  We show that various actions of topological conformal theories that were
suggested recentely are particular cases of a general action. We prove the
invariance of these models under transformations generated by nilpotent
fermionic generators of arbitrary conformal dimension, $\Q$ and $\G$. The later
are shown to be the $n^{th}$ covariant derivative with respect to ``flat
abelian gauge field" of the fermionic fields of those models. We derive the
bosonic counterparts $\W$ and $\R$ which together with $\Q$ and $\G$ form a
special $N=2$ super $W_\infty$ algebra. The algebraic structure is discussed
and it is shown that it generalizes the so called ``topological algebra".
