614 Historical Notice 



Thus, although Bernard De Jussieu has not made known 

 the rules which directed him in his researches respecting the 

 natural method, we cannot doubt that he had recognised two 

 of those principles of this method, which are admitted in the 

 present day as the most essential and the least subject to ex- 

 ception ; namely, that the differences in the structure of the 

 embryo furnish the characters of the first order ; and the diffe- 

 rent modes of insertion of the parts of the flower, the charac- 

 ters of the second order. But, when we examine the different 

 catalogues which preceded the planting of the Trianon garden, 

 we see that it was not at the first essay he arrived at this 

 result, and how he has successively completed both the asso- 

 ciation of genera into families, and the distribution of these 

 families. 



Such was the condition of botany, as it respects the natural 

 method, when Antoine Laurent De Jussieu, born at Lyons in 

 1748, came to Paris, in 1765, to finish his medical and scien- 

 tific studies, under the direction of his uncle, Bernard De 

 Jussieu. The first years of his stay in this city were solely ap- 

 propriated to his studies, which he terminated in 1 770 by his 

 thesis for a degree of doctor in medicine, containing internal 

 evidence of the direction which he had given to his labours ; 

 and the genius which had guided him since his entry upon a 

 scientific career, was evident from the style and subject of this 

 thesis, which was entitled, An (Economiam Animalem inter et 

 Vegetalem Analogia P and it is, in fact, a concise exposition, 

 written with elegance and precision, of all that was most posi- 

 tively known at that period upon the structure and the 

 functions of vegetables, and a comparison of these with the 

 phenomena of animal life. 



The manner in which this question is treated was evidently 

 a brilliant debut for a youth only twenty-two years of age ; and, 

 asLimonnier, then professor of botany, was unable, on account 

 of the engagements devolving upon him from his situation of 

 first physician to the king, to fulfil his duties at the Jardin 

 Royal, Bernard De Jussieu proposed the young Antoine Lau- 

 rent De Jussieu to supply his place, which was agreed to ; and 

 he then applied himself with renewed ardour to study the 

 branch of science which he found himself called upon to teach. 



The paper upon the Ranunculi, which he read, in 1773, to 

 the Academy of the Sciences, proves how quickly he had 

 profited by his studies, and that he was thoroughly imbued 

 with the excellent principles which, as we before pointed out, 

 had evidently directed Bernard De Jussieu in his attempts at 

 natural classification. 



In this first memoir, which gained for him admission into 



