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="Canadian_Event" />
  </query-continue>
  <query>
    <pages>
      <page ns="10" title="Template:Canadian Business" missing="" />
      <page pageid="1805" ns="10" title="Template:Browse Canadian" />
      <page pageid="2573" ns="10" title="Template:CGG3OCUDestination" />
      <page pageid="2245" ns="10" title="Template:Canadian Building" />
      <page pageid="2267" ns="10" title="Template:Canadian Community" />
      <page pageid="2275" ns="10" title="Template:Canadian Document" />
      <page pageid="2284" ns="10" title="Template:Canadian Dream" />
      <page pageid="2285" ns="10" title="Template:Canadian Economy" />
      <page pageid="2287" ns="10" title="Template:Canadian Education" />
      <page pageid="2286" ns="10" title="Template:Canadian Environment" />
    </pages>
  </query>
</api>