Statistical distribution of the neutral-hydrogen content of S0 galaxies

The distribution of relative global H I content M/sub HtsI//L/sub B/ has been derived for galaxies of types S0 and S0/a using a data set derived from recent H I observations in the literature. The relative H I content of these galaxies is found to show transitional properties between elliptical and spiral galaxies. The distribution of M/sub HtsI//L/sub B/ for S0/a's resembles that for spirals, and these galaxies may represent ''fossil'' spirals, i.e., galaxies whose gas has been severely depleted by star formation. The distribution for S0's, however, resembles that for ellipticals. The form of this distribution strongly suggests an external origin for most of the H I in S0 galaxies