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>
    <querypage qpoffset="10" />
  </query-continue>
  <query>
    <querypage name="Ancientpages">
      <results>
        <page value="20140818133523" timestamp="2014-08-18T13:35:23Z" ns="0" title="$contents" />
        <page value="20140829042514" timestamp="2014-08-29T04:25:14Z" ns="0" title="サイアミン欠乏" />
        <page value="20140829073824" timestamp="2014-08-29T07:38:24Z" ns="0" title="マークアップ早見" />
        <page value="20140916143536" timestamp="2014-09-16T14:35:36Z" ns="0" title="ウイルス性出血熱" />
        <page value="20140918061124" timestamp="2014-09-18T06:11:24Z" ns="0" title="掻痒" />
        <page value="20140919055111" timestamp="2014-09-19T05:51:11Z" ns="0" title="Geshtalt:vetwiki参考リンク" />
        <page value="20141012084033" timestamp="2014-10-12T08:40:33Z" ns="0" title="低アルブミン血症" />
        <page value="20141029071048" timestamp="2014-10-29T07:10:48Z" ns="0" title="エチレングリコール" />
        <page value="20141107103455" timestamp="2014-11-07T10:34:55Z" ns="0" title="股関節脱臼" />
        <page value="20141109170803" timestamp="2014-11-09T17:08:03Z" ns="0" title="性成熟と性周期" />
      </results>
    </querypage>
  </query>
</api>