\begin{table}%t2
\caption{\label{4:tab:obs}Overview of the APEX observations.}
%\centerline
 {\small\begin{tabular}{l l l l l}
\hline \hline\noalign{\smallskip}
Line & &Instrument & Cloud$^a$ & Note \\
\noalign{\smallskip}\hline
$^{12}$CO & 3--2 & APEX-2a & Cha, CrA, Iso. & \\
 & map & APEX-2a & Various & $80''\times80''$ \\
& 4--3 & FLASH-I & Cha, Iso & \\
& map & FLASH-I & Cha, Iso & $40''\times40''$\\
& 7--6 & FLASH-II & Cha, Iso &  \\
& map & FLASH-II & Cha, Iso & $40''\times40''$ \\
C$^{18}$O & 3--2 & APEX-2a & Cha, CrA, Iso. & \\
HCO$^+$ & 4--3 & APEX-2a & Cha, CrA, Iso. & \\
& map & APEX-2a &Various & $80''\times80''$ \\
H$^{13}$CO$^+$ &4--3 & APEX-2a & Cha, CrA, Iso. & \\
\hline
\end{tabular}}
\medskip
$^a$ Cha~=~Chamaeleon, CrA~=~Corona Australis and Iso. = Isolated sample.
\end{table}