My understanding is that Glisson and Gleason was probably the same. I am one of the Glisson's from North Carolina. The Glisson's came to Va. from England, then to North Carolina and then branched out to different states. A lot of them went to Tenn., South Carolina, Ga., Florida. My e-mail address is Barbara11306@aol.com if you have any questions I could help you with, although the history I have the name is Glisson.