Using Ajax to append image source

In my HTML document I have a div with id='storefrontimg'. In my XML document I have:

<storefrontpicture>imagename.png</storefrontpicture>

In my success function after ajax loads the XML file, I have:

$("#storefrontimg").append("<img src='_images/" + $(xml).find("storefrontpicture").text() + "/>");

But nothing is happening, not even a broken filepath image where the picture should be. This is all incredibly simple so am I missing some key concept?