  Consider an infinite-dimensional linear space equipped with a Gaussian
measure and the group $GL(\infty)$ of linear transformations that send the
measure to equivalent one. Limit points of $GL(\infty)$ can be regarded as
'spreading' maps (polymorphisms). We show that the closure of $GL(\infty)$ in
the semigroup of polymorphisms contains a certain semigroup of operator
colligations and write explicit formulas for action of operator colligations by
polymorphisms of the space with Gaussian measure.
