THE JUSSIEUS AND THE NATURAL METHOD. 271 



ADRIEN DE JUSSIEU. 



In this sole and last direct inheritor of the name of Jussieuwere early manifested 

 a singularly just and acute discernment, a certain archness of humor, and a senti- 

 ment of profound reapect for his progenitors. To these was added a thorough and 

 very comprehensive instruction. M. Adrien had recognized and resolutely accepted 

 the great weight imposed on him by the celebrity of his ancestry. His works, 

 stamped with merit of a high order, attest even by their small number, due to 

 his scrupulous regard for excellence, a respect for his predecessors and himself. 

 Some of his memoirs * are finished models of that complete and profound study 

 of families which embraces not only all that belongs to the formation of groups, 

 but all that relates to vegetable anatomy, physiology, and geography. His 

 Traite EUmentaire de Botanique supplies the most substantial, precise, and at 

 the same time most elegant survey of the actual state of the science, while his 

 article Taxonomie, in the Dictionnaire universel d'Histoire Naturelle, is the 

 most well-considered and profound disquisition which has been given, in our day, 

 on the important subject of Methods. 



His father, who had relinquished to him his chair at the museum in 1826, had 

 the satisfaction of seeing liim, in 1831, take a place beside him at the Academy. 

 The herborizations, which his great-uncle Bernard and his father had rendered 

 famous, were continued by him. In 1845 he was designated to fill the chair of 

 vegetable organography at the Faculty of Sciences. His pupils will not readily 

 forget with how much skill all available knowledge was condensed in his les- 

 sons. He had been long collecting the materials for a history of botany, and it 

 cannot be too much regretted that his protracted sufferings did not permit him 

 to finish it. Never has an historian been more happily adapted to his task. 

 For such a work he possessed at once clear-sightedness, discrimination, and pro- 

 fundity of knowledge. His colleagues and friends have still in lively re- 

 membrance the vivacity and originality of his conversation, the humorous and 

 graphic turn of his mode of narration. M. Adrien had religiously cuhivated the 

 domestic virtues, which were traditionary in his family, and which contribute so 

 much to the happiness of life. His veneration for his father was almost idola- 

 trous, while his devotion to the two daughters, who survived him, was not less 

 marked by features of the most tender and judicious regard. He died June 29, 

 1853, aged 55 years, having been born December 23, 1797. 



Note to page 23. 



All that ]\I. de Jussieu has produced may be regarded under two chief points 

 of view: character and cJassificalion.. It was with his memoir of 1773 that he 

 opened the study of the former, and in that of 1774 that he laid down the prin- 

 ciples of the latter. 



§ 1. Of characters. — Characters are the signs which indicate the relations of 

 beings. In every organized body, whether animal or vegetable, each part has 

 necessary relations with all the others. We may therefore judge of all by each. 

 And those parts which are thus taken for signs of others, those parts by which 

 we judge of others, are what we name characters. Naturalists had begun by 

 seeking these characters, these signs, almost indifferently in all the parts. It 

 was subsequently recognized that these different parts are very far from having 

 an equal va!ue either in uniting or separating beings. Thence has sprung the 

 valuation of characters, and this valuation has furnished the solution of the pro- 

 blem of method. 



* Especially those on the EuphorbiacecB, (1824,) the RiitacecB, (1825,) the Mcliacece, (1830,) 

 the BT'dp'ffltiacem, (1843,) »S:c., and lastly, his line treatise on Monocotyledinous emhryos, 

 (1839.) I here but indicate his labors ; the time for their complete appreciation has not yet 

 arrived. 



