function show_country(){

	  var v_coun = document.search_form.Councod.length-1;
	  for(var i=0;i<v_coun;i++){
		  document.search_form.Councod.options[0] = null;
	   }
		if (document.search_form.continent.value==""){
			 document.search_form.Councod.options[0].value="";		 
			 document.search_form.Councod.options[0].text="---请选择---";
		}else{
		  var v_range = document.search_form.continent.value;
		  var j = counname[v_range].length;
		  for(var i=0;i<j;i++)

		   {document.search_form.Councod.options[i] = new Option(counname[v_range][i],councod[v_range][i]);
		   }
		}  
		return;
 }