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Typewritten letter
Typewritten letter
Handwritten note, image of von Frisch, and short poem, regarding von Frisch's recent Nobel Prize win
Typewritten letter
Short note on Twitty twin genes and Ambylstoma backcrosses in reply to Hamburger's letter. Twitty mentions Lipsett's hybridization of A. tigrinum & A. mexicanum.
Discussion of meeting with Ronald Oppenheim and behavioral embyology
Note on Triturus eggs sent to Hamburger. On his concerns on spending the summer in Woods Hole. Short note on his collaboration with Lehman and on Takahashi.
Letter from Norway
Handwritten letter, 2 pages
On the application of Miss Eggers.
On the Growth Society and their next symposium.
On his poem for Baltzer's birthday.