Nonradial Oscillations of Stars.

In the first part of this paper a derivation is given of the Eulerian equations which govern the small and adiabatic oscillations of a general spherical harmonic type of non- rotating stars. These equations are then solved for a model of constant density. It is shown that with the exception of purely radial oscillations, which are unstable only when <~, there exist nonradial modes of oscillation, which are unstable for all values of y. The conclusion is drawn that in the pulsation theory of stellar variability it is necessary to consider nonradial disturbances in order to ascertain the possibility of the existence of any assumed model