* Canadian dollar at C$1.3335, or 74.99 U.S. cents * Bond prices higher across the maturity curve TORONTO, Sept 28 (Reuters) - The Canadian dollar flirted with 11-year lows against its U.S. counterpart on Monday as volatile crude oil prices took a negative turn, at one point falling more than 2 percent on worries over weak global demand. The price of crude, a major Canadian export, has plunged by more than half in the last year, dragging the loonie along some 20 percent in that time. * At 9:56 a.m. EDT (1356 GMT), the Canadian dollar was trading at C$1.3335 to the greenback, or 74.99 U.S. cents, softer than the Bank of Canada's official close of C$1.3316, or 75.10 U.S. cents. * The loonie traded between C$1.3319 and C$1.3379 so far on Monday. Last week, it briefly touched C$1.3417, or 74.53 U.S. cents, its weakest level since June 2004. * Potentially market-moving reports on tap this week include Canadian gross domestic product figures for July, due out on Wednesday, and U.S. labour data for September, on Friday. * U.S. crude prices were down 1.95 percent at $44.81, while Brent crude lost 1.98 percent to $47.64. * Despite the Canadian dollar's weakness against the greenback, the currency was stronger than most of its key counterparts. It is expected to trade between C$1.3315 and C$1.3400 against the U.S. dollar on Monday, according to RBC Capital Markets. * Canadian government bond prices were higher across the maturity curve, with the two-year price up 2 Canadian cents to yield 0.532 percent and the benchmark 10-year rising 43 Canadian cents to yield 1.479 percent. * The Canada-U.S. two-year bond spread was -16.1 basis points, while the 10-year spread was -65.3 basis points. (Reporting by Solarina Ho; Editing by Lisa Von Ahn)