var IndexBehavior = Class.create();

IndexBehavior.Apply = function() {

	var tract = $('tractindex');
	var tractcaption = $('tractindex').down('.caption');;
	
	Element.addClassName(tractcaption, 'hide');
	
	tractcaption.setOpacity(.6);
	
	tract.onmouseover = function() {
		Element.removeClassName(tractcaption, 'hide');
	}
	tract.onmouseout = function() {
		Element.addClassName(tractcaption, 'hide');
	}
	
}