  We investigate the degree distribution $P(k)$ and the clustering coefficient
$C$ of the line graphs constructed on the Erd\"os-R\'enyi networks, the
exponential and the scale-free growing networks. We show that the character of
the degree distribution in these graphs remains Poissonian, exponential and
power law, respectively, i.e. the same as in the original networks. When the
mean degree $<k>$ increases, the obtained clustering coefficient $C$ tends to
0.50 for the transformed Erd\"os-R\'enyi networks, to 0.53 for the transformed
exponential networks and to 0.61 for the transformed scale-free networks. These
results are close to theoretical values, obtained with the model assumption
that the degree-degree correlations in the initial networks are negligible.
