ABUNDANCE ANALYSES OF FIELD RV TAURI VARIABLES .3. DY AQUILAE, SS GEMINORUM, CT ORIONIS, AND CE VIRGINIS

Analyses of the photospheric compositions of the four field RV Tauri s tars, DY Aql, SS Gem, CT Ori, and CE Vir, indicate that to varying deg rees they have experienced fractionation processes that have preferent ially depleted their atmospheres of elements with high condensation te mperatures. This corroborates our previous studies, which showed simil ar patterns in five other field RV Tauri stars. Two stars in our sampl e, DY Aql and CE Vir, were found to have strong Li I resonance lines, with corresponding lithium abundances near log epsilon(Li)= 0.0; this is not significantly different from that found in less evolved M giant s. These are also the coolest stars displaying a correlation of photos pheric abundances with condensation temperatures.