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="11_Contagious_PresentForYou.jpg" />
  </query-continue>
  <query>
    <pages>
      <page pageid="1275" ns="6" title="File:01 Contagious SpankySpoon.jpg" />
      <page pageid="1276" ns="6" title="File:02 Contagious BlueTriangleBarbie.jpg" />
      <page pageid="1277" ns="6" title="File:03 Contagious GetTested.jpg" />
      <page pageid="1278" ns="6" title="File:04 Contagious NotTheBoss.jpg" />
      <page pageid="1279" ns="6" title="File:05 Contagious 20Bucks.jpg" />
      <page pageid="1280" ns="6" title="File:06 Contagious OptionNumberFour.jpg" />
      <page pageid="1281" ns="6" title="File:07 Contagious MadeOfMean.jpg" />
      <page pageid="1282" ns="6" title="File:08 Contagious TrafficControl.jpg" />
      <page pageid="1283" ns="6" title="File:09 Contagious HelpYou.jpg" />
      <page pageid="1284" ns="6" title="File:10 Contagious NumbersUp.jpg" />
    </pages>
  </query>
</api>