has the greatest filling factor with 0.78 amongst the six stars (see Table6). Excluding VZ CVn, the linear least-squares fit gives the following relationship,

$$log P_{puls} = -2.021(\pm 0.012) \times \log (F/M_{puls}) + 2.093(\pm 0.098)$$

with a correlation coefficient of 0.83. The high-value of the correlation coefficient indicates that this empirical relationship is very significant. As the force per unit mass on the surface of the pulsating star applied by the companion star is increased the pulsational period is decreased. The force exerted to per gram matter on the surface of the pulsating star can be calculated as,

$$\frac{F} {M_{puls}} = \frac{GM_{s}} {(a-R_{puls})^2}.$$

Since $P_{puls}$ $\propto$ $R_{puls}^{3/2}$ we can obtain $P_{puls}$ $\propto$ $(\frac{F}{M_{puls}})^{-3/4}$. As the gravitational pull exerted on the per gram matter of the pulsator is increased the pulsational period is decreased, confirming the empirical relationship found.

Even with a small sample, pulsation periods of the $\gamma$-Dor type pulsators in the close binaries seem to depend on the orbital periods of the systems, to the surface gravities of the pulsating primaries, and also to the gravitational pull applied by their companions. These empirical relationships should, of course, be checked by increasing the number of the sample.

Although we are 