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>
    <pages>
      <page pageid="4" ns="0" title="ACKNOWLEDGEMENTS" contentmodel="wikitext" pagelanguage="en-ca" touched="2015-09-01T03:43:19Z" lastrevid="5" counter="" length="1837" new="" />
      <page pageid="5" ns="0" title="CONTACTS" contentmodel="wikitext" pagelanguage="en-ca" touched="2015-09-01T03:43:19Z" lastrevid="6" counter="" length="585" new="" />
      <page pageid="6" ns="0" title="Fensome and Williams, 2004" contentmodel="wikitext" pagelanguage="en-ca" touched="2015-09-01T03:48:34Z" lastrevid="7" counter="" length="222" new="" />
      <page pageid="683" ns="0" title="Fensome et al., 1993b" contentmodel="wikitext" pagelanguage="en-ca" touched="2015-09-01T03:48:34Z" lastrevid="684" counter="" length="328" new="" />
      <page pageid="3" ns="0" title="HOW IT WORKS" contentmodel="wikitext" pagelanguage="en-ca" touched="2015-09-01T03:43:19Z" lastrevid="4" counter="" length="4304" new="" />
      <page pageid="1148" ns="0" title="Kofoid and Skogsberg, 1928" contentmodel="wikitext" pagelanguage="en-ca" touched="2015-09-01T03:48:34Z" lastrevid="1149" counter="" length="208" new="" />
      <page pageid="14939" ns="0" title="PDF document" contentmodel="wikitext" pagelanguage="en-ca" touched="2015-09-08T12:35:27Z" lastrevid="14950" counter="" length="1431" new="" />
      <page pageid="2" ns="0" title="USING DINOFLAJ2" contentmodel="wikitext" pagelanguage="en-ca" touched="2015-09-08T22:16:43Z" lastrevid="3" counter="" length="4742" new="" />
    </pages>
  </query>
</api>