Martius on the Life and Labours of DeCandolle. 17 



noble disinterestedness, sacrificed in this cause a gi'eat portion of 

 his estate. 



Equally formidable are the internal obstacles attendant upon 

 the examination of vast collections of plants. The characteristics 

 of the genera according to the natural method are made to rest 

 upon organic peculiarities, which scarcely required a notice in the 

 Linnsean system ; such for example as the internal structure of 

 the ovary, the ovule, and the seeds. The use of the microscope, 

 neglected by Linnaeus, is now become quite indispensable. The 

 distinguishing marks of species are founded on numerous and 

 often very minute diiferences, which require a close examination 

 of all the parts. To make out a diagnosis, the description must 

 now be more circumstantial than formerly, when a few words were 

 sufficient to discriminate between related species. Linnseus's 

 ^ Systema Plantarum,' in the Reichardt edition of 1779, describes 

 seven species of the genus Eugenia, and only thirteen of Myrtus. 

 DeCandolle, in the year 1828, has 194 of the former genus and 

 145 of the latter, of which he forms two divisions. It is obvious 

 to every one that this immense increase of the labour of the sy- 

 stematic describer must weigh heavily upon each separate species. 

 To this must be added, finally, the necessity of regarding each 

 plant no longer merely as a prepared, or, as it were, crystallized 

 production of nature, as was done by Linnseus, but as a living and 

 acting self-developing being ; a view which has been elicited by 

 the doctrines of morphology, and which cannot now be wholly 

 excluded from merely descriptive treatises. 



DeCandolle began his great work in the year 1818, in an ex- 

 tended form, under the title of ^ Regni Vegetabilis Systema Natu- 

 rale.^ Two volumes had already appeared, when he perceived that 

 so immense a field laughed to scorn the limits of human life ; he 

 therefore adopted a condensed form, and published seven volumes 

 between the years 1824 and 1838. With an enthusiasm which 

 has perhaps never inspired any other botanist, he devoted the 

 greater part of the day to this gigantic task. Still he was not able 

 to go through the whole extent of the vegetable kingdom in this 

 manner. The work was interrupted by his death in the middle 

 of the eighth volume ; and a great portion of the so-called Mono- 

 petalous plants, as well as the classes of Monocotyledones and Aco- 

 tyledones, are yet untouched. 



DeCandolle appears peculiarly great in the accurate compre- 

 hension of the characters both of genera and species. In the de- 

 scription of distinctive marks, he not unfrequently departs from 

 the terminology of the Linnsean school. Whilst he at times de- 

 scribes a given object with admirable art, conveying the most 

 lively image to the mind, his expressions occasionally fail of this 

 distinctness. No one who can realize the greatness of the task 



Ann, ^ Mag, N, Hist, Fo/.xii. C 



