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="20101230120906" timestamp="2010-12-30T12:09:06Z" ns="0" title="Main Page" />
        <page value="20101231152723" timestamp="2010-12-31T15:27:23Z" ns="0" title="The Library" />
        <page value="20101231160800" timestamp="2010-12-31T16:08:00Z" ns="0" title="Getting New Books" />
        <page value="20101231162427" timestamp="2010-12-31T16:24:27Z" ns="0" title="Renaming &amp; Deleting Books" />
        <page value="20110101041900" timestamp="2011-01-01T04:19:00Z" ns="0" title="Harry Potter Trailer" />
        <page value="20110101152527" timestamp="2011-01-01T15:25:27Z" ns="0" title="Global Subways and Metros" />
        <page value="20110101154356" timestamp="2011-01-01T15:43:56Z" ns="0" title="Sample Books" />
        <page value="20110101180113" timestamp="2011-01-01T18:01:13Z" ns="0" title="HTML Books" />
        <page value="20110101181007" timestamp="2011-01-01T18:10:07Z" ns="0" title="Quick Tutorial on using Scrapbook to create an HTML Book" />
        <page value="20110101181046" timestamp="2011-01-01T18:10:46Z" ns="0" title="Frequently Asked Questions" />
      </results>
    </querypage>
  </query>
</api>