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="20120803220652" timestamp="2012-08-03T22:06:52Z" ns="0" title="Production system" />
        <page value="20120909235803" timestamp="2012-09-09T23:58:03Z" ns="0" title="画像の補間" />
        <page value="20120912201043" timestamp="2012-09-12T20:10:43Z" ns="0" title="EosEnvSet" />
        <page value="20120917022540" timestamp="2012-09-17T02:25:40Z" ns="0" title="トモグラフィー" />
        <page value="20120924114253" timestamp="2012-09-24T11:42:53Z" ns="0" title="粒子抽出" />
        <page value="20121009111018" timestamp="2012-10-09T11:10:18Z" ns="0" title="開発にかける思いByYasunaga" />
        <page value="20121014091621" timestamp="2012-10-14T09:16:21Z" ns="0" title="後ろ向き連鎖" />
        <page value="20121014091822" timestamp="2012-10-14T09:18:22Z" ns="0" title="後ろ向き推論" />
        <page value="20121014092123" timestamp="2012-10-14T09:21:23Z" ns="0" title="前向き推論" />
        <page value="20121014180653" timestamp="2012-10-14T18:06:53Z" ns="0" title="Makeobj" />
      </results>
    </querypage>
  </query>
</api>