Comment #3 on issue 2823 by [email protected]: Patch: Fixes position of mensural c clef
http://code.google.com/p/lilypond/issues/detail?id=2823
all the c clefs I've seen in manuscripts are closest in shape to LilyPond's Petrucci clefs, far from the mensural ones. in all cases the two brevis-like things are above and below the c line, like after Phil's patch. I'm also quite sure that there's no mistake in naming these clefs c clefs - g clefs are a later invention, I think.
http://en.wikipedia.org/wiki/Mensural_notation for facsimiles google for e.g. Petrus Alamire pictures.
