function showDesc(lnum){
	var snum = lnum.nextSibling;
	if ( document.getElementById(snum.nextSibling.id).className == 'childHidden'){
		document.getElementById(snum.nextSibling.id).className = 'childVisible';
		lnum.className = 'parentOn';
		}
	else{
		document.getElementById(snum.nextSibling.id).className = 'childHidden';
		lnum.className = 'parentOff';
		}
}