By Steve Gelsi
NEW YORK (MarketWatch) -- Energy stocks fell Monday, as the sector continued moving into the red after two straight weeks of losses. The NYSE Arca Oil Index (XOI 997.57, -1.43, -0.14%) fell 0.4% to 994. The NYSE Arca Natural Gas Index (XNG 513.75, -0.85, -0.17%) dipped 0.3% to 513. The Philadelphia Oil Service Index (OSX 190.49, +0.76, +0.40%) subtracted 0.2% to 189.
