JQuery :: Selecting A Li Element By The Name Of The Image It Contains?

How do I select an element based upon the text in a variable?

Here's the basic HTML

<ul id="pictures">
<li><img src="images/ernst/01_aelpler_maccaroni.gif" />Älpler-Maccaroni</li>
<li><img src="images/ernst/02_hoernli_mittel.gif" />Hörnli mittel</li>
<ul>

I want to show and hide the <li> Element. thought i'd do this by applying a css-class to the element

Here's what I came up with so far:

$(".download_liste li a").click(function() {
var showPic = $(this).attr("href");
$("[name*="showPic"]").next.toggleClass("hiddenpic");});
});

Well, it doesn't work, anybody care to tell me why? Or am i way off?