It could be the 4th Missouri Cavalry, USA, Colonel George E. Waring, Jr. I could not find any mention of the loss of colors in the OR or other literature.

Numbers 5. Report of Colonel Embury D. Osband, Third U. S. Colored Cavalry, commanding Third Cavalry Brigade.

. . . . On the 28th I sent, as ordered, six companies of the Second Wisconsin Cavalry, under Major William Woods, to hold Pikeville. Nearing Egypt Station the column was closed up, and the skirmishing of the First Brigade becoming exceedingly warm, the pack train in my front being in confusion, blocking up the road, I took the field with the Fourth and Eleventh Illinois Cavalry and Third U. S. Colored Cavalry, leaving six companies of the Second Wisconsin Cavalry, under Captain N. DeForest, to guard brigade pack train and prisoners. Moving rapidly toward the scene of the engagement I was ordered by Colonel Karge to support his right flank, held by the Fourth Missouri Cavalry, who were carrying on a fight with Brigadier-General Gholson's command, who were inflicting great loss to the Fourth Missouri Cavalry from the shelter of a railroad embankment, without danger to themselves. Without firing one shot the Fourth Illinois Cavalry, having formed line on the right of the Fourth Missouri Cavalry,”* charged, utterly routing Gholson and pursuing his flying squadrons to the road beyond. The revolver and saber were feebly used by our men, 15 or 20 of the enemy being either killed or wounded, including Brigadier-General Gholson, mortally wounded; 1 lieutenant-colonel, 5 line officers, and 10 enlisted men were captured. In this brilliant attack we lost 2 men severely wounded; the enemy, their killed, wounded, and prisoners, the total rout and dispersion of their entire cavalry force, had their left turned, and the retreat to the swamp, before this open to the garrison of the stockade, entirely and permanently cut off. . . . OR V45 Pt. 1 p. 857

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Numbers 2. Report of Colonel Joseph Kerge, Second New Jersey Cavalry, commanding First Cavalry Brigade.

HEADQUARTERS FIRST BRIGADE, CAVALRY DIVISION,
Camp Karge, January 12, 1865.

SIR: I have the honor to forward their official report of the proceedings of my brigade during the expedition into Mississippi under Brigadier General B. H. Grierson.

. . . . Moved at 8 o'clock a. m. on the 27th on the I Okolona road; halted at Okolona, and resumed the march at 3 o'clock; camped on the West Point road at 5 o'clock, four miles fourth of Okolona. District marched, twenty miles. During the night men of the enemy came into my pickets and gave themselves up as deserters. On the 28th of December marched at 7 o'clock, in the advance, on the West Point road. When within two miles of Egypt I met the enemy's cavalry; drove them, and soon came upon their skirmish line. Within half a mile of Egypt Station I found the enemy in a strong position. I ordered a charge through their skirmish line, which was executed. The impetuosity of the charge of the Second New Jersey Cavalry was so great that their skirmish line was at once driven in. Captain Gallagher, Company H, Second New Jersey Cavalry, commanding the First Battalion, broke the center, and in endeavoring to pass their stockade was shot down at the head of his column. I formed in of battle in the following order: Second New Jersey Cavalry Lieutenant-Colonel Hencke, and Seventh Indiana Cavalry, Captain Elliott, on the right. The enemy made a very strongresistance, but I drove him back. I ordered Captain Elliott to take the Seventh Indiana Cavalry and Fourth Missouri Cavalry to capture a train, which was about to move of, and which annoyed my line by opening with shell and solid shot from a battery of four guns. When this order was about executed Brigadier General B. h. Grierson rode up and placed himself and the head of this detachment. I then left to watch the proceedings of the left and center. I found, after fighting, that Lieutenant-Colonel Yorke had carried out orders an was driving the enemy from his position. The rebels still had possession of a stockade on the east side of the railroad, upon which a charge was ordered. Two squadrons mounted charged the stockade on the left, and three companies dismounted, upon the right of it. Here such a galling fire was poured in upon the enemy that he surrendered. The number of prisoners taken in this stockade was 500, including 1 lieutenant-colonel and 15 line officers. About the time of the surrender of the stockade, Brigadier-General Gholson, commanding the rebel forces at Egypt, was mortally wounded by some of my command on their right flank. The loss in the Second new Jersey Cavalry was very heavy, that regiment having to bear the brunt of the battle. Officers, killed, 3; wounded, 2. Men killed, 16; wounded, 69. Total, killed and wounded, 90. On the right flank the Seventh Indiana Cavalry lost 2 killed and 11 wounded; the Fourth Missouri Cavalry, 1 officer captured, supported to be wounded, and 1 map wounded. Total, killed and wounded, 90. on the right flank the Seventh Indiana Cavalry lost 2 killed and 11 wounded; the Fourth Missouri Cavalry, 1 officer captured, supposed to be wounded, and 1 man wounded. Total loss in the brigade, 105 killed and wounded. The Seventh Indiana Cavalry captured 47 prisoners, including 1 lieutenant-colonel. Of the wounded, 1 officer and 39 men of the Second New Jersey Cavalry were left at Egypt, under the care of Doctor Krauter, assistant surgeon of the Second New Jersey Cavalry, their wounds being of such a serious nature as to prevent their removal. . . .

OR V45 Pt. 1, pp. 847-9