gonville music font results in different text fonts on Linux and Mac

[Klaus Föhl]

Hello,

I've experimentally changed my lilypond installations from feta to gonville,
and while the music grobs are changed in both cases
I find that on Linux debian squeeze 2.12.3 the text font remains
New Century Schoolbook, while on Mac OS X 2.14.2 the text font is changed
to a sans-serif/grotesk version for the entire document.

Both times I unzipped gonville-r9313.zip on the relevant machine
and renamed (mv) the existing "fonts" to a different name and instead
put (mv or cp -pr) the "lilyfonts" directory / folder as "fonts" in place.

The sections on the fonts look the same in 2.12.3 and 2.14.2 documentation.
Is it down to the different OS (Mac vs Linux) which makes for the difference
in the chosen text font? Is it to do with different fonts installed?
Why does the Mac change to some sans-serif (and which one this is?)
and Linux does not?

Best regards

Klaus

P.S. already used  lilypond -dshow-available-fonts x