High-resolution echelle spectra that were obtained with the l-m Specia
l Astrophysical Observatory telescope (Russian Academy of Sciences) ar
e used to determine the abundances of Li and CNO in the atmospheres of
nine peculiar giants (eight CN-strong stars and the SMR star 31 Aql)
by the method of model atmospheres. The derived Li and CNO abundances
relative to the iron abundance are close to the mean values for disk G
-K giants and suggest that the stars under consideration have gone thr
ough the mixing phase (the first dredge-up). For the CN-strong stars,
the C/O ratios imply a slight carbon overabundance in their atmosphere
s, but it is unlikely to be evidence for the hypothesis of Keenan and
Heck (1994) that the CN-strong stars could be marginal R stars.