Sorry, the book is pretty much focused on arms & equipment. Snipped from Dyer's Compendium, however : "1st Brigade, 2nd Division, Army of the Frontier, to May, 1863. 2nd Brigade, 1st Cavalry Division, District of Southeast Missouri, to August, 1863. 2nd Brigade, 1st Cavalry Division, Arkansas Expedition, to December, 1863." So, transferred from Army of the Frontier to Dist of SE Missouri in May '63. Ought to be simple to see who was in the 2nd Brig. of 1st Cavalry Division. Think that's Davidson's. If I used to know those facts, I've forgotten.