242 



SCIENTIFIC THOUGHT. 



logical view is still more clearly expressed in the 

 further analysis of their regularity and symmetry. The 

 character of the structure is to be found in the ex- 

 istence or absence, in the relative or absolute position, 

 number, size, and shape of the different organs,^ whereas 

 the use or functions of the organs, as well as their 

 other sensible properties,^ are considered to be, not 

 the cause, but the consequence, of their structure, and 

 hence of little importance in the anatomy, and of 

 none in the classification, of plants, whatever may be 

 their value from a physiological point of view. " But 

 symmetry supposes a primitive plan or archetype, and 

 the proofs of symmetry are those of a general order." ^ 

 " The natural classification of organised beings consists 

 in appreciating the modifying circumstances, and in ab- 

 stracting them so as to discover the real symmetrical 

 type of each group." * Here again De Candolle refers ^ to 

 the examples of the crystallographer and the astronomer, 

 who both make abstraction of the disturbing secondary 

 influences in order to arrive at the primitive form and 



que I'avortement ou la degener- 

 escence de certains organes, leur 

 soudures entre eux ou avec d'autres, 

 et leur multiplication d'apres des 

 lois regulieres." 



^ ' Theorie elem.,' p. 147 : " La 

 sym^trie organique se compose d'un 

 certain nombre d'^lemens dont les 

 priucipaux sont : I'existeuce ; la 

 position relative ou absolue ; le 

 nombre relatif ou absolu ; la gran- 

 deur relative ou absolue : la forme ; 

 I'usage ; la duree ; ... les qualites 

 sensibles," &c. 



- Ibid., p. 170 : " L'usage des 

 organes est une consequence de 

 leur structure, et n'en est nulle- 

 ment la cause, comme certains 



ecrivains irr^fl^chis semblent I'in- 

 diquer ; l'usage, quelle que soit son 

 importance dans I'etude j)bysiolo- 

 gique des etres, n'a done eu lui- 

 meme qu'une mediocre importance 

 dans I'anatomie, et ne peut en 

 avoir aucune dans la taxonomie." 

 ... "Ce que je viens de dire de 

 l'usage des organes, s'applique a 

 bien plus forte raison encore a leurs 

 qualites sensibles, qui ne sont que 

 des consequences plus ou moins 

 directes de leur structure," &c. 



3 Ibid., p. 185. •* Ibid., p. 188. 



^ See especially the chapter ' ' De 

 la Symetrie vdgetale " at the end 

 of the ' Organographie, ' vol. ii. p. 

 236 sqq. 



