ON A. LAURENT DE JUSSIEU, 5T 



and for the same reason, because they alike neglected to ob- 

 serve the relative importance of different characters. More 

 yet may be said, which is, that taking all botanists from the 

 time of Gessner downwards, those who were most correct in 

 their views, and who seemed, as it were, to stumble on some 

 fragments of a Natural Arrangement, tiiese were all following, 

 unknown to themselves, the views afforded by the relative value 

 of characters. Still farther, there are natural families all 

 ready made; as the Grasses, the Composita: and Umhelliferce: — 

 let any one study these families, and he will find that every 

 character by which any individual plant varies, is only sub- 

 ordinate and secondary ; the primitive, important and essential 

 character pervades the whole family. 



Order, gradation and subordination exist therefore in 

 characters, and the main difficulty is to classify these charac- 

 ters. Now this was quite a novel aspect in science. Bernard 

 de Jussieu, who had introduced the principle of the relative 

 value of characters when classifying plants, had not sufficiently 

 combined the theory and practice of this principle, but Lau- 

 rent did so; he showed its aim, he consummated the great 

 chanfje which his uncle had commenced, and exhibited the 

 philosophy of this system. 



At the time when M. de Jussieu was writing these two 

 Memoirs, which contain the germs of all that he finally 

 accomplished, his uncle and Linnjeus were both alive. These 

 great Naturalists died soon after, Bernard in 1777, and Lin- 

 naeus the following year. From thenceforth the first place 

 in Botany was vacant, and every one perceived that it was 

 M. de Jussieu who should fill it; he himself must have been 

 sensible of it too, and I accordingly find, in one of his letters, 

 the following remarkable words, " There are circumstances 

 of which a man ought to avail himself, and I should be to 

 blame if I neglected one which is now offered me. In 

 three months, we have lost the three greatest botanists in 

 Europe, M. de Haller in Switzerland, M. Linnaeus in Sweden, 

 and my uncle at Paris. How honourable it would be to suc- 

 ceed them, and thus secure to France the precedence which 



Journ. o/Bof. Vol. IIL No, 18. Nov. 1840. i 



