  We have studied the Ly-al, Hbeta, Halpha and Mg II2798 line profiles of the
Seyfert 1 galaxy III Zw 2. The shapes of these broad emission lines show
evidence of a multicomponent origin and also features which may be identified
as the peaks due to a rotating disk. We have proposed a two-component Broad
Line Region (BLR) model consisting of an inner Keplerian relativistic disk and
an outer structure surrounding the disk. The results of the fitting of the four
Broad Emission Lines (BELs) here considered, are highly consistent in both the
inner and outer component parameters. Adopting a mass of approx. 2 E8 sollar
masses for the central object we found that the outer radius of the disk is
approximately equal for the four considered lines (approx 0.01 pc). However,
the inner radius of the disk is not the same: 0.0018 pc for Ly-alpha, 0.0027 pc
for Mg II, and 0.0038 pc for the Balmer lines. This as well as the relatively
broad component present in the blue wings of the narrow [OIII] lines indicate
stratification in the emission-line region. Using long-term Hbeta observations
(1972-1990, 1998) we found a flux variation of the BEL with respect to the
[OIII] lines.
