How Different are Normal and Barred Spirals?
  No significant color differences are found between normal and barred spirals
over the range of Hubble stages a - ab - b - bc. Furthermore, no significant
difference is seen between the luminosity distributions of normal and barred
galaxies over the same range of Hubble stages. However, SBc galaxies are found
to be systematically fainter than Sc galaxies at 99% confidence. The
observation that normal and barred spirals with Hubble stages a - ab - b - bc
have indistinguishable intrinsic colors hints at the possibility that the bars
in such spiral galaxies might be ephemeral structures. Finally, it is pointed
out that lenticular galaxies of types S0 and SB0 are systematically fainter
than are other early-type galaxies, suggesting that such galaxies are situated
on evolutionary tracks that differ systematically from those of galaxies that
lie along the E - Sa - Sb -Sc and E - SBa - SBb - SBc sequences.
