Shares in Morinaga Milk , the Japanese dairy and food producer, plummeted briefly on the Tokyo Stock Exchange this morning [Thursday] after a frog was discovered in one of its puddings. The pudding had been produced by the Morinaga subsidiary in Niigata Prefecture. Shares in the company fell by ¥22 (US$0.19) to ¥308. A stockbroker commented that the incident reminded investors of the food poisoning crisis that hit