I must also plead ignorance of the procedures for finding out about Scottish ancestors which is something I am trying to correct.
https://www.rootschat.com/forum/index.php?topic=24468.0Basically everything you need to get started is at
www.scotlandspeople.gov.uk, which is pay-per-view but modestly priced. Scottish civil registration certificates are much more informative than English ones. In particular, a death certificate tells you the full names of the parents of the deceased, including the deceased's mother's maiden surname (assuming of course that the informant knew that).
I see that both James and Elizabeth's deaths were registered in Banff, so if you go to Scotland's People you can instantly download images of the death certificates of Elizabeth in 1869 and James in 1873, which will cost you £3 (£1.50 each).