  We derive the 1-point probability density function of the smoothed 3-D
Abell-ACO cluster density field and we compare it with that of artificial
cluster samples, generated as high peaks of a Gaussian field in such a way that
they reproduce the low-order (2- and 3-point) correlation functions and the
observed cluster selection functions. We find that both real and simulated {\em
pdf}'s are well approximated by a log-normal distribution even when the
Gaussian smoothing radius is as large as 40 $h^{-1}$ Mpc. Furthermore the
low-order moments of the {\em pdf} are found to obey a relation $\gamma = S_{3}
\sigma^4$, with $\gamma$ being the skewness and $S_{3}\approx 1.8$. These
results are consistent with clusters being high-peaks of an underlying initial
Gaussian density field. A by-product of our analysis is that when we rescale
the {\em pdf} cluster moments to those of the QDOT-IRAS galaxies, using linear
biasing with $b_{cI}\sim 4.5$ and for the common smoothing radius of 20
$h^{-1}$ Mpc, we find them to be significantly smaller than those directly
estimated from the QDOT data by Saunders et al. (1991).
