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>
    <allpages apcontinue="De_Newton,_à_Leibnitz,_à_Laplace,_à_Poincaré." />
  </query-continue>
  <query>
    <allpages>
      <p pageid="4" ns="0" title="BLIK STORMING" />
      <p pageid="185" ns="0" title="Bernard Stiegler : «Même s’ils le voulaient, les Etats n’auraient pas les concepts pour changer»" />
      <p pageid="74" ns="0" title="COMPTOIR II" />
      <p pageid="141" ns="0" title="CREMA" />
      <p pageid="76" ns="0" title="Circonflexion" />
      <p pageid="172" ns="0" title="Citizen science in the Internet era" />
      <p pageid="113" ns="0" title="Colloque sur nous à l&#039;Académie des Sciences" />
      <p pageid="167" ns="0" title="Contributions du S7" />
      <p pageid="132" ns="0" title="Cybernité institutionnelle française" />
      <p pageid="109" ns="0" title="DNSDF" />
    </allpages>
  </query>
</api>