I've seen it spelled every which way. I know that ours went by Jimmerson for a while and then all of a sudden changed it to Jamerson. I think we could look under Jemison, Jemmison, Jimmison, Jamison,etc.. the list would go on and on. Could you send me your Gedcom or a report to my email address with your oldest Jimmerson/Jemerson ancestor and like 4 generations down? Maybe I can find a link in there somewhere. I truly would like to know where our "J" lines intersect!