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="20150526075508" timestamp="2015-05-26T07:55:08Z" ns="0" title="Sandbox" />
        <page value="20150627010402" timestamp="2015-06-27T01:04:02Z" ns="0" title="about" />
        <page value="20150627011116" timestamp="2015-06-27T01:11:16Z" ns="0" title="管理者情報" />
        <page value="20161016034240" timestamp="2016-10-16T03:42:40Z" ns="0" title="Linux関連/sshdをtcpserver経由で動かす" />
        <page value="20161104125853" timestamp="2016-11-04T12:58:53Z" ns="0" title="Linux関連/DHCPサーバーの設定" />
        <page value="20161105032202" timestamp="2016-11-05T03:22:02Z" ns="0" title="Linux関連/Asterisk(ひかり電話対応)の設定" />
        <page value="20161117035130" timestamp="2016-11-17T03:51:30Z" ns="0" title="Linux関連/WebDAVの設定" />
        <page value="20180904015957" timestamp="2018-09-04T01:59:57Z" ns="0" title="Linux関連/gitlabのセットアップ" />
        <page value="20180912132313" timestamp="2018-09-12T13:23:13Z" ns="0" title="Linux関連" />
        <page value="20180919133221" timestamp="2018-09-19T13:32:21Z" ns="0" title="Linux関連/tinydnsを使う" />
      </results>
    </querypage>
  </query>
</api>