  An experimentally verifiable Higgs-triplet model of neutrino masses from
large extra dimensions was recently proposed. We extend it to accomodate a
light sterile neutrino which also mixes with the three active neutrinos. A
previously proposed phenomenological model of four neutrinos (\underline {the
only viable such model now left}, in view of the latest atmospheric and solar
neutrino-oscillation data) is specifically realized.
