NPS-CW-S&SS shows:

James C. Adams
Regiment Name 4th Virginia Reserves. (Preston's Regiment. 5 Reg't Virginia Reserves.)
Side Confederate
Company B - Grayson Reserves, Grayson County, Dublin Rendezvous; Capt John W. Warrick
Soldier's Rank_In Private
Soldier's Rank_Out Private
Film Number M382 roll 1

4th Regiment, Virginia Reserves

"Units of the Confederate States Army" by Joseph H. Crute, Jr. contains no history for this unit.

A Guide to Virginia Military Organizations, 1861-1865 by Lee A. Wallace, Jr, pg 222

4th Regt Va Resaerves
Preston, Robert Taylor, Col., 1864-1865
Formerly known as the 5th Regt., and as Preston's Regt., this command was organized August 27, 1864, as a battalion under Lt. Col. Robert T. Preston, which was known as Preston's Bn Va Reserves. The battalion was composed of seven companies, which became Companies A to F and Co H, of the 4th Regt. Companies G, I and K, were formed by transfer of members from other companies of the battalion. The regiment was organized November 24, 2864, by order from Hdqrs. Dept of Western Virginia and East Tennessee, dated September 20, 1864. It was recognized and designated as the 4th Regt Va Reserves by S.O. No. 48, A&IGO, dated February 27, 1865.

Elisha Adams
Regiment Name 4th Virginia Reserves. (Preston's Regiment. 5 Reg't Virginia Reserves.)
Side Confederate
Company B - Grayson Reserves, Grayson County, Dublin Rendezvous; Capt John W. Warrick
Soldier's Rank_In Private
Soldier's Rank_Out Private
Film Number M382 roll 1
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Records also show:

James C. Adams
Regiment Name 13th Virginia Cavalry. (16 Batt'n Virginia Cav. 5 Va. Cav., 12 Mos., 1861-2.)
Side Confederate
Company A - Southampton Cavalry; Southampton County
Soldier's Rank_In Private
Soldier's Rank_Out Private
Film Number M382 roll 1

13th Regiment, Virginia Cavalry (12th Months, 1861-62)

13th Cavalry Regiment was formed in July, 1862, using the 16th Battalion Virginia Cavalry as its nucleus. The men were from Petersburg and the counties of Southampton, Sussex, Prince George, Surry, and Nansemond. It was assigned to W.H.F. Lee's, Chambliss', and Beale' Brigade in the Army of Northern Virginia. The unit was active in the conflicts at Fredericksburg, Brandy Station, Upperville, Hanover, Gettysburg, Bristoe, Kelly's Ford, and Mine Run. Later it participated in The Wilderness Campaign, the defense of Petersburg and Richmond, and the Appomattox operations. This regiment had 298 men in action in Gettysburg and surrendered on April 9, 1865, with 10 officers and 78 men. The field officers were Colonels John R. Chambliss, Jr. and Jefferson C. Phillips; Lieutenant Colonels Alexander Savage and Thomas H. Upshaw; and Majors Benjamin W. Belsches, Joseph E. Gillette, and Benjamin F. Winfield.