It sounds as if Sitrman's Cavalry Battalion was part of Fagan's Division during the Camden Expedition? But when I look in the OR for the organization of Fagan's Division, I don't see Stirman listed as a commander.

Was Stirman's Battalion consolidated with a regiment in Fagan's division?

United States. War Dept.. The War of the Rebellion: A Compilation of the Official Records of the Union And Confederate Armies. Series 1, Volume 34, In Four Parts. Part 1, Reports., Book, 1892; digital images, (http://texashistory.unt.edu/ark:/67531/metapth146033/m1/813/?q=Camden Gause : accessed July 05, 2012), University of North Texas Libraries, The Portal to Texas History, http://texashistory.unt.edu; crediting UNT Libraries, Denton, Texas.