Thanks for the heads up, Alan---as always. It appears the National Parks Service's 'Civil War Soldiers & Sailors System' website also has the two units confused. See excerpt below from CWSS website:

CONFEDERATE GEORGIA TROOPS

16th Battalion, Georgia Cavalry (State Guards)

16th Cavalry Battalion was assembled in May, 1862, at Big Shanty, Georgia, and was composed of six companies. It served in East Tennessee and Southwest Virginia and took part in the engagements at Blue Springs, Bean's Station, Cloyd's Mountain, and Marion. In January, 1865, the battalion merged into the 13th Georgia Cavalry Regiment. Lieutenant Colonels F.M. Nix and Samuel J. Winn, and Major Edward Y. Clarke were its commanding officers.