severe overwork and annoyance, and Baer himself certainly 

 regretted it. "Generally I cannot decide," Baer wrote in 

 the same letter, "whether I behaved correctly by making 

 this vow, but I can confirm that I have injured myself 

 deeply, perhaps even too deeply. Later it seemed to me 

 that I had lost the best blood of my heart." 



Discussing the contents of this truly tragic letter, 

 B. E. Raikov correctly concluded that "there is no basis 

 for placing responsibility for the change in Baer's scien- 

 tific studies upon conditions in Russia. Not the Russian, 

 but the Prussian conditions of his life created in him 

 this attitude which led him to a decision so unfortunate 

 for science." 



However, in the 1840s Baer's interest in embryology 

 reawakened, undoubtedly in connection with his professorial 

 activity in the Petersburg Medical -Surgical Academy, where 

 he taught comparative anatomy and physiology, in which course 

 embryology figured significantly (114) . In connection with 

 teaching the science so near to his interest, Baer intended 

 in 1843 to publish a Latin "essay on the history of develop- 

 ment of men and other animals" (CONSPECTUS HISTORIAE 

 EVOLUTIONIS HOMINIS ET RELIQUORUM ANIMALIUM) in 

 twelve to fifteen papers with two tables of illustrations. 

 In 1844 invited the conference of the Academy of Science to 

 publish an atlas in Russian on this topic comprising forty 

 papers and 150 drawings. A report by Baer on the plan of 

 this publication was fully published in E. N. Pavlovskii's 

 K. M. BAER AND THE MEDICAL -SURGICAL ACADEMY. The 

 following parts of this document are interesting: 



New investigations in 'developmental history' 

 which have already been published are still 

 little known in Russia .... Consequently 

 it is reasonable now to wish for a textbook 

 on one branch of physiology developing in 

 recent times. This branch is riot only impor- 

 tant for physicians, and for naturalists 

 generally, but it also illuminates other parts 

 of physiology and anatomy. Once I dared to 

 hope that I possessed sufficient knowledge 

 in this subject .... 



464 



