mean only in Jena. 5 But it is not evident, first, that 

 Tredern's dissertation was accomplished in Jena, and, second, 

 that Oken had any connection to it. In 1808 Oken was not in 

 a position to evaluate the significance of Tredern's 

 dissertation, so that even after ten years he could write 

 about Pander's dissertation in statements indicating a 

 complete misunderstanding of the subject. (52) 



In the spring of 1808, Tredern passed the examination 

 rigorosum honorably, and, after defending his dissertation 

 on April 4, he received the degree of Doctor of Medicine and 

 Surgery. Tredern thereupon returned to GSttingen, where he 

 continued working intensively on the study of avian develop- 

 ment. It was about that second period of Tredern's life in 

 Gottingen that the notary Shtender had the memories mentioned 

 above. This letter, lost by Baer and recovered by Stieda, is 

 interesting enough for us to extract detailed quotations. 



Tredern, my friend from student years, will always 

 live in my memories. I cannot give a convincing 

 answer to the question as to where he disappeared. 

 In autumn, 1808, nearly within half a year after my 

 arrival in Gottingen, Tredern also was present. 



He was a man of strong physique, 5 feet 3 inches tall, 

 with dark hair, large whiskers, brown eyes, and a 

 fairly large, slightly arched nose. He was, according 

 to our judgment, about twenty-four years old. 6 He had 

 a quiet and at the same time an active character. He 

 lived very economically, did not indulge in any vices, 

 and constantly wore a suit of dark brown cloth, gray 

 trousers, and a black cloth hat with a sharp, downward- 

 hanging brim. He carried a brush like those carried 

 by our military people thirty years ago. He was 

 present only with small groups of people, especially 

 with Blumenbach. He spent all of his time on the 

 incubation of the eggs of different birds, mainly 

 chickens, and in drawing the embryos from the beginning 

 of incubation to the time the chick hatched from the 



5. Oken, ISIS, No. 192 - 193 (1817), p. 1531. 



6. In 1808 Tredern was actually twenty-eight years old 



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