  In a paper by Michaelis a class of infinite-dimensional Lie bialgebras
containing the Virasoro algebra was presented. This type of Lie bialgebras was
classified by Ng and Taft. In this paper, all Lie bialgebra structures on the
Lie algebras of generalized Witt type are classified. It is proved that, for
any Lie algebra $W$ of generalized Witt type, all Lie bialgebras on $W$ are
coboundary triangular Lie bialgebras. As a by-product, it is also proved that
the first cohomology group $H^1(W,W \otimes W)$ is trivial.
