This paper summarizes the evidence of the ultraviolet properties of dust
grains found in starburst galaxies. Observations of starburst galaxies clearly
show that the 2175 A feature is weak or absent. This can be the result of
radiative transfer effects (mixing the dust and stars) or due to dust grains
which do not have this feature. Spherical DIRTY radiative transfer models imply
that it is not radiative transfer effects, but other radiative transfer models
with disk/bulge geometries have found cases where it could be radiative
transfer effects. Recent work on the extinction curves in the Magellanic Clouds
and Milky Way has revealed that the traditional explanation of low metallicity
for the absence of the 2175 A feature in the Small Magellanic Cloud is likely
incorrect. The SMC has one sightline with a 2175 A feature and the Milky Way
has sightlines without this feature. In addition, where the 2175 A feature is
found to be weak or absent in both Magellanic Clouds and the Milky Way, there
is evidence for recent star formation. Taking the sum of the radiative transfer
modeling of starburst galaxies and the behavior of Local Group extinction
curves, it is likely that the dust grains in starburst galaxies intrinsically
lack the 2175 A feature.Comment: 7 pages, To appear in the proceedings of: "The Spectral Energy
Distribution of Gas-Rich Galaxies: Confronting Models with Data", Heidelberg,
4-8 Oct. 2004, eds. C.C. Popescu and R.J. Tuffs, AIP Conf. Ser., in press
[fixed typo in title
