Recently I've been reading The Scottish Highlanders a personal view by Charles MacKinnon - recommended by a fellow XMarker. There, he states that the number of identifiable highland "clans" at the time just prior to Culloden was between forty and fifty - far different than the "modern" history of clans and tartans after the great tartan revival of 1822. It's fascinating (for me at least) to understand and appreciate the full sweep of history for the highland clan system.