My wife's mother's family (mother-in-law was a Jones) had links to some of the places mentioned on this thread - Marl Farm, Snottyn Farm (possibly later changed to Ffarm Tyddyn), Seguryn and Maes Glas, also Penbont and Pencreuddyn, plus others in the Llangwstenin area. The Jones family had a lot of children around the period 1880 to 1960, two brothers emigrated to Kansas in 1910 taking most of their kids with them, my wife's grandfather was one the eldest children and stayed here. There is a link to the Davies family at Marl Farm, as one of the Jones girls married a Davies - Tommy (Tomi Marl) Davies, mentioned earlier, being one of the offspring.
Quite a few of the family are buried in Llangwstenin churchyard.
Hopefully anneelaine is looking in and can come up with some names from that period and see if they match up. I have drawn up quite a bit of the family tree, based on information from my mother-in-law.