Damon, as far as I can tell, the men who are reported to be part of the 13th Arkansas Cavalry were prisoners of war, and were members of Clarkson's battalion, which suggests that the 13th Arkansas Cavalry might have been a temporary or interim designation. I doubt if it was a clerical error on the part of the prison staff, since they were captured at various dates from the summer of 1862 through early 1863.