may also help. I will mail you privately with a couple of attachments that will give you an idea of what the tartans are like.
Moving on to the question of tracing your James Devlin. I am faced with a similar situation to you. My immediate Devlin family are Scottish and I traced back to my Great, Great Grandfather John Devlin who left Ireland for Scotland in about 1870 quite easily.
BUT researching in Ireland is a nightmare ! Not much is computerised and the records are all over the place, where they exist at all ! I know that John's mum and dad were called Archibald Devlin and Mary McVey. Archibald is a very uncommon name for a catholic and I still haven't managed to locate them or get any further after months of trying.
If you know where James was married perhaps you could get a copy of his wedding certificate. That may well tell you the names of his parents, which in turn may give you more to go on.
If you think that James came from Omagh in Tyrone, then you need to commission some research to establish more. I don't feel able to recommend anybody in particular. You might like to check out ;