| RefNo | Title | Date |
| IM/GA/GRS/6223 | Laidlaw, Sir Patrick Playfair | nd |
| EC/1927/09 | Laidlaw, Sir Patrick Playfair: certificate of election to the Royal Society | |
| RR/38/74 | Referee's report by Patrick Playfair Laidlaw, on a paper 'Reduced haematin and haemochromogen' by Robert Hill | April 1929 |
| RR/41/127 | Referee's report by Patrick Playfair Laidlaw, on a paper 'The porphyrin of component c of cytochrome and its relationship to other porphyrins' by Robert Hill and David Keilin | September 1930 |
| RR/41/90 | Second referee's report by Patrick Playfair Laidlaw, on a paper 'The reaction of the dental pulp to peripheral injury of the dentine' by E Wilfred Fish | January 1931 |
| RR/42/54 | Referee's report by Patrick Playfair Laidlaw, on a paper 'On the histological evidences of the organic content and reactions of marsupial enamel, with a note on human enamel' by Evelyn Sprawson | April 1930 |
| RR/47/25 | Referee's report by Patrick Playfair Laidlaw, on a paper 'The cultivation of vaccinia virus A new series of subcultures in cell-free medium' by G Hardy Eagles and A H H Kordi | June 1932 |
| RR/44/90 | Referee's report by Patrick Playfair Laidlaw, on a paper 'The tightness of the teeth, considered as a problem concerning the equilibrium of a thin incompressible elastic membrane' by John Lighton Synge | June 1932 |
| NLB/57/392 | Copy letter from Robert William Frederick Harrison, Assistant Secretary of the Royal Society; to Dr PP [Patrick Playfair] Laidlaw, FRS | 30 October 1919 |
| RR/58/47 | Referee's report by John Charles Grant Ledingham, on a paper 'A new group of filterable organisms' by Patrick Playfair Laidlaw and William Joseph Elford | March 1936 |
| RR/62/54 | Referee's report by Patrick Playfair Laidlaw and Alan Sterling Parkes, on a paper 'Inhibition of action of pituitary hormones by animal sera' by K W Thompson and Harvey Williams Cushing | [October 1936] |
| RR/37/138 | Referee's report by Patrick Playfair Laidlaw, on a paper 'Artefacts as a guide to the chemistry of the cell' by Charles Edward Walker | June 1928 |
| NLB/71/895 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to Dr. [Patrick Playfair] Laidlaw, FRS | 1 December 1928 |
| RR/49/56 | Referee's report by Patrick Playfair Laidlaw, on a paper 'Inflammation in caterpillars of Lepidoptera' by Gordon Roy Cameron | [January 1934] |
| RR/36/5 | Referee's report by Patrick Playfair Laidlaw, on a paper 'Studies in the microchemistry of the cell. I.—The chromatin content of normal and malignant cells, as demonstrated by Feulgen's “Nuclealreaktion."' by Reginald James Ludford | [December 1927] |
| HD/25/21 | Presentation album for Henry Dale on his retirement from the National Institute for Medical Research | 30 September 1942 |
| NLB/57 | New Letter Book volume 57, copy letters sent from Royal Society administration | 27 June 1919-27 February 1920 |
| RR/48/90 | Referee's report by Patrick Playfair Laidlaw, on a paper 'The effects of vitamins C deficiency on tooth structure in guinea-pigs' by E Wilfred Fish and Leslie J Harris | [July 1933] |
| RR/41/89 | Referee's report by Patrick Playfair Laidlaw, on a paper 'The reaction of the dental pulp to peripheral injury of the dentine' by E Wilfred Fish | December 1930 |