  Gluon fusion into a very heavy neutrino pair by Higgs exchange is shown to
lead to substantial production cross sections at $pp$ supercolliders even
without any extra generation of quarks. Rates are calculated for scalar as well
as pseudoscalar Higgs. The angular correlation between dileptons emerging from
the decays of the neutrinos shows distinctive features for Dirac and Majorana
neutrinos as well as for scalar and pseudoscalar Higgs.
