  We present alpha to iron abundance ratios for 226 individual red giant branch
stars in nine dwarf galaxies of the Andromeda (M 31) satellite system. The
abundances are measured from the combined signal of Mg, Si, Ca, and Ti lines in
Keck/DEIMOS medium-resolution spectra. This constitutes the first large sample
of alpha abundance ratios measured in the M 31 satellite system. The dwarf
galaxies in our sample exhibit a variety of alpha abundance ratios, with the
average values in each galaxy ranging from approximately solar ([alpha/Fe] ~
+0.0) to alpha-enhanced ([alpha/Fe] ~ +0.5). These variations do not show a
correlation with internal kinematics, environment, or stellar density. We
confirm radial gradients in the iron abundance of two galaxies out of the five
with sufficient data (NGC 185 and And II). There is only tentative evidence for
an alpha abundance radial gradient in NGC 185. We homogeneously compare our
results to the Milky Way classical dwarf spheroidals, finding evidence for
wider variation in average alpha abundance. In the absence of chemical
abundances for the M 31 stellar halo, we compare to the Milky Way stellar halo.
A stellar halo comprised of disrupted M31 satellites is too metal-rich and
inconsistent with the Milky Way halo alpha abundance distribution even if
considering only satellites with predominantly old stellar populations. The M
31 satellite population provides a second system in which to study chemical
abundances of dwarf galaxies and reveals a wider variety of abundance patterns
than the Milky Way.
