202 DARWINIANA. 



equally have to be verified inferentially. If we still 

 hold to the idea of Linnaeus, and of Agassiz, that ex- 

 isting species were created independently and essen- 

 tially all at once at the beginning of the present era, 

 we could not better the propositions of Linnaeus and 

 of Jussieu. If, on the other hand, the time has come 

 in which we may accept, with De Candolle, their suc- 

 cessive origination, at the commencement of the pres- 

 ent era or before, and even by derivation from other 

 forms, then the " inprincipio" of Linnaeus will refer 

 to that time, whenever it was, and his proposition be 

 as sound and wise as ever. 



In his " Geographic Botanique " (ii., 1C68-1077) De 

 Candolle discusses this subject at length, and in the 

 same interest. Remarking that of the two great facts 

 of species, viz., likeness among tJie individuals, and 

 genealogical connection, zoologists have generally pre- 

 ferred the latter, 1 while botanists have been divided in 

 opinion, he pronounces for the former as the essen- 

 tial thing, in the following argumentative statement : 



" Quant a moi, j'ai etd conduit, dans ma definition de 1'espcce, 

 4 mettre ddcidement la resserablance au-dessus de caracteres de 

 succession. Ce n'est pas seulement a cause des circonstances 

 propres au regne vegdtal, dont je m'occupe exclusivement ; ce 

 n'est pas non plus afin de sort ir ma ddfinition des theories et de 

 la rendre le plus possible utilo aux naturalistes descriptenrs et 

 nomenehitcurs, c'est anssi par un motif philosophique. En toute 

 chose il faut aller au fond des questions, quand on le peut. Or, 

 ponrquoi la reproduction est-elle possible, habituelle, fdconde 

 indofiniment, ontro des etres organises quo nous dirons de la 



1 Particularly citing Flourens : " La resscmblance n'est qu'une con- 

 dition secomlaire ; la condition essentielle est la descendance : ce n'est 

 pas la ressemblance, c'est la succession des individus, qui fait 



