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>
    <allimages gaicontinue="Ancona_for_chart.png" />
  </query-continue>
  <query>
    <pages>
      <page pageid="512" ns="6" title="File:102 Best Araucan Btm male Simons.png" />
      <page pageid="513" ns="6" title="File:107 Ch Naked Neck Olive.png" />
      <page pageid="514" ns="6" title="File:116 Best Silver Sebright male Maudsley.png" />
      <page pageid="542" ns="6" title="File:2006 Annual Show de Watermael Opposite Sex 4.png" />
      <page pageid="507" ns="6" title="File:40 chwelsummer keogh.png" />
      <page pageid="518" ns="6" title="File:72 chsilvspanghamburgh balch.png" />
      <page pageid="15" ns="6" title="File:American game.jpg" />
      <page pageid="446" ns="6" title="File:American game1.png" />
      <page pageid="14" ns="6" title="File:Ancona chick head.JPG" />
      <page pageid="13" ns="6" title="File:Ancona cock.jpg" />
    </pages>
  </query>
</api>