Hi Bob,
These are the only John And Elisabeth Jones on the 1881 census.
But they dont match what you've got.
Hope it helps,
Allan
Dwelling: Bk High Street
Census Place: Festiniog, Merioneth, Wales
Source: FHL Film 1342333 PRO Ref RG11 Piece 5551 Folio 49
Page 91
Marr Age Sex Birthplace
John JONES M 49 M Dolbenmaen, Caernarvon, Wales
Rel: Head
Occ: Gy Machiner (Slate Quarrer)
Elizabeth JONES M 45 F Llanystumdwy, Caernarvon, Wales
Rel: Wife
Occ: Gy Machiner Wife
John B. JONES U 25 M Llanystumdwy, Caernarvon, Wales
Rel: Son
Occ: Gen Labourer (Unemployed)
Llewelyn B. JONES U 19 M Festiniog, Merioneth, Wales
Rel: Son
Occ: Printer Compositor
Jane Ellen JONES U 12 F Festiniog, Merioneth, Wales
Rel: Daur
Occ: Scholar
William JONES 9 M Festiniog, Merioneth, Wales
Rel: Son
Occ: Scholar
Hannah JONES 4 F Festiniog, Merioneth, Wales
Rel: Daur
Dwelling: 12 Cwmorthin Rd
Census Place: Festiniog, Merioneth, Wales
Source: FHL Film 1342333 PRO Ref RG11 Piece 5551 Folio 97
Page 52
Marr Age Sex Birthplace
John JONES M 40 M Llanllethid, Caernarvon, Wales
Rel: Head
Occ: Quarryman
Elizabeth JONES M 37 F Festiniog, Merioneth, Wales
Rel: Wife
John JONES 7 M Festiniog, Merioneth, Wales
Rel: Son
Occ: Scholar
Owen JONES 3 M Festiniog, Merioneth, Wales
Rel: Son
Jane WILLIAMS 15 F Maentwrog, Merioneth, Wales
Rel: Visitor
Occ: Domestic
Ellin JONES 1 F Festiniog, Merioneth, Wales
Rel: Daur
William A. WILLIAMS 23 M Llanllyfni, Caernarvon, Wales
Rel: Visitor
Occ: Quarryman
Dwelling: Maenofferen Ter
Census Place: Festiniog, Merioneth, Wales
Source: FHL Film 1342333 PRO Ref RG11 Piece 5550 Folio 135
Page 95
Marr Age Sex Birthplace
John JONES M 28 M Caernarvon, Wales
Rel: Head
Occ: Slate Quarrier
Elizabeth JONES M 25 F Caernarvon, Wales
Rel: Wife