This new minstrelsy maintained an emphasis on refined music. Most troupes added jubilees, or spirituals, to their repertoire in the 1870s. These were fairly authentic religious slave songs borrowed from traveling black singing groups. Other troupes drifted further from minstrelsy's roots. When George Primrose and Billy West broke with Haverly's Mastodons in 1877, they did away with blackface for all but the endmen and dressed themselves in lavish finery and powdered wigs. They decorated the stage with elaborate backdrops and performed no slapstick whatsoever. Their brand of minstrelsy differed from other entertainments only in name.