Irene,
I found this on your Grandfather.
J. G. Walker
Private, Company D
Bourland's Regiment Texas Cavalry
Here is a short history of the unit.
CONFEDERATE TEXAS TROOPS
Bourland's Regiment, Texas Cavalry (Border Regiment)
Bourland's Cavalry Regiment was organized during the spring of 1863 and served in the Trans-Mississippi Department. The purpose of this unit was to guard the northern border of Texas and at times, therefore, was called the Border Regiment. It confronted the Federals in the Indian Territory and Texas, and on January 1, 1865, it reported 4 officers and 564 men fit for duty. The regiment surrendered in June. Colonel James Bourland, Lieutenant Colonel John R. Diamond, and Major Charles L. Roff were in command.
Battles,
Elm Creek (October 13, 1864)
I hope this is of some help to you,
Gary D. Bray