You are looking at the HTML representation of the XML format.
HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the XML format, set format=xml.
See the complete documentation, or API help for more information.
<?xml version="1.0"?>
<api>
  <query-continue>
    <allpages apcontinue="Birmingham_Museum_of_Fine_Art" />
  </query-continue>
  <query>
    <allpages>
      <p pageid="1497" ns="0" title="Baltimore Museum of Art" />
      <p pageid="1870" ns="0" title="Bangladesh National Museum" />
      <p pageid="1893" ns="0" title="Bankfield Museum" />
      <p pageid="1577" ns="0" title="Beamish Museum" />
      <p pageid="1927" ns="0" title="Beaufort West Museum" />
      <p pageid="1997" ns="0" title="Beaver County Historical Research &amp; Landmarks Foundation" />
      <p pageid="1865" ns="0" title="Beaver County Historical Research and Landmarks Foundation" />
      <p pageid="1649" ns="0" title="Benton County Museum" />
      <p pageid="1477" ns="0" title="Berks County Quilt Harvest" />
      <p pageid="1670" ns="0" title="Bernice P. Bishop Museum" />
    </allpages>
  </query>
</api>