At first glance, I don't think I have your Mitchells. However, most of my lot came from Cumnock, and James is a common name throughout, as is Robert. The only Mitchell I have going to America was Andrew, who emigrated in 1753 to Philadelphia and who was for some time a major in the New York Militia during the Revolutionary War. His grandson, William, founded Kendallville in Indiana. I will have a good look through my stuff and see if I can come up with anything - in earlier times Cumnock was not that large a place and one would imagine that Mitchells might be connected in some way. I'll see what I can do. Best wishes, Dorothy