoine Laurent De Jussicu. 619 



structure of plants as the state of botany at that time per- 

 mitted. 



The characters of the classes and families illustrate the 

 application and developement of these principles; and the 

 exactness, clearness, and precision of these characters, espe- 

 cially those cf families, allow them still to be considered, if 

 we look back to the period when they were traced, as a 

 model which few authors have equalled, and none sur- 

 passed. 



Finally, the notes at the end of almost every family are, 

 perhaps, the part of the work which principally exhibit the 

 judgment and extensive knowledge of the author. 



It is there, indeed, that he frequently corrects the artificial 

 tendency of a linear series; that he points out the multiplied 

 relations of families among themselves, and acknowledges the 

 doubts which were left in his mind by imperfect observations 

 which he had been unable to verify, or which a deep fore- 

 sight of affinities had given rise to; an impression which often 

 outstrips, so to speak, the actual state of science. How many 

 corrections, introduced later into the natural method, are, in 

 fact, foreseen and pointed out, either in these notes, in the 

 divisions of the sections of families, or even by a word placed 

 at the end of a generic character ! 



This last part of the work, the characters of genera, con- 

 sidered by some superficial authors as a simple labour of 

 compilation, is, in our eyes, not the least remarkable part. 

 Certainly, if the Genera Plantarum of Antoine Laurent De 

 Jussieu had only given, at the end of the characters and the 

 notes upon the families, a list of genera comprised in each of 

 these families, as has since been done by all those who wished 

 to follow his traces, he would have already rendered an im- 

 mense service to science, and rendered the natural method 

 sufficiently evident. Nevertheless, without generic characters, 

 a table of families would then have been merely a work to 

 study and meditate upon : it would not have been a work in 

 common use; the manual, as it might be called, of the botanist; 

 and the natural method would have spread itself much more 

 slowly through the scientific world. 



But, in introducing generic characters, could they be taken 

 by simple compilation from the most esteemed works of the 

 age ? Not in general ; for characters that are simply dis- 

 tinctive, suitable for an artificial system, are frequently no 

 longer suited for a natural method ; or a character, appa- 

 rently useless in the eyes of the systematic author, acquire 

 great importance in those of the student of natural relations. 

 £k> that the characters of the genera have been generally 



