  Frequencies of 13 oscillation modes in the star XX Pyxidis (CD-24 7599) are
accurately measured but for none of the modes the spherical harmonic degree l
is known. We present results of an attempt to construct the model whose low-l
mode frequencies reproduce possibly close the observations. Models are
constrained by the mean photometric and spectroscopic data for the star.
However, the strongest constraint on the effective temperture is from the
requirement that the modes excited in the star fall into the range of the modes
driven by the opacity mechanism.
  Our models are built with the standard stellar evolution code allowing no
overshooting from the convective core. Effects of rotation are taken into
account both in stellar evolution and in linear nonadiabatic oscillation
calculations. Uniform rotation rate and conservation of the global angular
momentum during evolution are assumed.
  We find several distinct mode identifications and associated stellar models
leading to frequency fits of similar quality. Determination of the l values for
some of the modes could remove the ambiguity. None of the fits is satifactory:
the mean departures exceed the mean observational frequency error by at least
one order of magnitude. The fits could be improved by means of adjusting model
parameters that were kept fixed. However, such effort will be meaningful only
after improving accuracy in calculation of the effects of rotation in
oscillation frequencies.
