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>
    <alltransclusions gatcontinue="High|215" />
  </query-continue>
  <query>
    <pages>
      <page pageid="16" ns="0" title="Rancourt and Company" />
      <page pageid="104" ns="3" title="User talk:Hip$ster" />
      <page pageid="107" ns="10" title="Template:CN" />
      <page pageid="184" ns="0" title="A.P.C." />
      <page pageid="211" ns="0" title="Stores In Belgium" />
      <page pageid="213" ns="0" title="Stores In Germany" />
      <page pageid="214" ns="0" title="Stores In The United Kingdom" />
      <page pageid="236" ns="10" title="Template:CategoryTOC" />
    </pages>
  </query>
</api>