Hamburger, Viktor
On the proofs for their chapter in "Analysis of Development".
Handwritten letter, 2 pages
On his paper on fibronectin publsihed in Developmental Brain Research. On his upcoming paper on axonal guidance in the sympathetic system of the chick, dedicated to Hamburger. On his ongoing research on guidance cues.
On Holtfreter's recent experiments "to show that 'inducing agents' diffuse through a barrier of agar and of cellophane." On other induction experiments.
On his "working hypothesis that the control of cell type differentiation of a cell lineage during vertebrate ontogenesis can be divided into two: The immediate control is the direct control of genes to express the cell type. The remote control is exercised by a specific cell event which may or may not be influenced by the factors coming from the outside of the cell lineage. The completion of remote control activates the immediate control of a specific cell type within the cell lineage."
On a recent manuscript by Harris and his criticism of Steinberg. On the death of Waddington.
Season's greetings
On his upcoming research appointment with Dr. Yerkes at the Yale Laboratories of Primate Biology.
Private letter on Weigold's health condition.
On his article 'Cell Type Expression mediated by Cell Cycle Events and signaled by Mitogens and Growth Inhibitors'. On the regulation of meso-endodermalization of amphibian ectoderm.