  We have conducted a study of optical and HI properties of spiral galaxies
(size, luminosity, H-alpha flux distribution, circular velocity, HI gas mass)
to investigate causes (e.g., nature versus nurture) for variation within the
cluster environment. We find HI deficient cluster galaxies to be offset in
Fundamental Plane space, with disk scale lengths decreased by a factor of 25%.
This may be a relic of early galaxy formation, caused by the disk coalescing
out of a smaller, denser halo (e.g., higher concentration index) or by
truncation of the hot gas envelope due to the enhanced local density of
neighbors, though we cannot completely rule out the effect of the gas stripping
process. The spatial extent of H-alpha flux and the B-band radius also
decreases, but only in early type spirals, suggesting that gas removal is less
efficient within steeper potential wells (or that stripped late type spirals
are quickly rendered unrecognizable). We find no significant trend in stellar
mass-to-light ratios or circular velocities with HI gas content, morphological
type, or clustercentric radius, for star forming spiral galaxies throughout the
clusters. These data support the findings of a companion paper that gas
stripping promotes a rapid truncation of star formation across the disk, and
could be interpreted as weak support for dark matter domination over baryons in
the inner regions of spiral galaxies.
