1911.29.87 Ammonite carved with an animal's head, forged fossil from Whitby donated by Percy Manning
Go here to find out more about one of his contemporary's in New College, and a friend, John Linton Myres.
Apparently Manning suffered from extreme aphasia which may have hampered his academic career, but it was also his pursuit of outside activities that caused him problems. He was excavating at Alchester during his 1892 examinations.
During the 1890s Manning began to collect extensivly. He gave some artefacts to the Ashmolean Museum and others to the Pitt Rivers Museum and the Bodleian Library. He worked with Thomas James Carter, a retired brickmaker and keen palaeontologist. Manning used him to 'collect information on local folklore and custom'. [DNB] Manning described his relationship with Carter:
It was as a collector of fossils that I first met Carter, but subsequently on turning my attention to folklore, it struck me that I might avail myself of his rambles over the country. He applied to his search for "old superstitions, stories, proverbs, words &c." - such was his commission - the same keenness and shrewdness with which he had hunted fossils. In every case he wrote his information down before bringing it to me, and it is a selection from his MSS., copied practically verbatim, that forms the main body of these papers. I have added some items collected by myself at first-hand ... For all else Carter is my authority. [Manning, 1902: 289]
Manning was part of the morris revival in Oxford, publishing an account of morris dancing in 1897 and equipping the Headington Quarry morris dancers for a performance in 1899. See here for more information about morris costume donated directly to the Museum by Carter, Manning's associate. He died in 1917 after some home war service, from pneumonia and was buried in Oxford.
Manning was a member of the Society from 1896 until 1917. He is first listed in the 1897 list of members he is mentioned as living at '44 Broad Street, Oxford (Beechfield, Watford). [Front Matter, Folklore, vol. 8, no. 1 March 1897 pp i-xii]  He does not appear to have ever held office in the Society.
In 1893 he published an account of May-Day at Watford, his family home in Folklore. [Manning, 1893: 403-4] This was the same year that he was removed from his Oxford college's books so he may have returned home in disgrace for a period. He is not listed as a member of the Society in this year.
In 1897 Manning read a paper at the 16 March meeting of the Folklore Society about 'Oxfordshire Seasonal Festivals', particularly May Day, Whitsuntide and the Lamb Ale. In his introduction he thanks 'Mr T.J. Carter of Oxford, who has been invaluable in collecting information for me'. [Manning, 1897: 307] He published this paper a year after he finally achieved his degree, and after he had decided to make Oxford his permanent home.
In 1902 Manning published the first of four articles in Folklore 'Stray Notes on Oxfordshire Folklore'. In part these had been read at a meeting of the Society on 26 March 1902 and were 'largely based on the collections of my old friend Thomas James Carter'. [Manning, 1902: 288] According to his DNB entry, the Folklore Society pressed him to write about Oxfordshire for its County Folklore series but they were not successful. He did, however, act as committee chairman for the Oxford Millenary Exhibition in 1912.
He read a paper Bringing in the Fly' to a meeting on 19 March 1913, which he concluded:
I think it is evident that we have here another instance, like the Boar's Head ceremony at Queen's College, of a folk-custom adopted by and preserved in academic usage,- "a fly in amber". [Manning, 1914: 205]
Manning donated a total of 219 artefacts to the Museum, of which a total of 195 are from England and 149 of those from Oxfordshire. The artefacts from England are listed here.
Percy Manning's manuscript collection and archive came to the University of Oxford in 1917. The archaeological papers were deposited in the Ashmolean Museum and other papers in the Bodleian Library. Percy Manning donated a large number of objects to the Ashmolean Museum during his lifetime, the Museum also purchased the bulk of his collection in 1921, after it had been put up for auction. As can be seen here, these items are not just archaeological, they also include items that would, in other collections, be considered to be 'social history' like an 'old latch from house in Cowley, Oxford' [AN1921.308], manacles from Oxfordshire [AN1921.455] and a Victorian constable's staff from the same county [AN1921.384]
 A list of the Folklore Society members in 'Front Matter' Folklore, Vol. 24, No. 1 (Mar., 1913), pp. i-xvii lists all members and the year they joined. Manning's entry reads:
1896. Manning, P. Esq. M.A. F.S.A. 6 St Aldate's, Oxford (Beechfield, Watford).
This is mysterious as he is not listed in 1896 in the list of members, but he is in the 1897 list as given above. From 1914 he is listed as living at 300 Banbury Road, Oxford.
Manning, Percy. 1893 'May-Day at Watford, Herts.' part of 'Folklore Miscellanea', Folklore Vol. 4, No. 3 (Sep., 1893), pp. 403-404
Manning, Percy 1897 'Some Oxfordshire Seasonal Festivals: with notes on morris dancing in Oxfordshire' Folklore Vol. 8, No. 4 (Dec., 1897), pp. 307-324
Manning, Percy 1902 'Stray Notes on Oxfordshire Folklore' Folklore Vol. 13, No. 3 (Sep. 29, 1902), pp. 288-295
Manning, Percy 1903 'Stray Notes on Oxfordshire Folklore (Continued)' Folklore Vol. 14, No. 1 (Mar., 1903), pp. 65-74
Manning, Percy 1903 'Stray Notes on Oxfordshire Folklore (Continued)' Folklore Vol. 14, No. 2 (Jun. 24, 1903), pp. 167-177
Manning, Percy 1903 'Stray Notes on Oxfordshire Folklore (Continued)' Folklore Vol. 14, No. 4 (Dec. 25, 1903), pp. 410-414
Manning, Percy 1914 'Bringing in the Fly' Folklore Vol. 25, No. 2 (Jun. 30, 1914), pp. 198-205
My thanks to Mike Heaney of the Bodleian Library, who wrote the DNB entry for Manning, for his help in compiling this section.