300 



SCIENTIFIC THOUGHT. 



who occupies a unique position in the history of natural 

 science. He introduced the principle and aspect of 

 development into the midst of those studies which, under 

 the important but one-sided influence of Cuvier and his 

 school, were in danger of being confined within the 

 limits of morphology and comparative anatomy. Through 

 a long series of most important embryological investiga- 

 tions, conducted during the years 181 9-1837, he demon- 



science from tlie spell under which 

 it was kept for a long time in the 

 West of Europe by the great 

 authority of Cuvier. Geograph- 

 ically also, von Baer's activity was 

 centered in Kiinigsberg (where he 

 was one of a brilliant company who 

 made the University celebrated) and 

 St Petersburg. Though a great 

 admirer of Cuvier, whose biography 

 he wrote, and an adherent of the 

 doctrine of animal types, which he 

 independently arrived at, he intro- 

 duced three distinct lines of re- 

 search into his scientific labours, to 

 all three of which Cuvier was either 

 foreign or distinctly averse — viz., 

 microscopic research, study of em- 

 bryological development, and the 

 philosophical spirit of the " Natur- 

 philosophie." He was not dazzled 

 by the latter ; but whilst avoiding 

 its extravagances and premature 

 generalisations which then flooded 

 Cerman science, he always appre- 

 ciated the search for the connection 

 and unity of all the things of nature 

 which was characteristic of that 

 school. Baer stood, historically and 

 philosophically, in the middle be- 

 tween the extreme morphological 

 and genetic views rejiresented 

 respectively by Cuvier before and 

 by Darwin after him. Already in 

 1815, when studying under Dol- 

 linger at Wiirzburg, he was guided 

 by the idea that " nature follows in 

 her creations certain general themes 

 (types), and that she varies these in 

 the different species." Von Baer 



also combined the geographical and 

 anthropological interest, so largely 

 represented by Humboldt and 

 Ritter, with his morphological 

 and genetic studies. In fact, it is 

 doubtful whether in any naturalist 

 of the very first order the different 

 interests which the nineteenth 

 century inherited and created were 

 more equally and impartially bal- 

 anced than in him. The embryo- 

 logical researches of von Baer 

 stimulated many ardent students in 

 ( Jermany, such as Purkinje, Rathtke, 

 Bischoff, and it is mainly through 

 them that this branch of science 

 was cultivated and made generally 

 known. The name of the distant or- 

 iginator thus became .somewhat for- 

 gotten, so that in French science we 

 do not find von Baer as frequently 

 and appreciatively mentioned as he 

 deserves. Ample information on von 

 Baer's scientific and personal char- 

 acter can be found in later publica- 

 tions : foremost in his ' Auto- 

 biography,' published in 186.^) ; in 

 his 'Life,' by Stieda (1877) ; and in 

 an elaborate work by Professor R. 

 Stolzle, entitled ' K. E. von Baer 

 und seine Weltanschauung' (Re- 

 gensburg, 1897). This work con- 

 tains very ample and useful refer- 

 ences and extracts from Baer's 

 writings and correspondence. Very 

 important are also von Baer's 

 miscellaneous writings and essays, 

 which were published by Vieweg 

 in Brunswick, in three parts (2nd 

 ed., 1886). 



