The name of the mushroom in many European languages is thought to be derived from its use as an insecticide when sprinkled in milk . This practice have been recorded from Germanic- and Slavic @-@ speaking parts of Europe , as well as the Vosges region and pockets elsewhere in France , and Romania . Albertus Magnus was the first to record it in his work De vegetabilibus some time before 1256 , commenting vocatur fungus muscarum , eo quod in lacte pulverizatus interficit muscas , " it is called the fly mushroom because it is powdered in milk to kill flies . "