A steep and continuing descent in the energy sector proved the main culprit Tuesday for equities in Canada?s largest market, which fell sharply by the session?s closing bell. The S&P/TSX Composite Index plummeted 1116.44 points to end Tuesday at 15,149.60 The Canadian dollar dropped 0.25 cents to 75.37 cents U.S. Energy stocks took a drubbing Tuesday morning, with Ce**vus swooning 81 cents, or 7.9%, to $9.47, and Encana Corporation falling 46 cents, or 4%, to $11.07.