\begin{table}%t2
\caption{\label{tab2}Densities and porosities of meteoroids.}
\small%\centerline
 {
 \begin{tabular}{l|l|cc|cc|cc|c}
\hline\hline
%&&&&&&&& \\[-8pt]
Meteor&Parent& $\delta_{\rm m}$, g~cm$^{-3}$ & $N_{\rm m}$ &$\delta_{\rm m}$, g~cm$^{-3}$ & $N_{\rm m}$ & $\delta$, g~cm$^{-3}$& $N_{\rm b}$ & $p$,\\
      stream&body&\multicolumn{2}{|c|}{Benyuch (\cite{benyuch74})}&\multicolumn{2}{|c|}{This ~ work}&\multicolumn{2}{|c|}{This ~ work}&$\%$\\
  \hline
Draconids&21P/Giacobini-Zinner&1.8&175&$-$&$-$&0.3$^{**}$&$-$&83\\
Leonids&55P/Tempel-Tutlle&$-$&$-$&$2.3\pm 0.2$&10&$0.4\pm 0.1$&6&83\\
Orionids&1P/Halley&$-$&$-$&$2.4\pm 0.2$&6&$0.9\pm 0.5$&2&62\\
Perseids&109P/Swift-Tutlle&2.4&309&$2.25\pm 0.04$&191&$1.2\pm 0.2$&97&45\\
Taurids&2P/Encke&2.7&63&$2.7\pm 0.2$&12&$1.6\pm 0.4$&6&41\\
Quadrantids&2003EH1 ~and  ~96P/Machholz1&3.4&20&$3.4\pm 0.8$&4&$1.9\pm 0.2$&3&44\\
$\alpha$-Capricornids&2003EX12 = 169P/NEAT&2.8&34&$3.4\pm 0.8$&5&2.1&1&38\\
$\kappa$-Cygnids&2008ED69?&$-$&$-$&$2.5\pm 0.1$&2&$2.2\pm 1.7$&2&12\\
$\delta$-Aquarids&2003EH1 ~and  ~96P/Machholz1&4.1&36&$3.4\pm 0.4$&13&$2.4\pm 0.6$&8&29\\
Geminids&3200 Phaethon&3.3&118&$2.9\pm 0.2$&20&$2.9\pm 0.6$&8&0\\
Sporadic&&2.7&2267&$3.0\pm 0.1$&238&$1.8\pm 0.3$&103&40\\
\hline
\end{tabular}}
\medskip
$^{**}$ The value of the bulk density is taken from Borovi\v cka et~al. (\cite{borovicka07}).
\end{table}