We present the results of a variable star search in Andromeda II , a dwarf spheroidal galaxy companion to M31 , using Hubble Space Telescope 
Wide Field Planetary Camera 2 observations .
Seventy-three variables were found , one of which is an anomalous Cepheid while the others are RR Lyrae stars .
The anomalous Cepheid has properties consistent with those found in other dwarf spheroidal galaxies .
For the RR Lyrae stars , the mean periods are 0.571 day and 0.363 day for the fundamental mode and first-overtone mode stars , respectively .
With this fundamental mode mean period and the mean metallicity determined from the red giant branch ( \langle { [ Fe / H ] } \rangle = -1.49 ) , Andromeda II follows the period-metallicity relation defined by the Galactic globular clusters and other dwarf spheroidal galaxies .
We also find that the properties of the RR Lyrae stars themselves indicate a mean abundance that is consistent with that determined from the red giants .
There is , however , a significant spread among the RR Lyrae stars in the period-amplitude diagram , which is possibly related to the metallicity spread in Andromeda II indicated by the width of the red giant branch in Da Costa et al .
In addition , the abundance distribution of the RR Lyrae stars is notably wider than the distribution expected from the abundance determination errors alone .
The mean magnitude of the RR Lyrae stars , \langle V _ { RR } \rangle = 24.87 \pm 0.03 , implies a distance d = 665 \pm 20 kpc to Andromeda II .
This matches the distance derived from the mean magnitude of the horizontal branch stars by Da Costa et al. , d = 680 \pm 20 kpc .
We also demonstrate that the specific frequency of anomalous Cepheids in dwarf spheroidal galaxies correlates with the mean metallicity of their parent galaxy , and that the Andromeda II and Andromeda VI anomalous Cepheids appear to follow the same relation as those in the Galactic dwarf spheroidals .