HISTORICAL SKETCH. 15 



In 1852 M. Naudin, a distinguished botanist, expressly stated, in an ad- 

 mirable paper on the Origin of Species {Revue Horlkolc^ p. 102 ; sir.ce 

 partlj' republished in the "Nouvelles Archives du Museum," torn, i., p. 

 171), his belief that species are formed in an analogous manner as varie- 

 ties arc under cultivation ; and the latter process he attributes to man's 

 power of selection. But he does not show how selection acts under Nature. 

 lie believes, like Dean Herbert, that species, when nascent, were more 

 plastic than at present. lie lays weight on what he calls the principle of 

 linality, "puissance mysturieusc, indeterminee; fatalite pour les uns ; pour 

 les autres, volonto providentielle, dont Taction inecssante sur les etres vi- 

 vants determine, ii toutcs les epoqucs de Texistcncc du mondc, la forme, Ic 

 volume, et la durcc do chacun d'cux, en raison dc sa destiuC-e dans I'ordre 

 de choses dont il fait partie. C'est cette puissance qui harmonise chaquc 

 membrc i rensemble en I'appropriant h. la fonction qu'il doit rcmplir dans 

 Torganisme general de la nature, fonction qui est pour lui sa raison 

 d'etre"* 



In 1853 a celebrated geologist. Count Keyscrling {BuV.ei'ni ilc la Soc. 

 Gcohg., 2d Scr., tom. x., p. SSV), suggested that as new diseases, supposed 

 to have been caused by some miasma, have arisen and spread over the 

 world, so at certain periods the germs of existing species may have been 

 cliemically affected by circumambient molecules of a particular nature, and 

 thus have given rise to new forms. 



In this same year, 1853, Dr. SchaalTliauscn published an excellent pam- 

 phlet (" Yerhand. des Naturhist. Yereins dcr Prcus.-!. Ilhcinlands," etc.), in 

 which he maintains the progressive development of organic forms on the 

 earth. lie infers that many species have kept true for long periods, 

 whereas a few become modified. The distinction of species he explains 

 by the destruction of intermediate graduated forms. " Thus living plants 

 and animals are not separated from the extinct by new creations, but are to 

 be regaiilod as their descendants through continued reproduction." 



A well-known French botanist, 51. Lccoq, writes in 185-1 ("Etudes sur 



♦ From rofcrcnccs in Bronn's " Untcrsucluui^xon iibcr die Entwifkchins-'-Oe- 

 pptze " it nppca^^^ that the celebrated botanist and paleontologifit Unser published in 

 ]S5'2 his belief that Bpcclcs undergo development and modillcntion. D'Alton, likc- 

 wi!»c, in Pander and Dalton's? work on Fosfil Slothp, cxprcc-scd, in 1821, a similar 

 belief. Similar views have, as is well known, been uinintained by Okcn in his mys- 

 tical " Niitur-PhiloKophic." From other refcrencci? in Godron's work "Siir VEi- 

 pc^co," it seems that Bory St. Vinecut, Burdacli, Poiret, and Fries, have all admitted 

 that new species are continually bciii:; produced. 



I may add that, of the thirfy-foiir authors named in this lliKtnrical Skcicli, who 

 believe In the modification of species, or nt leasit disbelieve in sepanite acts of 

 creation, twenty-seven have written on special branches of natural history or 

 geology. 



