Cathay Williams was the only female Buffalo Soldier. At this time women weren't allowed to be a part of the Buffalo soldiers so she posed as a man by changing her name to William Cathay. She joined the thirty-eighth infantry in November of 1866. On October 14, 1868 she faked an illness and upon examination she was found to be female and was promptly discharged. This made her known as the only female soldier.

http://www.ncbuffalosoldiers.org/history.asp?u_action=display&u_log=1

Late 1800's photograph of members of the 10th Cavalry (Buffalo Soldiers). Augustus Walley (top row, 2nd from right, with the bandana around his neck), a former slave from Bond Avenue in Reisterstown, MD, won the Congressional Medal of Honor

http://www.operationmorningstar.org/

This is a photograph of the 24th Mounted Infantry taken somewhere in Yosemite in 1899.

http://americanindiansource.com/buffalosoldiers/BuffaloSoldiersInCalifornia.html