Oil and gas stocks traded mostly lower early Thursday even as crude shrugged shrugged off mostly weak economic data from Europe, the U.S. and China to notch a 2% gain. The Amex Oil Index and the Amex Natural Gas Index both shed less than 1% while the Philadelphia Oil Service Sector Index inched higher. Crude oil for May delivery rose 93 cents, or 1.9%, to $50.16 a barrel in electronic trading on Globex.
