43 6 THE HISTORY OF BIOLOGY 



the names and demarcations of which are taken partly from Linn^us's plan 

 for a natural system and partly from the preliminary work of Antoine's 

 uncle Bernard. Some of these orders are, in fact, quite natural, while others 

 are extremely ill arranged, especially in the acotyledon group, in which are 

 included not only Linn^eus's cryptogams, but also the naiads; thus, he in- 

 cludes the ferns among the Cycas, which is placed between the Polypodia 

 and the Equiseta. Jussieu has formed his genera mainly after Tournefort, 

 while his definition of species is reminiscent of Ray rather than of Linnasus. 

 Jussieu, therefore, was not a very original observer, but his service to science 

 lies in the fact that he really worked out a natural system, which he set up 

 in determined opposition to Linn^us's sexual system, and which has, in 

 fact, been the starting-point for all subsequent systematic improvement. 



A far more important observer was Robert Brown (1773-1858), who 

 has been mentioned before as the discoverer of the cell-nucleus. The son of a 

 Scottish clergyman, he studied medicine in Edinburgh and became an army 

 surgeon, but at the same time he applied himself to botany and was appointed 

 botanist to an expedition to Australia, which was led by a Captain Flinders. 

 Brown stayed four years on that continent and brought home large collec- 

 tions; on his return he was made librarian to the Linnean Society and cura- 

 tor at the British Museum. In this position he enjoyed the reputation of 

 being one of the finest botanists of his time; he never published any very 

 important work, however, and his papers were, curiously enough, collected 

 and published in a German translation, done by Nees von Esenbeck, with 

 whom he had but little in common from a scientific point of view. Nor did 

 he work out any system of his own; in his works heuses sometimes Linnasus's, 

 sometimes, and more often, Jussieu's natural system. His service to science 

 lies in the care and keen-sightedness with which he works out and analyses 

 the various orders, or families, as he more frequently terms them:^ his studies 

 of the Compositic, Asclepiadace^, and many other families have been men- 

 tioned as models for the research work of the succeeding age and have con- 

 tributed much towards finding a place for the natural system in the scientific 

 mind. Brown was, moreover, an eminent plant-geographer and made a special 

 study of the distribution of the different families in different climates; in this 

 respect his earlier work on the flora of Australia was unrivalled and attracted 

 the attention of Humboldt, who highly commended it. 



As one of the foremost pioneers of botany should also be mentioned 

 AuGusTiN Pyrame de Candolle. He was born in 1778 at Geneva, where his 

 family had for generations enjoyed a great reputation. At an early age he 

 began to study the natural sciences, which at that time — the age of Bonnet 



^ The term family" as an expression for the natural groups in the vegetable kingdom ap- 

 parently comes from the French botanist Michel Adanson (i 717-1 806), whose attempt, influ- 

 enced by Buffon, to form a natural system for the vegetable kingdom was somewhat of a failure. 



