nth-of-type

<div id="wrapper">
    <h1>context menu widget w/ menu plugin</h1>
    <!--BEGIN SOURCE CODE FOR EXAMPLE =============================== -->

    <div id="delegate" style="background: #ffeb88;">
        <div>first div</div>                                          
        <span>span confuses the universe</span> 
        <div>second div</div>                                         
        <div>third div</div>                                                                   
        <div>fourth div</div>                                           
    </div>
</div>
<script type="text/javascript">
YUI({
        base: 'js/yui3/build/',
        filter: 'raw'
    }).use("node", "selector-css3", function(Y) {                                                                     
        alert(Y.get('#delegate div:nth-of-type(2)').get('innerHTML'));
    }); 
</script>