  We have obtained low-dispersion spectra of NGC 3227 with the Space Telescope
Imaging Spectrograph (STIS) to study the intrinsic UV absorption and the
reddening of the nucleus in this Seyfert 1 galaxy. The UV spectra show a wealth
of absorption lines at the systemic redshift that span a wide range in
ionization state (Mg I to N V). The equivalent widths of the lines are
consistent with our earlier prediction that a ``lukewarm absorber'' (T= 18,000
K at the ionized face) with a substantial column of gas [N(H) = 2 x 10^21
cm^-2] is present and likely responsible for the reddening of the nucleus. The
lukewarm absorber is also responsible for most of the absorption in the X-rays
at energies less than 1 keV, although a more highly ionized ``warm absorber''
is needed to account for the O VII and O VIII ionization edges. In addition, we
require a small column [N(H) = 5 x 10^19 cm^-2] of cold gas to match the
strengths of the neutral and singly-ionized lines in the UV spectra. NGC 3227
is the first Seyfert galaxy in which a strong link between the reddening and
intrinsic UV absorption has been found. By comparing our STIS UV and optical
spectra with those of the unreddened Seyfert NGC 4151, we have determined a
reddening curve for the nuclear continuum source in NGC 3227 over the 1150 -
10,200 A range. The reddening curve does not show a 2200 AA bump, and is
steeper in the UV than reddening curves derived for the Galaxy, LMC, and SMC,
suggesting a preponderence of small dust grains near the nucleus.
