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="Company|164" />
  </query-continue>
  <query>
    <pages>
      <page pageid="89" ns="0" title="Bevingtons and Sons Limited" />
      <page pageid="15" ns="0" title="John Knight&#039;s Soap" />
      <page pageid="139" ns="0" title="Henry Tate &amp; Sons" />
      <page pageid="124" ns="0" title="Price&#039;s Patent Candle Company" />
      <page pageid="163" ns="0" title="British Tyre and Rubber Co" />
      <page pageid="159" ns="0" title="S. Bowley and Son" />
      <page pageid="162" ns="0" title="India Rubber, Gutta Percha and Telegraph Works Company" />
      <page pageid="157" ns="0" title="Royal Doulton" />
      <page pageid="65" ns="0" title="Gas Light &amp; Coke Company" />
      <page pageid="155" ns="0" title="Imperial Gas Light &amp; Coke Company" />
    </pages>
  </query>
</api>