d3.xml()

d3.xml(url[, callback])

Creates a request for the XML file at the specified url with the default mime type application/xml.

This convenience constructor is approximately equivalent to:

d3.request(url)
    .mimeType("application/xml")
    .response(function(xhr) { return xhr.responseXML; })
    .get(callback);

XML parsing relies on xhr.responseXML which is not supported by node-XMLHttpRequest as of version 1.8; thus, this method is supported in browsers but not in Node.