Global stock prices are continuing to fall as fears mount over the U.S. economy and the health of the European banking system. On Thursday, stocks indexes in Britain, France and Germany suffered their biggest daily slide in more than two years. On Wall Street, the Dow fell some 400 points. Meanwhile, the Wall Street Journal is reporting that U.S. federal and state regulators are intensifying their scrutiny of the U.S. arms of Europe’s biggest banks, worrying about spillover from Europe’s debt crisis into the U.S. banking system.