\begin{table}%t12
\caption{Forbidden spectra in symbiotic stars.\label{tab12}}
%\centerline
{\begin{tabular}{llc} \hline\hline
Object     & Spectra & comm.                \\ \hline
Z And      & O I, N II, Mg V                                   &   \\
EG And     & O II, Ne III, Ar III                              & *  \\
R Aqr      & O II+III, Ar III                                  & *  \\
T CrB      &                                                   &   \\
BF Cyg     &                                                   &   \\ 
CH Cyg     & O II, Ar III                                      &   \\
CI Cyg     &                                                   &   \\
AG Dra     & Mg VI+VII                                         & *  \\
RW Hya     & O III, Ar IV                                      & *  \\
SY Mus     & Ar V, Mg V                                        &           \\
AG~Peg     & O III, Ne III+IV+V, Ar V, Mg V                    &           \\ 
AX Per     &                                                   &        \\
RX Pup     &                                                   &          \\
HM Sge     & O II, Ar IV, Ne IV, Mg V                          &           \\
RR Tel     & N II, O II+III, Ar III+IV+V, Ne III+IV+V, Mg V+VI &            \\ 
KX Tra     & Mg V+VI                                           & *  \\
PU Vul     &                                                   &        \\   
V1016 Cyg  & N II, O II+III, Ar IV, Ne IV, Mg V                &        \\
V1329 Cyg  &                                                   &          \\
HBV475     & Mg V                                              & *  \\ \hline
\end{tabular} }
\par
\smallskip
*  All forbidden lines in the system can be explaind by a low density region in local thermal equilibrium and of one
dominant temperature. 
\end{table}