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="20150519175823" timestamp="2015-05-19T17:58:23Z" ns="0" title="セキュリティ/暗号" />
        <page value="20150519175824" timestamp="2015-05-19T17:58:24Z" ns="0" title="Android/図形view" />
        <page value="20150519175824" timestamp="2015-05-19T17:58:24Z" ns="0" title="Android/FlashPlayer入手" />
        <page value="20150519175824" timestamp="2015-05-19T17:58:24Z" ns="0" title="Php/Smarty/セキュリティ" />
        <page value="20150519175825" timestamp="2015-05-19T17:58:25Z" ns="0" title="テストツール/selenium" />
        <page value="20150519175826" timestamp="2015-05-19T17:58:26Z" ns="0" title="Flash/基本" />
        <page value="20150519175826" timestamp="2015-05-19T17:58:26Z" ns="0" title="Php/zend framework/プロジェクトを作成せずに使用する" />
        <page value="20150519175827" timestamp="2015-05-19T17:58:27Z" ns="0" title="Php/zend framework/モバイル版作成" />
        <page value="20150519175827" timestamp="2015-05-19T17:58:27Z" ns="0" title="Android/画面の明るさ" />
        <page value="20150519175828" timestamp="2015-05-19T17:58:28Z" ns="0" title="Php/flash作成mingメモ" />
      </results>
    </querypage>
  </query>
</api>