MELAMPYRUM, cow-WHEAT; a genus of the angiospermia order, belonging to the didynamia class of plants. There are four species, all of them natives of Britain, and growing spontaneously among corn-fields. They are excellent food for cattle; and Linnaeus tells us, that where they abound the yellowest and best butter is made. Their seeds, when mixed with bread, give it a dusky colour; and, according to some authors, produce a vertigo, and other disorders of the head; but this is denied by Mr Withering, though he allows that they give it a bitter taste.