SOURCE

 //公告滚动
            var infoNews = function(delay) {
                var $info = $('.info-index'),
                    $ul = $info.find('ul');
                delay = delay || 4000;
                if($info.find('li').length <= 1)
                    return;
                setTimeout(function() {
                    $ul.animate({
                        left: -60
                    }, 500, function() {
                        var first = $info.find('li')[0];
                        $ul[0].appendChild(first);
                        $ul.css({
                            top: 0
                        });
                    });
                    setTimeout(arguments.callee, delay);
                }, delay);
            };
            infoNews();

<div class="info-index">
            <ul>
                <li>sadaaaaaaaaaaaaaaaaaaaa</li>
                <li>111111111111111111111111111</li>
                <li>dddddddddddddddddddddddddddd</li>
                <li>kkkkkkkkkkkkkkkkkkkkkkkkkk</li>
                <li>sadaaaaaaaaaaaaaaaaaaaa</li>
                <li>rrrrrrrrrrrrrrrrrrrrrrrrr</li>
                <li>tttttttttttttttttttttttt</li>
                <li>gggggggggggggg</li>

            </ul>
        </div>