About Jelly Roll Morton--he was regarded as an anachronism in the 40's, and even before then, because his style was the "Storyville" style, which was music from a time long gone by.
Of course, for us, the jazz of the 40s is music from a time long gone by too, so that's not a bad thing--

Here is the Red Hot Jazz page--Jellyroll Morton the music files are at the bottom of the page, and they're great!--