The french word for the cross in typography is "obèle" ; obélisque exists too, but is apparently a bit old-fashionned.
Maybe Goscinny was indeed accustomed to the version more widely used in English.
See :
http://www.apropos-savoir.fr/_pg/search ... ob%C3%A8le
In reply to Invisifan, here are translations of typographical signs in french, in the form that hardly anybody uses :
ampersand "&", = "perluète" or "esperluette" in french
octothorpe "#" = "octothorpe", "croisillon"
"<at>" = 'arrobe' or 'arobase' (from the Arabic ar-robas, meaning... one quarter !).
Look like comics swear-words, all these #<at>& !! ;D