materialism of the beginning of the nineteenth century, which 

 is now called mechanical or metaphysical materialism. It is 

 not surprising that Baer's deep intellect could not be 

 reconciled with the primitive simplified ideas about develop- 

 ment coming out of the general principles of this materialism. 



Baer's negative relationship to materialism was charac- 

 terized by his concern about complex life processes, for which 

 he sought other than dead mechanical schemes. The possibility 

 of real scientific solution to the questions interesting him 

 in the first half of the nineteenth century was not yet 

 available, however. Instead, Baer was faced with idealistic 

 ideas, diligently propagated by the departments of German 

 universities. From Baer's endorsement of idealism comes the 

 beginning of his views about "The general and superior attitudes" 

 about the "essence" or "notion" governing the development of 

 individuals. Baer's idealistic discussions frequently go against 

 his specific ideas about ontogenic development, which are based 

 on strict and accurate observations. 



On a much greater level, Baer's idealistic opinions on 

 the evolution of the organic world remain consistent. Admitting 

 the natural origin and development of living creatures, because 

 otherwise a miracle would be required, Baer limited the 

 evolutionary process to lower systematic groups and did not 

 extend the idea to his types. In relation to the mobile powers 

 of evolution, Baer, especially in later years, decisively 

 objected to Darwin's materialistic point of view. His question 

 about evolutionary opinions extends, in general, beyond the 

 limits of the present book and requires further specialized 

 study. 



The second question discussed in Baer's second scholium 

 concerns the most important result of development as a whole, 

 "the increasing independence of the developing animal." 



The main stages of chick embryo development, discussed in 

 detail in the first part of the work, include the following: 

 1) growth of the rudiment (blastoderm) , whose unlimited part 

 constitutes the embryo; 2) separation of the embryo from the 

 remaining rudiment, but with the embryo remaining subordinated 

 to and supplying the rudiment with nutrient materials; 3) the 

 separation of the embryo from the egg parts outside the embryo, 



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