PAL

Ptolemaeus Arabus et Latinus

_ (the underscore) is the placeholder for exactly one character.
% (the percent sign) is the placeholder for no, one or more than one character.
%% (two percent signs) is the placeholder for no, one or more than one character, but not for blank space (so that a search ends at word boundaries).

At the beginning and at the end, these placeholders are superfluous.

avoir accord avec les apparences ‘agreement with the phenomena’

French

References: PH Morelon: I.1:2, 14:10-11
Translation of:
Arabic: موافقاً فيه لما يظهر لنا [PH Morelon: I.1:2, 15:6]