Jon,
I find the Dolmetsch site on notation at http://www.dolmetsch.com/musictheory2.htm useful for questions like this.

It lists a double whole note as equivalent to a breve. It also has the names of notes in (other) foreign languages.

For me, I was brought up with the English system even as you say it is not descriptive. I can never remember which is a whole note so that I can work out the rest.

I play with someone who lived in America for 10 years and he's totally bi-lingual in musical notation. I can interpret measure instead of bar and even, sometimes, follow chords on top of the music without playing the wrong line.

I've persuaded my ISP to add uk.music.notation but as far as I can see ther are no messages there yet.

Mitch