HISTORICAL SKETCH. 



works he upholds the doctrine that all species, including man, are 

 descended from other species. He first did the eminent service of 

 arousing attention to the probability of all change in the organic, as 

 well as in the inorganic world, being the result of law, and not of 

 miraculous interposition. Lamarck seems to have been chiefly led 

 to his conclusion on the gradual change of species, by the difficulty 

 of distinguishing species and varieties, by the almost perfect gradation 

 of forms in certain groups, and by the analogy of domestic produc- 

 tions. AVith respect to the means of modification, he attributed 

 something to the direct action of the physical conditions of life, 

 something to the crossing of already existing forms, and much to us«? 

 and disuse, that is, to the effects of habit. To this latter agency ha 

 seems to attribute all the beautiful adaptations in nature ; — such as 

 the long neck of the giraffe for browsing on the branches of trees. 

 But he likewise believed in a law of progressive development; an' I 

 as all the forms of life thus tend to progress, in order to account for 

 the existence at the present day of simple productions, he maintains 

 that such forms are now spontaneously generated.* 



Geoffroy Saint Hilaire, as is stated in his 'Life,' written by his 

 son, suspected, as early as 1795, that what we call species are 

 various degenerations of the same type. It was not until 1828 

 that he published his conviction that the same forms have not been 

 perpetuated since the origin of all things. Geoffroy seems to have 

 relied chiefly on the conditions of life, or the " monde ambiant " as 

 the cause of change. He was cautious in drawing conclusions, and 

 did not believe that existing species are now undergoing modifica- 

 tion ; and, as his son adds, " C'est done un probleme a reserver 

 entierement a l'avenir, suppose menie que l'avenir doive avoir prise 

 sur lui." 



* I have taken the date of the first publication of Lamarck from Isid. 

 Geoffroy Saint Hilaire's (' Hist. Nat. Ge'ne'rale,' torn. ii. p. 405, 1859) excel- 

 lent history of opinion on this subject. In this work a full account is given 

 of Button's conclusions on the same subject. It is curious how largely my 

 grandfather, Dr. Erasmus Darwin, anticipated the views and erroneous 

 grounds of opinion of Lamarck in his ' Zoonomia ' (vol. i. pp. 500-510), 

 published in 1794. According to Isid. Geoffroy there is no doubt that 

 Goethe was an extreme partisan of similar views, as shown in the Intro- 

 duction to a work written in 1794 and 1795, b"it not published till long 

 afterwards : he has pointedly remarked (' Goethe als Naturforscher,' von 

 Dr. Karl Meding, s. 34) that the future question fcr naturalists will be how, 

 for instance, cattle got their horns, and not for what they are used. It is 

 rather a singular instance of the manner in which similar views arise at 

 about the same time, that Goethe in Germany, Dr. Darwin in England, 

 and Geoffroy Saint Hilaire (as we sha'l immediately see) in France, came 

 to the same conclusion on the origin of species, in the years 1794-5. 



