| Reference number | Title | Date |
| NLB/59/250 | Copy letter from Edwin Deller, Assistant Secretary of the Royal Society; to [Charles Tate] Regan Esquire, FRS | 30 July 1920 |
| RR/41/84 | Referee's report by Charles Tate Regan, on a paper 'The origin and development of the pericardium and kidneys in Ostrea' by Wilfred Fernando | October 1930 |
| NLB/54/442 | Copy letter from Robert William Frederick Harrison, Assistant Secretary of the Royal Society; to [Charles] Tate Regan Esquire, FRS | 17 May 1917 |
| RR/27/49 | Referee's report by Charles Tate Regan, on a paper 'The defensive spines of fishes, living and fossil, and the glandular structure in connection therewith, with observations on the nature of fish venoms' by H Muir Evans | May 1922 |
| MC/31/25 | Letter from [Charles] Tate Regan, Secretary, Natural History Museum, to the [Royal Society] | 4 March 1916 |
| NLB/58/260 | Copy letter from Edwin Deller, Assistant Secretary of the Royal Society; to [Charles] Tate Regan Esquire, Secretary of the Challnger Committee and FRS | 13 April 1920 |
| RR/29/16 | Referee's report by Charles Tate Regan, on a paper 'On the classification and phylogeny of the teleostei arterioles' by H K Kyle | January 1923 |
| NLB/55/221 | Copy letter from Robert William Frederick Harrison, Assistant Secretary of the Royal Society; to [Charles Tate] Regan, FRS | 22 January 1918 |
| NLB/55/264 | Copy letter from Robert William Frederick Harrison, Assistant Secretary of the Royal Society; to Professor [John Bretland] Farmer, FRS | 07 February 1918 |
| NLB/60/312 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to [Charles Tate] Regan Esquire, FRS; The Challenger Society, Natural History Museum | 17 January 1921 |
| NLB/60/484 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to [Charles Tate] Regan Esquire, FRS | 14 February 1921 |
| RR/47/6 | Referee's report by Charles Tate Regan, on a paper 'The Genus Hyracotherium. A revision and description of new specimens found in England' by Clive Forster-Cooper | April 1932 |
| RR/49/89 | Referee's report by Charles Tate Regan, on a paper 'The habits and structure of pseudapocryptes lanceolatus, a fish in the first stages of structural adaptation to aerial respiration' by B K Das | [April 1934] |
| RR/28/72 | Referee's report by Charles Tate Regan, on a paper 'Some peculiarities of the blood-vascular system of the porbeagle shark (Lamna cornubica)' by Richard Higgins Burne | [June 1923] |
| RR/53/58 | Referee's report by Charles Tate Regan, on a paper 'The brain of Gadus, with special reference to the medulla oblongata and its variations according to the feeding habits of different gadidae—I' by H Muir Evans | [November 1934] |
| RR/59/65 | Referee's report by Charles Tate Regan, on a paper 'A comparative study of the brains in pleuronectidae' by H Muir Evans | [August 1936] |
| NLB/65/683 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to Sir Sidney [Frederic] Harmer, FRS | 7 December 1923 |
| NLB/62/817 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to [Charles Tate] Regan Esquire, FRS | 12 May 1922 |
| NLB/65/567 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to Sir Sidney [Frederic] Harmer, KBE, FRS | 21 November 1923 |
| RR/47/41 | Referee's report by Charles Tate Regan, on a paper 'Further observations on the medulla oblongata of cyprinoids ; and a comparative study of the medulla of clupeoids and cyprinoids with special reference to the acoustic tubercles' by H Muir Evans | May 1932 |
| NLB/65/95 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to Professor [Frederick William] Gamble, FRS; circulated to all members of the Zoology Committee | 26 July 1923 |
| NLB/65/641 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to [Charles] Tate Regan Esq., FRS | 1 December 1923 |
| NLB/65/72 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to Sir Sidney [Frederic] Harmer, FRS | 24 July 1923 |
| NLB/67/332 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to [Charles] Tate Regan Esq., FRS | 6 December 1924 |
| NLB/67/282 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to Professor [David Meredith Seares] Watson, FRS | 28 November 1924 |
| NLB/67/221 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to Sir Sidney [Frederic] Harmer, KBE, FRS | 14 November 1924 |
| NLB/69/181 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to [Charles] Tate Regan Esq., FRS | 23 January 1926 |
| NLB/71/277 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to Sir Sidney [Frederic] Harmer, K.B.E., FRS | 13 March 1928 |
| NLB/70/884 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to [Charles] Tate Regan Esq., FRS | 29 October 1927 |
| NLB/71/419 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to [Charles] Tate Regan., FRS | 8 May 1928 |
| NLB/71/842 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to the Editor, the Encyclopaedia Britannica, 80 Regent Street, W1 | 14 November 1928 |
| NLB/71/860 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to A. E. Ellis Esq., Lancing College, Shoreham, Sussex | 20 November 1928 |
| EC/1917/11 | Regan, Charles Tate: certificate of election to the Royal Society | |
| RR/31/44 | Referee's report by Arthur Smith Woodward, on a paper 'The morphology of a rare oceanic fish, Stylophorus chordatus, Shaw; based on specimens collected in the Atlantic by the “Dana” expeditions, 1920-1922' by Charles Tate Regan | 5 February 1924 |
| RR/28/74 | Referee's report by Charles Tate Regan, on a paper 'Heat, moisture, and animal life in deserts' by Patrick Alfred Buxton | [November 1923] |
| RR/31/43 | Referee's report by Sidney Frederic Harmer, on a paper 'The morphology of a rare oceanic fish, Stylophorus chordatus, Shaw; based on specimens collected in the Atlantic by the “Dana” expeditions, 1920-1922' by Charles Tate Regan | 10 December 1923 |
| RR/31/41 | Referee's report by David Meredith Seares Watson, on a paper 'Dwarfed males parasitic on the females in oceanic angler-fishes (Pediculati ceratioidea)' by Charles Tate Regan | 1 December 1924 |
| NLB/70/549 | Copy letter from Francis Alexander Towle, Assistant Secretary of the Royal Society; to [Charles] Tate Regan Esq., FRS | 16 May 1927 |
| NLB/69/379 | Copy letter from [James Hopwood Jeans, Secretary of] the Royal Society; to to Prof. [Thomas Renton] Elliott, FRS | 24 March 1926 |
| RR/41/83 | Referee's report by Charles Tate Regan, on a paper 'The origin of the mesoderm in the gastropod Viviparus (= Paludina)' by Wilfred Fernando | October 1930 |
| RR/49/87 | Referee's report by Charles Tate Regan, on a paper 'On the physiology of respiration in fishes I. On the bionomics, structure and physiology of respiration in an esturine air-breathing Gobioid fish' by B K Das | [December 1933] |
| RR/34/8 | Referee's report by Charles Tate Regan, on a paper 'Studies in colour changes of fish. - Part II. —An analysis of the colour patterns of the dab. - Part III. —The action of nicotin and adrenalin in the dab. - Part IV. —The action of caffeine in the dab, and a theory of the control of colour changes in fish' by H R Hewer | nd [1926] |
| RR/30/44 | Referee's report by Charles Tate Regan, on a paper 'A contribution to the anatomy and physiology of the air-bladder and Weberian ossicles in Cyprinidae' by H Muir Evans | [November 1924] |
| RR/31/42 | Referee's report by David Meredith Seares Watson, on a paper 'The morphology of a rare oceanic fish, Stylophorus chordatus, Shaw; based on specimens collected in the Atlantic by the “Dana” expeditions, 1920-1922' by Charles Tate Regan | nd [1923] |
| RR/33/110 | Referee's report by Charles Tate Regan, on a paper 'The development of the chondrocranium of the eel (anguilla vulgaris), with observations on the comparative morphology and development of the chondrocranium in bony fishes' by J R Norman | October 1925 |
| RR/35/56 | Referee's report by Charles Tate Regan, on a paper 'The bionomics of certain air-breathing fishes of India, together with an account of the development of their air-breathing organs' by B K Das | June 1927 |
| RR/41/79 | Referee's report by Charles Tate Regan, on a paper 'A comparative study of the brains in British cyprinoids in relation to their habits of feeding, with special reference to the anatomy of the medulla oblongata' by H Muir Evans | December 1930 |
| RR/52/52 | Referee's report by Charles Tate Regan, on a paper 'A study of the correlation between the feeding habits and the structure of the hind brain in the South Indian cyprinoid fishes' by B S Bhimachar | November 1934 |
| RR/47/71 | Referee's report by Charles Tate Regan, on a paper 'Studies in animal movement, I. The movements of fish with special reference to the eel' by James Gray | June 1932 |
| MC/32/42 | Letter from [Charles] Tate Regan, Secretary, The Challenger Society for the promotion of the study of Oceanography, Natural History Museum, Cromwell Road, S.W, to the [Royal Society] | 1 January 1917 |