Jimmy, hi! The 154th was definitely a Memphis unit. It was based on the prewar 154th regt. TN militia, a Memphis outfit. When the war started, the men of this militia unit joined the Confederate army as a unit and got the War Dept. to allow them to join under their prewar number. The "Senior" in the title does not refer to the age of the men (as in the "Senior Reserves" of NC) but rather to the fact that the number "154" was an older, prewar designation.