The police investigation to find the driver of a white Jaguar that pinned a woman against the Sheepshead Bay subway entrance is continuing. The woman had been standing beneath the elevated train tracks when the car jumped the curb and backed into her. Her left leg was so badly injured that it was amputated in surgery. The car was found abandoned on East 17th Street, between Avenues X and Y; witnesses say a woman and a stocky bald man fled the car. This is just a terrible, horrible, crazy accident: You're just standing there and this happens.