Trimming its initial gains,Bayer CropScience stock today ended the day higher by 2.54 per cent at Rs 939.90 on the Bombay Stock Exchange. In intra-day trade,the scrip surged by 8.98 per cent to touch a high of Rs 999. The stock settled 2.09 per cent higher at Rs 935.50 on the National Stock Exchange. Meanwhile,after a volatile session,the BSE broader Sensex finished the day at 19,420.39,down by 24.83 points from the previous close.