\begin{table}%t1
\par
\caption{Surveyed clusters.
\label{tab1}}
%\centerline
 {\begin{tabular}{lrrrrrrrrrrrr} 
\hline\hline
Cluster & \multicolumn{6}{c}{Cluster centre} & \multicolumn{1}{c}{${r}_{\rm A}$} &
\multicolumn{2}{c}{ ${r}_{\rm vir}$ } & 
\multicolumn{1}{c}{ $z_{o}^{\dagger}$ } &
\multicolumn{1}{c}{ $\sigma_{v}^{\dagger}$ } & \multicolumn{1}{c}{$n^{\dagger}$} \\ \cline{2-7} \cline{9-10}
 & \multicolumn{4}{c}{RA (1950) Dec.} & \multicolumn{1}{c}{$l$} &
\multicolumn{1}{c}{$b$} & \multicolumn{1}{c}{(arcmin)} & 
\multicolumn{1}{c}{(Mpc)} & \multicolumn{1}{c}{(${r}_{\rm A}$)} &&
\multicolumn{1}{c}{(km ${\rm s}^{-1}$)} & \\ \hline 
 Abell 262  & 
 1$^{\rm h}$ \hspace{-0.85em} &
 49\fm9 \hspace{-0.75em} &
 35$^{\circ}$ \hspace{-0.85em} &
 54$^{\prime}$ \hspace{-0.65em} &
 136\fdg59 \hspace{-0.50em} &
 --25\fdg09 \hspace{-0.50em} &      105 \hspace{0.70em} & 1.83 & 0.86 &     0.0167&    
537 \hspace{0.60em}   &    38 \\ 
 Abell 347  &    2& 22.7&    41& 39&   141.17&--17.63&       91 \hspace{0.70em} & 1.87 & 0.87 &     0.0192&    
550 \hspace{0.60em}  &    14 \\                                         
 Abell 400  &    2& 55.0&     5& 50&   170.25&--44.93&       72 \hspace{0.70em} & 1.32 & 0.62 &     0.0227&    
392 \hspace{0.60em}  &    10 \\  
 Abell 426  &    3& 15.3&    41& 20&   150.39&--13.38&       96 \hspace{0.70em} & 3.67 & 1.72 &     0.0177&   
1076 \hspace{0.60em} &   55 \\                                         
 Abell 569  &    7&  5.4&    48& 42&   168.58& 22.81&       88 \hspace{0.70em} & 1.42 & 0.66 &     0.0198&    
417 \hspace{0.60em}  &    26 \\                                         
 Abell 779  &    9& 16.8&    33& 59&   191.07& 44.41&       75 \hspace{0.70em} & 0.98 & 0.46 &     0.0232&    
290 \hspace{0.60em}  &    11 \\
 Abell 1367 &   11& 41.9&    20&  7&   234.81& 73.03&       80 \hspace{0.70em} & 2.58 & 1.21 &     0.0216&    
762 \hspace{0.60em}  &    62 \\                                         
 Abell 1656 &   12& 57.4&    28& 15&    58.09& 87.96&       74 \hspace{0.70em} & 3.01 & 1.41 &     0.0232&    
890 \hspace{0.60em}  &   131 \\ \hline
\end{tabular}}
\par
\smallskip
$^{\dagger}$ E--S0/a galaxies only.
Cluster centres are taken from Abell et~al.  (\cite{Abell89}). The
Abell radius (Abell \cite{Abell58}), ${r}_{\rm A}$, corresponds to $\sim $$1.5~
h^{-1}$~Mpc. Values for the virial radius, ${r}_{\rm vir}$, are
from Moss (\cite{Moss06}), where $h=0.75$ is assumed. Cluster mean redshifts,
$z_{0}$, and velocity dispersions, $\sigma_{\rm v}$, are based on 
$n$~redshifts of galaxies of types E--S0/a only. These objects are more likely to be in dynamic equilibrium with the cluster potential and follow a Gaussian distribution, as expected for virially relaxed galaxies within the cluster (see Moss \cite{Moss06}).  The mean
redshift has been corrected to the centroid of the Local Group
following~RC2 (de~Vaucouleurs et~al.  \cite{deVaucouleurs76}).
\end{table}