The hints of vivid red visible through fissures in the gray paint in this photo of the lower left corner of Untitled (ca. 1955) reveal the presence of an underlying painting. Rauschenberg frequently reused canvases and other materials, particularly in the 1950s, when he was short on resources. Untitled (ca. 1955) is painted on top of an unidentified work from Rauschenberg’s Red Paintings, a series of monochromatic works with heavily collaged, painted surfaces that he created in 1953 and 1954. Rauschenberg transformed the original painting into Untitled (ca. 1955) by adding new collage elements to some areas of the composition and covering others with gray paint.