Table titled Summary of mutants obtained by GP, JAR and KMD up to December 1950"

Assignation between Pontecorvo, Dr Joseph Alan Roper and the National Research Development Corporation for the invention the subject of Patent Applications numbers 24907/51 and 5394/52

Agreement between Pontecorvo, Dr Joseph Alan Roper, the University of Glasgow, and the National Research Development Corporation relating to the exploitation of the inventions the subject of Patent Applications numbers 24907/51 and 5394/52

Correspondence between Pontecorvo and Dr Joseph Alan Roper about the biographical introduction to the Cancer Surveys publication, which honoured Pontecorvo on his 80th birthday

Letter to Pontecorvo from Joseph Alan Roper concerning summary of the "Porton programme" and the study of genetic control of penicillin titre

Copy of a letter from Pontecorvo to Dr M Zvegintzov of the National Research Development Corporation enclosing a draft report on research to date titled Controlled breeding of microorganisms irrespective of the occurence of sexual reproduction

Draft of Roper and Hopwood's typescript draft of the Pontecorvo article for the Cancer Surveys publication

Draft typescript copy of a report by Pontecorvo and Dr Joseph Alan Roper titled Synthesis by a process other than that of sexual reproduction of strains of microorganisms associating and re-combining properties present in two or more different strains

Letter to Pontecorvo from M M Green concerning Dr Joseph Alan Roper's experiments with the bi genes in diploid nuclei and its similarity with Green's work on Drosophila

Correspondence between Pontecorvo, Dr Giuseppe Sermonti and Dr Joseph Alan Roper concerning the National Research Develpment Corportion's involvement in developing their patents on the Synthesis of Strains of Micro-organisms and distribution of income from the NRDC between the inventors

Agreement between Pontecorvo, Dr Joseph Alan Roper, Dr Giuseppe Sermonti and the University of Glasgow and the National Research Development Corporation relating to the exploitation of the inventions the subject of Patent Applications Numbers 24907/51 and 5394/52

Typescript draft lecture notes titled Genetics and microbiology

Typescript draft lecture notes titled Genetic analysis without sexual reproduction be means of polyploidy in A. Nidulans

Letter to Pontecorvo from Professor Hermann Joseph Muller concerning Muller's comments on Joseph Alan Roper's paper (based on Pontecorvo's ideas) on allelism and its discussion of the "position effect" and his comments on another paper about radiation effects

Copy of a letter from Pontecorvo to Professor Hermann Joseph Muller asking for his comments and opinion on two of his two typescript draft papers and giving an update of Dr Joseph Alan Roper's work

Minute of Agreement between Pontecorvo, Dr Joseph Alan Roper, and Dr Giuseppe Sermonti

Letter to Pontecorvo from Curt Stern commenting on a abstract for a paper by Pontecorvo and Joseph Alan Roper on somatic [crossing-over]

Correspondence between Pontecorvo and Dr Sol Speigelman concerning Speigelman's interest in engaging with yeast genetics and Pontecorvo's developments with Aspergillus nidulans

Ccorrespondence between Pontecorvo and Dr Sterling Howard Emerson discussing Pontecorvo's plan to produce heterozygous diploids in Neurosporan with Dr Joseph Alan Roper and the difficulties in achieving this

Correspondence between Pontecorvo and Professor Charles Leonard Huskins concerning Pontecorvo and Dr Joseph Alan Roper's research into diploids in Aspergillus nidulans and somatic recombination