Sigh. Well, one approach then would be something like
<desc>A <mentioned>ꝯ</mentioned> glyph used to
indicate a <mentioned>ꝰ</mentioned> character</desc>
So, not knowing any Latin, let's pretend "consensus" appears with the
glyph for LATIN SMALL LETTER CON both at beginning and end. Then it
> Thanks, Syd. The "con" glyph is used consistently for both "con"
> and "us", but "con" occurs only in word-initial position (49
> occurrences), while "us" (243 occurrences)is only word-final or
> (less commonly) -internal.