Bundle of correspondence between Pontecorvo and Professor Boris Ephrussi concerning three mutant strains of yeast Pontecorvo sent to Ephrussi to be used in experiements for his metabolic work

Correspondence between Pontecorvo and Professor Boris Ephrussi concerning Ephrussi's work on hybrid clones and Pontecorvo's trip from Baltimore to Denver in the summer

Letter sent to Pontecorvo from Professor Boris Ephrussi regarding Ephrussi's research work

Bundle of correspondence between Pontecorvo and Professor Boris Ephrussi concerning an update on Pontecorvo's current research on allelism and pseudo-allelism using Aspergillus

Bundle of correspondence between Pontecorvo and Professor Boris Ephrussi relating to Pontecorvo's study into the functions of nucleic acids in the nucleus for his research on gene reproduction

Photographs of Pontecorvo with attendees of the Middlebury Conference on Biology Teaching, 1971

Boris Ephrussi and his soon to be wife Harriet Taylor, at Cold Spring Harbor, 1946

Letter to Pontecorvo from Professor Boris Ephrussi in response to Pontecorvo's letter asking for advice on what to do about the job offered at Harvard University

Correspondence between Pontecorvo and Professor Boris Ephrussi concerning Pontecorvo's decision to turn down the offer of a job at Harvard

Bundle of correspondence between Pontecorvo and Professor Boris Ephrussi concerning Pontecrovo's thoughts on Ephrussi's publication The William Withering Memorial Lectures, (1952)

Letter to Pontecorvo from Professor Boris Ephrussi responding to what Pontecorvo described as "the nightmare of defining "genetic" properties and changes"

Bundle of correspondence between Pontecorvo and Professor Boris Ephrussi concerning Pontecorvo nominating Ephrussi to receive an honorary LLD degree from the University of Glasgow

Bundle of correspondence between Pontecorvo and Professor Boris Ephrussi concerning Pontecorvo's discovery of a "method of haploidization"

Photograph of Boris Ephrussi and his wife Harriett Ephrussi-Taylor at Cold Spring Harbor, 1946

Copy of a letter from Pontecorvo to Professor Boris Ephrussi concerning Ephrussi's research on hybrid clones

Letter to Pontecorvo from Professor Boris Ephrussi in which he asks Pontecorvo for the procedure and results of his recent experiement to revert chromosome loss in human-mouse hybrids

Bundle of correspondence between Pontecorvo, Professor Boris Ephrussi and Professor Henry Harris concerning Harris's paper on heterokaryons

Bundle of correspondence between Pontecorvo and Professor Taco Hajo Van den Honert concerning Pontecorvo's suggestions of candidates for the new Professor of Genetics at Leiden University

Photographs of Pontecorvo with friends and colleagues at the Genetique Somatique Conference, Inserm, 1979, and in Sri Lanka, 1978, plus some of colleague Dan Lewis

Jacques Monod, André Michel Lwoff, Boris Ephrussi and one other unidentified person sitting on a porch of a house at Cold Spring Harbor, 1946